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Multiplicities of positive and negative pions, kaons and unidentified hadrons from deep-inelastic scattering of muons off a liquid hydrogen target
G. D. Alexeev, M. G. Alexeev, C. Alice, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C. D. R. Azevedo, B. Badelek, J. Barth, R. Beck, J. Beckers, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, W.-C. Chang, C. Chatterjee, et al (150)
Oct 17 2024 hep-ex hep-ph arXiv:2410.12005v1

@misc{2410.12005, author = {G.~D.~Alexeev and M.~G.~Alexeev and C.~Alice and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.~D.~R.~Azevedo and B.~Badelek and J.~Barth and R.~Beck and J.~Beckers and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and S.-U.~Chung and A.~Cicuttin and P.~M.~M.~Correia and M.~L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.~S.~Dasgupta and S.~Dasgupta and F.~Delcarro and I.~Denisenko and O.~Yu.~Denisov and S.~V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dünnweber and R.~R.~Dusaev and D.~Ecker and D.~Eremeev and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~J.~Flöthner and W.~Florian and J.~M.~Friedrich and V.~Frolov and L.G.~Garcia Ordòñez and O.~P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and M.~Grüner and A.~Guskov and P.~Haas and D.~von Harrach and M.~Hoffmann and N.~d'Hose and C.-Y.~Hsieh and S.~Ishimoto and A.~Ivanov and T.~Iwata and V.~Jary and R.~Joosten and E.~Kabuß and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.~V.~Khaustov and F.~Klein and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and A.~Yu.~Korzenev and A.~M.~Kotzinian and O.~M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Kunne and K.~Kurek and R.~P.~Kurjata and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.~E.~Lyubovitskij and A.~Maggiora and N.~Makke and G.~K.~Mallot and A.~Maltsev and A.~Martin and J.~Marzec and J.~Matoušek and T.~Matsuda and C.~Menezes Pires and F.~Metzger and W.~Meyer and Yu.~V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and D.~Miura and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Nagaytsev and D.~Neyret and M.~Niemiec and J.~Nový and W.-D.~Nowak and G.~Nukazuka and A.~G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pešek and D.~V.~Peshekhonov and M.~Pešková and S.~Platchkov and J.~Pochodzalla and V.~A.~Polyakov and C.~Quintans and G.~Reicherz and C.~Riedl and D.~I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.~D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Sinha and D.~Spülbeck and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhay and B.~Valinoti and B.~M.~Veit and J.F.C.A.~Veloso and A.~Vijayakumar and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{M}ultiplicities of positive and negative pions, kaons and unidentified hadrons from deep-inelastic scattering of muons off a liquid hydrogen target}, year = {2024}, eprint = {2410.12005}, note = {arXiv:2410.12005v1} }
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The multiplicities of positive and negative pions, kaons and unidentified hadrons produced in deep-inelastic scattering are measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the fraction of the virtual-photon energy transferred to the final-state hadron $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam of both electric charges and a liquid hydrogen target. These measurements cover the kinematic domain with photon virtuality $Q^2 > 1$ (GeV/$c)^2$, $0.004 < x < 0.4$, $0.1 < y < 0.7$ and $0.2 < z < 0.85$, in accordance with the kinematic domain used in earlier published COMPASS multiplicity measurements with an isoscalar target. The calculation of radiative corrections was improved by using the Monte Carlo generator DJANGOH, which results in up to 12\% larger corrections in the low-$x$ region.
High-statistics measurement of Collins and Sivers asymmetries for transversely polarised deuterons
G. D. Alexeev, M. G. Alexeev, C. Alice, A. Amoroso, V. Andrieux, V. Anosov, S. Asatryan, K. Augsten, W. Augustyniak, C. D. R. Azevedo, B. Badelek, J. Barth, R. Beck, J. Beckers, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, W.-C. Chang, et al (167)
Jan 02 2024 hep-ex hep-ph arXiv:2401.00309v1

@misc{2401.00309, author = {G.~D.~Alexeev and M.~G.~Alexeev and C.~Alice and A.~Amoroso and V.~Andrieux and V.~Anosov and S.~Asatryan and K.~Augsten and W.~Augustyniak and C.~D.~R.~Azevedo and B.~Badelek and J.~Barth and R.~Beck and J.~Beckers and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.~G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.~M.~M.~Correia and M.~L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.~S.~Dasgupta and S.~Dasgupta and F.~Delcarro and I.~Denisenko and O.~Yu.~Denisov and S.~V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dunnweber and R.~R.~Dusaev and D.~Ecker and D.~Eremeev and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~J.~Flothner and W.~Florian and J.~M.~Friedrich and V.~Frolov and L.G.~Garcia Ordonez and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and M.~Gruner and A.~Guskov and P.~Haas and D.~von Harrach and M.~Hoffmann and A.~Hoghmrtsyan and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and V.~Jary and R.~Joosten and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.~V.~Khaustov and T.~Klasek and F.~Klein and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.~F.~Konstantinov and A.~Yu.~Korzenev and A.~M.~Kotzinian and O.~M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and F.~Kunne and K.~Kurek and R.~P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.~E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Maltsev and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and C.~Menezes Pires and F.~Metzger and M.~Meyer and W.~Meyer and Yu.~V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and D.~Miura and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Movsisyan and A.~Nagaytsev and D.~Neyret and M.~Niemiec and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.~G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.~V.~Peshekhonov and M.~Peskova and S.~Platchkov and J.~Pochodzalla and V.~A.~Polyakov and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and D.~I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.~D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and D.~Spulbeck and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and Y.~Takanashi and S.~Tessaro and F.~Tessarotto and A.~Thiel and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhay and B.~Valinoti and B.~M.~Veit and J.F.C.A.~Veloso and B.~Ventura and A.~Vijayakumar and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{H}igh-statistics measurement of {C}ollins and {S}ivers asymmetries for transversely polarised deuterons}, year = {2024}, eprint = {2401.00309}, note = {arXiv:2401.00309v1} }
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New results are presented on a high-statistics measurement of Collins and Sivers asymmetries of charged hadrons produced in deep inelastic scattering of muons on a transversely polarised $^6$LiD target. The data were taken in 2022 with the COMPASS spectrometer using the 160 \gevv muon beam at CERN, balancing the existing data on transversely polarised proton targets. The first results from about two-thirds of the new data have total uncertainties smaller by up to a factor of three compared to the previous deuteron measurements. Using all the COMPASS proton and deuteron results, both the transversity and the Sivers distribution functions of the $u$ and $d$ quark, as well as the tensor charge in the measured $x$-range are extracted. In particular, the accuracy of the $d$ quark results is significantly improved.
Final COMPASS results on the transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan process
G. D. Alexeev, M. G. Alexeev, C. Alice, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C. D. R. Azevedo, B. Badelek, J. Barth, R. Beck, J. Beckers, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, W.-C. Chang, C. Chatterjee, et al (164)
Jan 01 2024 hep-ex hep-ph arXiv:2312.17379v1

@misc{2312.17379, author = {G.~D.~Alexeev and M.~G.~Alexeev and C.~Alice and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.~D.~R.~Azevedo and B.~Badelek and J.~Barth and R.~Beck and J.~Beckers and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.~G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.~M.~M.~Correia and M.~L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.~S.~Dasgupta and S.~Dasgupta and F.~Delcarro and I.~Denisenko and O.~Yu.~Denisov and S.~V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dunnweber and R.~R.~Dusaev and D.~Ecker and D.~Eremeev and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~J.~Flothner and W.~Florian and J.~M.~Friedrich and V.~Frolov and L.G.~Garcia Ordonez and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and M.~Gruner and A.~Guskov and P.~Haas and D.~von Harrach and R.~Heitz and M.~Hoffmann and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and V.~Jary and R.~Joosten and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.~V.~Khaustov and F.~Klein and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.~F.~Konstantinov and A.~Yu.~Korzenev and A.~M.~Kotzinian and O.~M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and F.~Kunne and K.~Kurek and R.~P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.~E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Maltsev and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and C.~Menezes Pires and F.~Metzger and M.~Meyer and W.~Meyer and Yu.~V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and D.~Miura and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Nagaytsev and D.~Neyret and M.~Niemiec and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.~G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.~V.~Peshekhonov and M.~Peskova and S.~Platchkov and J.~Pochodzalla and V.~A.~Polyakov and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and D.~I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.~D.~Samoylenko and A.~Sandacz and S.~Sarkar and T.~Savada and I.~A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and D.~Spulbeck and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhay and B.~Valinoti and B.~M.~Veit and J.F.C.A.~Veloso and B.~Ventura and A.~Vijayakumar and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{F}inal {COMPASS} results on the transverse-spin-dependent azimuthal asymmetries in the pion-induced {D}rell-{Y}an process}, year = {2024}, eprint = {2312.17379}, note = {arXiv:2312.17379v1} }
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The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190 GeV/c $\pi^{-}$ beam impinging on a transversely polarised ammonia target. Combining the data of both years, we present final results on the amplitudes of the five azimuthal modulations in the dimuon production cross section. Three of these transverse-spin-dependent azimuthal asymmetries (TSAs) probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs). The other two are induced by subleading effects. These TSAs provide unique new inputs for the study of the nucleon TMD PDFs and their universality properties. In particular, the Sivers TSA observed in this measurement is consistent with the fundamental QCD prediction of a sign change of naive time-reversal-odd TMD PDFs when comparing the Drell-Yan process with semi-inclusive measurements of deep inelastic scattering. Also, within the context of model predictions, the observed transversity TSA is consistent with the expectation of a sign change for the Boer-Mulders function.
Collins and Sivers transverse-spin asymmetries in inclusive muoproduction of $\rho^0$ mesons
G. D. Alexeev, M. G. Alexeev, C. Alice, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C. D. R. Azevedo, B. Badelek, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, V. E. Burtsev, W.-C. Chang, C. Chatterjee, et al (172)
Nov 02 2022 hep-ex hep-ph arXiv:2211.00093v2

@misc{2211.00093, author = {G.~D.~Alexeev and M.~G.~Alexeev and C.~Alice and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.~D.~R.~Azevedo and B.~Badelek and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.~E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.~G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.~M.~M.~Correia and M.~L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.~S.~Dasgupta and S.~Dasgupta and F.~Del Carro and I.~Denisenko and O.~Yu.~Denisov and S.~V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dünnweber and R.~R.~Dusaev and D.~Ecker and A.~Efremov and C.~Elia and D.~Eremeev and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~J.~Flöthner and W.~Florian and J.~M.~Friedrich and V.~Frolov and L.G.~Garcia Ordòñez and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and M.~Grüner and A.~Guskov and D.~von Harrach and M.~Hoffmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and V.~Jary and R.~Joosten and E.~Kabuß and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.~V.~Khaustov and F.~Klein and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.~F.~Konstantinov and A.~M.~Korzenev and A.~M.~Kotzinian and O.~M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and F.~Kunne and K.~Kurek and R.~P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.~E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.~K.~Mallot and A.~Maltsev and S.~A.~Mamon and A.~Martin and J.~Marzec and J.~Matoušek and T.~Matsuda and G.~Mattson and C.~Menezes Pires and F.~Metzger and M.~Meyer and W.~Meyer and Yu.~V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and D.~Miura and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Nový and W.-D.~Nowak and G.~Nukazuka and A.~G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pešek and D.~V.~Peshekhonov and M.~Pešková and S.~Platchkov and J.~Pochodzalla and V.~A.~Polyakov and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.~I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.~D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and M.~Slunecka and F.~Sozzi and D.~Spülbeck and A.~Srnka and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhay and B.~Valinoti and B.~M.~Veit and J.F.C.A.~Veloso and B.~Ventura and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{C}ollins and {S}ivers transverse-spin asymmetries in inclusive muoproduction of $\rho^0$ mesons}, year = {2022}, eprint = {2211.00093}, note = {arXiv:2211.00093v2} }
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The production of vector mesons in deep inelastic scattering is an interesting yet scarsely explored channel to study the transverse spin structure of the nucleon and the related phenomena. The COMPASS collaboration has performed the first measurement of the Collins and Sivers asymmetries for inclusively produced $\rho^0$ mesons. The analysis is based on the data set collected in deep inelastic scattering in $2010$ using a $160\,\,\rm{GeV}/c$ $\mu^+$ beam impinging on a transversely polarized $\rm{NH}_3$ target. The $\rho^{0}$ mesons are selected from oppositely charged hadron pairs, and the asymmetries are extracted as a function of the Bjorken-$x$ variable, the transverse momentum of the pair and the fraction of the energy $z$ carried by the pair. Indications for positive Collins and Sivers asymmetries are observed.
Spin Density Matrix Elements in Exclusive $\rho ^0$ Meson Muoproduction
G. D. Alexeev, M. G. Alexeev, C. Alice, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C. D. R. Azevedo, B. Badelek, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, V. E. Burtsev, W.-C. Chang, C. Chatterjee, et al (170)
Nov 01 2022 hep-ex hep-ph arXiv:2210.16932v2

@misc{2210.16932, author = {G.~D.~Alexeev and M.~G.~Alexeev and C.~Alice and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.~D.~R.~Azevedo and B.~Badelek and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.~E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.~G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.~M.~M.~Correia and M.~L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.~S.~Dasgupta and S.~Dasgupta and F.~Del Carro and I.~Denisenko and O.~Yu.~Denisov and S.~V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dünnweber and R.~R.~Dusaev and D.~Ecker and A.~Efremov and D.~Eremeev and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~J.~Flöthner and W.~Florian and J.~M.~Friedrich and V.~Frolov and L.G.~Garcia Ordòñez and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and M.~Grüner and A.~Guskov and D.~von Harrach and M.~Hoffmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and V.~Jary and R.~Joosten and E.~Kabuß and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.~V.~Khaustov and F.~Klein and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.~F.~Konstantinov and A.~M.~Korzenev and A.~M.~Kotzinian and O.~M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and F.~Kunne and K.~Kurek and R.~P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.~E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.~K.~Mallot and A.~Maltsev and S.~A.~Mamon and A.~Martin and J.~Marzec and J.~Matoušek and T.~Matsuda and G.~Mattson and C.~Menezes Pires and F.~Metzger and M.~Meyer and W.~Meyer and Yu.~V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and D.~Miura and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and M.~Niemiec and J.~Nový and W.-D.~Nowak and G.~Nukazuka and A.~G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pešek and D.~V.~Peshekhonov and M.~Pešková and S.~Platchkov and J.~Pochodzalla and V.~A.~Polyakov and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and D.~I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.~D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and M.~Slunecka and D.~Spülbeck and A.~Srnka and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhay and B.~Valinoti and B.~M.~Veit and J.F.C.A.~Veloso and B.~Ventura and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{S}pin {D}ensity {M}atrix {E}lements in {E}xclusive $\rho ^0$ {M}eson {M}uoproduction}, year = {2022}, eprint = {2210.16932}, note = {arXiv:2210.16932v2} }
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We report on a measurement of Spin Density Matrix Elements (SDMEs) in hard exclusive $\rho ^0$ meson muoproduction at COMPASS using 160~GeV/$c$ polarised $ \mu ^{+}$ and $ \mu ^{-}$ beams impinging on a liquid hydrogen target. The measurement covers the kinematic range 5.0~GeV/$c^2$ $< W <$ 17.0~GeV/$c^2$, 1.0 (GeV/$c$)$^2$ $< Q^2 <$ 10.0 (GeV/$c$)$^2$ and 0.01 (GeV/$c$)$^2$ $< p_{\rm{T}}^2 <$ 0.5 (GeV/$c$)$^2$. Here, $W$ denotes the mass of the final hadronic system, $Q^2$ the virtuality of the exchanged photon, and $p_{\rm{T}}$ the transverse momentum of the $\rho ^0$ meson with respect to the virtual-photon direction. The measured non-zero SDMEs for the transitions of transversely polarised virtual photons to longitudinally polarised vector mesons ($\gamma^*_T \to V^{ }_L$) indicate a violation of $s$-channel helicity conservation. Additionally, we observe a dominant contribution of natural-parity-exchange transitions and a very small contribution of unnatural-parity-exchange transitions, which is compatible with zero within experimental uncertainties. The results provide important input for modelling Generalised Parton Distributions (GPDs). In particular, they may allow one to evaluate in a model-dependent way the role of parton helicity-flip GPDs in exclusive $\rho ^0$ production.
Double $J/\psi$ production in pion-nucleon scattering at COMPASS
G.D. Alexeev, M.G. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, V.E. Burtsev, W.-C. Chang, C. Chatterjee, et al (175)
Apr 06 2022 hep-ex hep-ph arXiv:2204.01817v1

@misc{2204.01817, author = {G.D.~Alexeev and M.G.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and D.~Eremeev and P.D.~Eversheim and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~Floethner and W Florian and C.~Franco and J.M.~Friedrich and V.~Frolov and L.G.~Garcia Ordonez and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and M.~Gorzellik and A.~Grasso and A.~Gridin and S.~Groote and M.~Grosse Perdekamp and B.~Grube and M.~Gruener and A.~Guskov and D.~von Harrach and M.~Hoffmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and A.~Khatun and G.V.~Khaustov and Yu.A.~Khokhlov and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.F.~Konstantinov and A.~Korzenev and S.~Koshkarev and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and C.~Menezes Pires and F.~Metzger and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and Y.~Miyachi and R.~Molina and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rychter and A.~Rymbekova and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and S.~Schmeing and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and M.~Slunecka and D.~Spuelbeck and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and T.~Triloki and V.~Tskhaty and B.~Valinoti and B.M.~Veit and J.~F.~C.~A.~Veloso and B.~Ventura and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and M.~Ziembicki}, title = {{D}ouble ${J}/\psi$ production in pion-nucleon scattering at {COMPASS}}, year = {2022}, eprint = {2204.01817}, note = {arXiv:2204.01817v1} }
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We present the study of the production of double $J/\psi$ mesons using COMPASS data collected with a 190 GeV/$c$ $\pi^-$ beam scattering off NH$_{3}$, Al and W targets. Kinematic distributions of the collected double $J/\psi$ events are analysed, and the double $J/\psi$ production cross section is estimated for each of the COMPASS targets. The results are compared to predictions from single- and double-parton scattering models as well as the pion intrinsic charm and the tetraquark exotic resonance hypotheses. It is demonstrated that the single parton scattering production mechanism gives the dominant contribution that is sufficient to describe the data. An upper limit on the double intrinsic charm content of pion is evaluated. No significant signatures that could be associated with exotic tetraquarks are found in the double $J/\psi$ mass spectrum.
The exotic meson $\pi_1(1600)$ with $J^{PC} = 1^{-+}$ and its decay into $\rho(770)\pi$
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, V.E. Burtsev, et al (176)
Aug 05 2021 hep-ex hep-ph arXiv:2108.01744v2

@misc{2108.01744, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and D.~Eremeev and P.D.~Eversheim and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and K.~Floethner and C.~Franco and J.M.~Friedrich and V.~Frolov and L.G.~Garcia Ordonez and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and D.~Giordano and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and F.~Haas and D.~von Harrach and M.~Hoffmann and R.~Heitz and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and F.~Metzger and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.G.~Olshevsky and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rymbekova and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and S.~Schmeing and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and M.~Slunecka and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and T.~Triloki and S.~Uhl and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{T}he exotic meson $\pi_1(1600)$ with ${J}^{{PC}} = 1^{-+}$ and its decay into $\rho(770)\pi$}, year = {2021}, eprint = {2108.01744}, howpublished = {Phys.Rev.D 105 (2022) 1, 012005}, doi = {10.1103/PhysRevD.105.012005}, note = {arXiv:2108.01744v2} }
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We study the spin-exotic $J^{PC} = 1^{-+}$ amplitude in single-diffractive dissociation of 190 GeV$/c$ pions into $\pi^-\pi^-\pi^+$ using a hydrogen target and confirm the $\pi_1(1600) \to \rho(770) \pi$ amplitude, which interferes with a nonresonant $1^{-+}$ amplitude. We demonstrate that conflicting conclusions from previous studies on these amplitudes can be attributed to different analysis models and different treatment of the dependence of the amplitudes on the squared four-momentum transfer and we thus reconcile their experimental findings. We study the nonresonant contributions to the $\pi^-\pi^-\pi^+$ final state using pseudo-data generated on the basis of a Deck model. Subjecting pseudo-data and real data to the same partial-wave analysis, we find good agreement concerning the spectral shape and its dependence on the squared four-momentum transfer for the $J^{PC} = 1^{-+}$ amplitude and also for amplitudes with other $J^{PC}$ quantum numbers. We investigate for the first time the amplitude of the $\pi^-\pi^+$ subsystem with $J^{PC} = 1^{--}$ in the $3\pi$ amplitude with $J^{PC} = 1^{-+}$ employing the novel freed-isobar analysis scheme. We reveal this $\pi^-\pi^+$ amplitude to be dominated by the $\rho(770)$ for both the $\pi_1(1600)$ and the nonresonant contribution. We determine the $\rho(770)$ resonance parameters within the three-pion final state. These findings largely confirm the underlying assumptions for the isobar model used in all previous partial-wave analyses addressing the $J^{PC} = 1^{-+}$ amplitude.
Probing transversity by measuring $\Lambda$ polarisation in SIDIS
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, V.E. Burtsev, et al (180)
Apr 29 2021 hep-ex arXiv:2104.13585v2

@misc{2104.13585, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and P.~Faccioli and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and L.G.~Garcia Ordonez and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and D.~Giordano and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~von Harrach and R.~Heitz and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and E.~Kabuss and D.H.~Kang and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and T.S.~Negrini and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rymbekova and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and H.~Schmieden and A.~Selyunin and K.~Sharko and L.~Sinha and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and S.~Uhl and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and P.~Zavada and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{P}robing transversity by measuring $\{L}ambda$ polarisation in {SIDIS}}, year = {2021}, eprint = {2104.13585}, note = {arXiv:2104.13585v2} }
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Based on the observation of sizeable target-transverse-spin asymmetries in single-hadron and hadron-pair production in Semi-Inclusive measurements of Deep Inelastic Scattering (SIDIS), the chiral-odd transversity quark distribution functions $h_1^q$ are nowadays well established. Several possible channels to access these functions were originally proposed. One candidate is the measurement of the polarisation of $\Lambda$ hyperons produced in SIDIS off transversely polarised nucleons, where the transverse polarisation of the struck quark might be transferred to the final-state hyperon. In this article, we present the COMPASS results on the transversity-induced polarisation of $\Lambda$ and $\bar{\Lambda}$ hyperons produced in SIDIS off transversely polarised protons. Within the experimental uncertainties, no significant deviation from zero was observed. The results are discussed in the context of different models taking into account previous experimental results on $h_1^u$ and $h_1^d$.
Spin Density Matrix Elements in Exclusive $\omega$ Meson Muoproduction $^*$
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, et al (181)
Sep 08 2020 hep-ex arXiv:2009.03271v3

@misc{2009.03271, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and P.~Faccioli and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo Horikawa and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and C.~Regali and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Sinha and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and T.~Szameitat and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and P.~Zavada and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{S}pin {D}ensity {M}atrix {E}lements in {E}xclusive $\omega$ {M}eson {M}uoproduction $^*$}, year = {2020}, eprint = {2009.03271}, note = {arXiv:2009.03271v3} }
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We report on a measurement of Spin Density Matrix Elements (SDMEs) in hard exclusive $\omega$ meson muoproduction on the proton at COMPASS using 160 GeV/$c$ polarised $ \mu ^{+}$ and $ \mu ^{-}$ beams impinging on a liquid hydrogen target. The measurement covers the range 5.0 GeV/$c^2$ $< W <$ 17.0 GeV/$c^2$, with the average kinematics $\langle Q^{2} \rangle=$ 2.1 (GeV/$c$)$^2$, $\langle W \rangle= 7.6$ GeV/$c^2$, and $\langle p^{2}_{\rm T} \rangle = 0.16$ (GeV/$c$)$^2$. Here, $Q^2$ denotes the virtuality of the exchanged photon, $W$ the mass of the final hadronic system and $p_T$ the transverse momentum of the $\omega$ meson with respect to the virtual-photon direction. The measured non-zero SDMEs for the transitions of transversely polarised virtual photons to longitudinally polarised vector mesons ($\gamma^*_T \to V_L$) indicate a violation of $s$-channel helicity conservation. Additionally, we observe a sizeable contribution of unnatural-parity-exchange (UPE) transitions that decreases with increasing $W$. The results provide important input for modelling Generalised Parton Distributions (GPDs). In particular, they may allow to evaluate in a model-dependent way the contribution of UPE transitions and assess the role of parton helicity-flip GPDs in exclusive $\omega$ production.
Triangle Singularity as the Origin of the $a_1(1420)$
G.D. Alexeev, M.G. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, et al (178)
Jun 11 2020 hep-ph hep-ex arXiv:2006.05342v3

@misc{2006.05342, author = {G.D.~Alexeev and M.G.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Sinha and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and P.~Zavada and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{T}riangle {S}ingularity as the {O}rigin of the $a_1(1420)$}, year = {2020}, eprint = {2006.05342}, howpublished = {Phys. Rev. Lett. 127, 082501 (2021)}, doi = {10.1103/PhysRevLett.127.082501}, note = {arXiv:2006.05342v3} }
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The COMPASS experiment recently discovered a new isovector resonance-like signal with axial-vector quantum numbers, the $a_1(1420)$, decaying to $f_0(980)\pi$. With a mass too close to and a width smaller than the axial-vector ground state $a_1(1260)$, it was immediately interpreted as a new light exotic meson, similar to the $X$, $Y$, $Z$ states in the hidden-charm sector. We show that a resonance-like signal fully matching the experimental data is produced by the decay of the $a_1(1260)$ resonance into $K^\ast(\to K\pi)\bar{K}$ and subsequent rescattering through a triangle singularity into the coupled $f_0(980)\pi$ channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having less parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonance-like structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.
Antiproton over proton and K$^-$ over K$^+$ multiplicity ratios at high $z$ in DIS
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, F. Bradamante, A. Bressan, et al (179)
Mar 27 2020 hep-ex arXiv:2003.11791v1

@misc{2003.11791, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and P.~Faccioli and M.~Faessler and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and G.~Reicherz and C.~Riedl and T.~Rudnicki and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Sinha and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and K.~Zaremba and P.~Zavada and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{A}ntiproton over proton and {K}$^-$ over {K}$^+$ multiplicity ratios at high $z$ in {DIS}}, year = {2020}, eprint = {2003.11791}, note = {arXiv:2003.11791v1} }
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The $\bar{\rm p} $ over p multiplicity ratio is measured in deep-inelastic scattering for the first time using (anti-) protons carrying a large fraction of the virtual-photon energy, $z>0.5$. The data were obtained by the COMPASS Collaboration using a 160 GeV muon beam impinging on an isoscalar $^6$LiD target. The regime of deep-inelastic scattering is ensured by requiring $Q^2$ > 1 (GeV/$c$)$^2$ for the photon virtuality and $W > 5$ GeV/$c^2$ for the invariant mass of the produced hadronic system. The range in Bjorken-$x$ is restricted to $0.01 < x < 0.40$. Protons and antiprotons are identified in the momentum range $20 \div 60$ GeV/$c$. In the whole studied $z$-region, the $\bar{\rm p}$ over p multiplicity ratio is found to be below the lower limit expected from calculations based on leading-order perturbative Quantum Chromodynamics (pQCD). Extending our earlier analysis of the K$^-$ over K$^+$ multiplicity ratio by including now events with larger virtual-photon energies, this ratio becomes closer to the expectation of next-to-leading order pQCD. The results of both analyses strengthen our earlier conclusion that the phase space available for hadronisation should be taken into account in the pQCD formalism.
Contribution of exclusive diffractive processes to the measured azimuthal asymmetries in SIDIS
J. Agarwala, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Berenguer Antequera, J. Bernhard, M. Bodlak, et al (187)
Dec 24 2019 hep-ex arXiv:1912.10322v1

@misc{1912.10322, author = {J.~Agarwala and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Berenguer Antequera and J.~Bernhard and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.M.M.~Correia and M.L.~Crespo and D.~D'Ago and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and I.~Denisenko and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and K.~Lavickova and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.~Naim and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and H.~Pekeler and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and C.~Riedl and D.I.~Ryabchikov and T.~Rudnicki and A.~Rybnikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Sinha and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and A.~Townsend and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and B.~Ventura and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and M.~Wilfert and K.~Zaremba and P.~Zavada and M.~Zavertyaev and M.~Zemko and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{C}ontribution of exclusive diffractive processes to the measured azimuthal asymmetries in {SIDIS}}, year = {2019}, eprint = {1912.10322}, note = {arXiv:1912.10322v1} }
PDF
Hadron leptoproduction in Semi-Inclusive measurements of Deep-Inelastic Scattering (SIDIS) on unpolarised nucleons allows one to get information on the intrinsic transverse momentum of quarks in a nucleon and on the Boer-Mulders function through the measurement of azimuthal modulations in the cross section. These modulations were recently measured by the HERMES experiment at DESY on proton and deuteron targets, and by the COMPASS experiment using the CERN SPS muon beam and a $^6$LiD target. In both cases, the amplitudes of the $\cos\phi_h$ and $\cos 2\phi_h$ modulations show strong kinematic dependences for both positive and negative hadrons. It has been known since some time that the measured final-state hadrons in those SIDIS experiments receive a contribution from exclusive diffractive production of vector mesons, particularly important at large values of $z$, the fraction of the virtual photon energy carried by the hadron. In previous measurements of azimuthal asymmetries this contribution was not taken into account, because it was not known that it could distort the azimuthal modulations. Presently, a method to evaluate the contribution of the exclusive reactions to the azimuthal asymmetries measured by COMPASS has been developed. The subtraction of this contribution results in a better understanding of the kinematic effects, and the remaining non-zero $\cos 2\phi_h$ modulation gives indication for a non-zero Boer-Mulders effect.
Measurement of the cross section for hard exclusive $\pi^0$ leptoproduction
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, M. Bodlak, P. Bordalo, F. Bradamante, et al (183)
Mar 29 2019 hep-ex arXiv:1903.12030v1

@misc{1903.12030, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and P.-J.~Lin and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and C.~Naim and A.~Nagaytsev and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and A.~Selyunin and L.~Silva and L.~Sinha and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and M.~Wilfert and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and Y.~Zhao and M.~Ziembicki}, title = {{M}easurement of the cross section for hard exclusive $\pi^0$ leptoproduction}, year = {2019}, eprint = {1903.12030}, note = {arXiv:1903.12030v1} }
PDF
We report on a measurement of hard exclusive $\pi^0$ muoproduction on the proton by COMPASS using 160 GeV/$c$ polarised $\mu^+$ and $\mu^-$ beams of the CERN SPS impinging on a liquid hydrogen target. From the average of the measured $\mu^+$ and $\mu^-$ cross sections, the virtual-photon proton cross section is determined as a function of the squared four-momentum transfer between initial and final proton in the range $0.08\,(\text{GeV/}c)^2 < |t| < 0.64\,(\text{GeV/}c)^2$. The average kinematics of the measurement are $\langle Q^2 \rangle =2.0\; {(\text{GeV}/c)^2}$, $\langle \nu \rangle = 12.8\; {\text{GeV}}$, $\langle x_{Bj} \rangle = 0.093 $ and $\langle -t \rangle = 0.256\; {(\text{GeV}/c)^2} $. Fitting the azimuthal dependence reveals a combined contribution by transversely and longitudinally polarised photons of $(8.1 \ \pm \ 0.9_{\text{stat}}{}_{- \ 1.0}^{+ \ 1.1}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$, as well as transverse-transverse and longitudinal-transverse interference contributions of $(-6.0 \pm 1.3_{\text{stat}}{}_{- \ 0.7}^{+ \ 0.7}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$ and $(1.4 \pm 0.5_{\text{stat}}{}_{- \ 0.2}^{+ \ 0.3}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$, respectively. Our results provide important input for modelling Generalised Parton Distributions. In the context of the phenomenological Goloskokov-Kroll model, the statistically significant transverse-transverse interference contribution constitutes clear experimental evidence for the chiral-odd GPD $\overline{E}_T$.
Measurement of $P_T$-weighted Sivers asymmetries in leptoproduction of hadrons
M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, V. Barone, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, et al (193)
Sep 11 2018 hep-ex arXiv:1809.02936v1

@misc{1809.02936, author = {M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and V.~Barone and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and A.A.~Lednev and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and H.~Schmieden and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and M.~Wilfert and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki}, title = {{M}easurement of ${P}_{T}$-weighted {S}ivers asymmetries in leptoproduction of hadrons}, year = {2018}, eprint = {1809.02936}, note = {arXiv:1809.02936v1} }
PDF
The transverse spin asymmetries measured in semi-inclusive leptoproduction of hadrons, when weighted with the hadron transverse momentum $P_T$, allow for the extraction of important transverse-momentum-dependent distribution functions. In particular, the weighted Sivers asymmetries provide direct information on the Sivers function, which is a leading-twist distribution that arises from a correlation between the transverse momentum of an unpolarised quark in a transversely polarised nucleon and the spin of the nucleon. Using the high-statistics data collected by the COMPASS Collaboration in 2010 with a transversely polarised proton target, we have evaluated two types of $P_T$-weighted Sivers asymmetries, which are both proportional to the product of the firsttransverse moment of the Sivers function and of the fragmentation function. The results are compared to the standard unweighted Sivers asymmetries and used to extract the first transverse moments of the Sivers distributions for $u$ and $d$ quarks.
Letter of Intent: A New QCD facility at the M2 beam line of the CERN SPS (COMPASS++/AMBER)
B. Adams, C.A. Aidala, R.Akhunzyanov, G.D. Alexeev, M.G. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, A. Azhibekov, B. Badelek, F. Balestra, M. Ball, J. Barth, R.Beck, Y. Bedfer, et al (247)
Aug 03 2018 hep-ex physics.ins-det arXiv:1808.00848v6

@misc{1808.00848, author = {B.~Adams and C.A.~Aidala and R.Akhunzyanov and G.D.~Alexeev and M.G.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and A.~Azhibekov and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.Beck and Y.~Bedfer and J.~Berenguer Antequera and J.C.~Bernauer and J.Bernhard and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buchele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and X.~Chen and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and P.~Correia and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and N.~Dashyan and I.~Denisenko and O.Yu.~Denisov and L.~Dhara and N.~d'Hose and F.~Donato and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Dunnweber and R.R.~Dusaev and M.~Dziewiecki and A.~Dzyuba and A.~Efremov and P.~Egelhof and A.~Elagin and P.D.~Eversheim and M.~Faessler and J.~Fedotova and A.~Ferrero and M.~Finger and M.~Finger Jr.~and H.~Fischer and C.~Franco and J.M.~Friedrich and V.~Frolov and A.~Futch and F.Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and S.~Gevorkyan and Y.~Ghandilyan and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and R.I.~Gushterski and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and X.~He and R.~Heitz and F.~Herrmann and N.~Horikawa and C.-Y.~Hsieh and S.~Huber and A.~Inglessi and A.~Ilyichev and T.~Isataev and S.~Ishimoto and A.~Ivanov and N.~Ivanov and Yu.~Ivanshin and T.~Iwata and M.~Jandek and V.~Jary and C.-M.~Jen and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and A.~Kabyshev and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and M.~Kim and O.~Kiselev and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and A.~Koval and Z.~Kral and M.~Kraemer and F.~Krinner and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and K.~Kuterbekov and I.I.~Kuznetsov and A.~Kveton and E.A.~Levchenko and S.~Levorato and Y.-S.~Lian and Y.~Liang and J.~Lichtenstadt and P.-J.~Lin and K.~Liu and M.X.~Liu and R.~Longo and W.~Lorenzon and M.~Losekamm and V.E.~Lyubovitskij and E.~Maev and A.~Maggiora and A.~Magnon and V.~Makarenko and N.~Makins and N.~Makke and G.K.~Mallot and A.~Maltsev and S.A.~Mamon and B.~Marianski and A.~Martin and H.~Marukyan and J.~Marzec and N.~Masi and J.~Matousek and H.~Matsuda and G.~Mattson and G.V.~Meshcheryakov and W.~Meyer and M.~Meyer and Yu.V.Mikhailov and M.~Mikhasenko and M.~Minot and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and C.Naim and D.~Neyret and G.~Nigmatkulov and A.~Mkrtchyan and H.~Mkrtchyan and J.~Novy and W.-D.~Nowak and F.~Nozzoli and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and J.D.~Osborn and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and D.V.~Peshekhonov and M.~Pesek and M.~Peskova and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and T.~Poeschl and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and R.~Raymond and G.~Reicherz and C.~Riedl and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and M.~Sarsour and I.A.~Savin and G.~Sbrizzai and H.~Schmieden and E.~Seder and A.~Selyunin and H.~Simon and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and P.~Sznajder and M.~Tasevsky and V.~Tchekhovski and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vassiliev and A.~Vauth and B.M.~Veit and B.~Ventura and J.~Veloso and A.~Vidon and M.~Virius and A.~Vorobyev and M.~Wagner and S.~Wallner and M.~Wilfert and Z.~Xiao and N.~Xu and J.~Yang and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and H.~Zhao and Y.~Zhao and N.~Zhuravlev and M.~Ziembicki and P.~Zuccon}, title = {{L}etter of {I}ntent: {A} {N}ew {QCD} facility at the {M}2 beam line of the {CERN} {SPS} ({COMPASS}++/{AMBER})}, year = {2018}, eprint = {1808.00848}, note = {arXiv:1808.00848v6} }
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A New QCD facility at the M2 beam line of the CERN SPS COMPASS++/AMBER
Light isovector resonances in $\pi^- p \to \pi^-\pi^-\pi^+ p$ at 190 GeV/${\it c}$
M. Aghasyan, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, et al (205)
Feb 19 2018 hep-ex hep-ph arXiv:1802.05913v2

@misc{1802.05913, author = {M.~Aghasyan and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Hass and D.~Hahne and G.~Hamar and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.~S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and T.~Schluter and S.~Schmeing and H.~Schmieden and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki}, title = {{L}ight isovector resonances in $\pi^- p \to \pi^-\pi^-\pi^+ p$ at 190 {G}e{V}/${\it c}$}, year = {2018}, eprint = {1802.05913}, note = {arXiv:1802.05913v2} }
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We have performed the most comprehensive resonance-model fit of $\pi^-\pi^-\pi^+$ states using the results of our previously published partial-wave analysis (PWA) of a large data set of diffractive-dissociation events from the reaction $\pi^- + p \to \pi^-\pi^-\pi^+ + p_\text{recoil}$ with a 190 GeV/$c$ pion beam. The PWA results, which were obtained in 100 bins of three-pion mass, $0.5 < m_{3\pi} < 2.5$ GeV/$c^2$, and simultaneously in 11 bins of the reduced four-momentum transfer squared, $0.1 < t' < 1.0$ $($GeV$/c)^2$, are subjected to a resonance-model fit using Breit-Wigner amplitudes to simultaneously describe a subset of 14 selected waves using 11 isovector light-meson states with $J^{PC} = 0^{-+}$, $1^{++}$, $2^{++}$, $2^{-+}$, $4^{++}$, and spin-exotic $1^{-+}$ quantum numbers. The model contains the well-known resonances $\pi(1800)$, $a_1(1260)$, $a_2(1320)$, $\pi_2(1670)$, $\pi_2(1880)$, and $a_4(2040)$. In addition, it includes the disputed $\pi_1(1600)$, the excited states $a_1(1640)$, $a_2(1700)$, and $\pi_2(2005)$, as well as the resonancelike $a_1(1420)$. We measure the resonance parameters mass and width of these objects by combining the information from the PWA results obtained in the 11 $t'$ bins. We extract the relative branching fractions of the $\rho(770) \pi$ and $f_2(1270) \pi$ decays of $a_2(1320)$ and $a_4(2040)$, where the former one is measured for the first time. In a novel approach, we extract the $t'$ dependence of the intensity of the resonances and of their phases. The $t'$ dependence of the intensities of most resonances differs distinctly from the $t'$ dependence of the nonresonant components. For the first time, we determine the $t'$ dependence of the phases of the production amplitudes and confirm that the production mechanism of the Pomeron exchange is common to all resonances.
Transverse Extension of Partons in the Proton probed by Deeply Virtual Compton Scattering
R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, et al (207)
Feb 09 2018 hep-ex nucl-ex arXiv:1802.02739v2

@misc{1802.02739, author = {R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and E.~Burtin and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and G.~Pesaro and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.~S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and H.~Schmieden and K.~Schoennig and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.~M.~Veit and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{T}ransverse {E}xtension of {P}artons in the {P}roton probed by {D}eeply {V}irtual {C}ompton {S}cattering}, year = {2018}, eprint = {1802.02739}, doi = {10.1016/j.physletb.2019.04.038}, note = {arXiv:1802.02739v2} }
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We report on the first measurement of exclusive single-photon muoproduction on the proton by COMPASS using 160 GeV/$c$ polarized $\mu^+$ and $\mu^-$ beams of the CERN SPS impinging on a liquid hydrogen target. We determine the dependence of the average of the measured $\mu^+$ and $\mu^-$ cross sections for deeply virtual Compton scattering on the squared four-momentum transfer $t$ from the initial to the final final proton. The slope $B$ of the $t$-dependence is fitted with a single exponential function, which yields $B=(4.3 \ \pm \ 0.6_{\text{stat}}\_{- \ 0.3}^{+ \ 0.1}\big\rvert_{\text{sys}}) (\text{GeV}/c)^{-2}$. This result can be converted into an average transverse extension of partons in the proton, $\sqrt{\langle r_{\perp}^2 \rangle} = (0.58 \ \pm \ 0.04_{\text{stat}}\_{- \ 0.02}^{+ \ 0.01}\big\rvert_{\text{sys}})\text{fm}$. For this measurement, the average virtuality of the photon mediating the interaction is $\langle Q^2 \rangle = 1.8\,(\text{GeV/}c)^2$ and the average value of the Bjorken variable is $\langle x_{\text{Bj}} \rangle = 0.056$.
K$^{-}$ over K$^{+}$ multiplicity ratio for kaons produced in DIS with a large fraction of the virtual-photon energy
R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, et al (191)
Feb 05 2018 hep-ex hep-ph arXiv:1802.00584v2

@misc{1802.00584, author = {R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and T.~Iwata and M.~Jandek and T.~Jary and R.~Joosten and P.~Joerg and K.~Juraskova and E.~Kabuss and F.~Kaspar and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and A.A.~Lednev and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevskiy and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and H.~Schmieden and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and B.M.~Veit and J.~Veloso and A.Vidon and M.~Virius and M.~Wagner and S.~Wallner and M.~Wilfert and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki}, title = {{K}$^{-}$ over {K}$^{+}$ multiplicity ratio for kaons produced in {DIS} with a large fraction of the virtual-photon energy}, year = {2018}, eprint = {1802.00584}, note = {arXiv:1802.00584v2} }
PDF
The K$^{-}$ over K$^{+}$ multiplicity ratio is measured in deep-inelastic scattering, for the first time for kaons carrying a large fraction $z$ of the virtual-photon energy. The data were obtained by the COMPASS collaboration using a 160 GeV muon beam and an isoscalar $^6$LiD target. The regime of deep-inelastic scattering is ensured by requiring $Q^2>1$ (GeV/$c)^2$ for the photon virtuality and $W>5$ GeV/$c^2$ for the invariant mass of the produced hadronic system. Kaons are identified in the momentum range from 12 GeV/$c$ to 40 GeV/$c$, thereby restricting the range in Bjorken-$x$ to $0.01<x<0.40$. The $z$-dependence of the multiplicity ratio is studied for $z>0.75$. For very large values of $z$, $i.e.$ $z>0.8$, we observe the kaon multiplicity ratio to fall below the lower limits expected from calculations based on leading and next-to-leading order perturbative quantum chromodynamics. Also, the kaon multiplicity ratio shows a strong dependence on the missing mass of the single-kaon production process. This suggests that within the perturbative quantum chromodynamics formalism an additional correction may be required, which takes into account the phase space available for hadronisation.
Longitudinal double-spin asymmetry $A_1^{\rm p}$ and spin-dependent structure function $g_1^{\rm p}$ of the proton at small values of $x$ and $Q^2$
M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (209)
Oct 04 2017 hep-ex arXiv:1710.01014v1

@misc{1710.01014, author = {M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{L}ongitudinal double-spin asymmetry ${A}_1^{\rm p}$ and spin-dependent structure function $g_1^{\rm p}$ of the proton at small values of $x$ and ${Q}^2$}, year = {2017}, eprint = {1710.01014}, note = {arXiv:1710.01014v1} }
PDF
We present a precise measurement of the proton longitudinal double-spin asymmetry $A_1^{\rm p}$ and the proton spin-dependent structure function $g_1^{\rm p}$ at photon virtualities $0.006~({\rm GeV}/c)^2<Q^2 < 1~({\rm GeV}/c)^2$ in the Bjorken $x$ range of $4 \times 10^{-5} < x < 4 \times 10^{-2}$. The results are based on data collected by the COMPASS Collaboration at CERN using muon beam energies of $160~{\rm GeV}$ and $200~{\rm GeV}$. The statistical precision is more than tenfold better than that of the previous measurement in this region. In the whole range of $x$, the measured values of $A_1^{\rm p}$ and $g_1^{\rm p}$ are found to be positive. It is for the first time that spin effects are found at such low values of $x$.
Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering
M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (211)
Sep 22 2017 hep-ex nucl-ex arXiv:1709.07374v1

@misc{1709.07374, author = {M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and L.~Capozza and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Moretti and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{T}ransverse-momentum-dependent {M}ultiplicities of {C}harged {H}adrons in {M}uon-{D}euteron {D}eep {I}nelastic {S}cattering}, year = {2017}, eprint = {1709.07374}, note = {arXiv:1709.07374v1} }
PDF
A semi-inclusive measurement of charged hadron multiplicities in deep inelastic muon scattering off an isoscalar target was performed using data collected by the COMPASS Collaboration at CERN. The following kinematic domain is covered by the data: photon virtuality $Q^{2}>1$ (GeV/$c$)$^2$, invariant mass of the hadronic system $W > 5$ GeV/$c^2$, Bjorken scaling variable in the range $0.003 < x < 0.4$, fraction of the virtual photon energy carried by the hadron in the range $0.2 < z < 0.8$, square of the hadron transverse momentum with respect to the virtual photon direction in the range 0.02 (GeV/$c)^2 < P_{\rm{hT}}^{2} < 3$ (GeV/$c$)$^2$. The multiplicities are presented as a function of $P_{\rm{hT}}^{2}$ in three-dimensional bins of $x$, $Q^2$, $z$ and compared to previous semi-inclusive measurements. We explore the small-$P_{\rm{hT}}^{2}$ region, i.e. $P_{\rm{hT}}^{2} < 1$ (GeV/$c$)$^2$, where hadron transverse momenta are expected to arise from non-perturbative effects, and also the domain of larger $P_{\rm{hT}}^{2}$, where contributions from higher-order perturbative QCD are expected to dominate. The multiplicities are fitted using a single-exponential function at small $P_{\rm{hT}}^{2}$ to study the dependence of the average transverse momentum $\langle P_{\rm{hT}}^{2}\rangle$ on $x$, $Q^2$ and $z$. The power-law behaviour of the multiplicities at large $P_{\rm{hT}}^{2}$ is investigated using various functional forms. The fits describe the data reasonably well over the full measured range.
New analysis of $\eta\pi$ tensor resonances measured at the COMPASS experiment
A. Jackura, C. Fernandez-Ramirez, M. Mikhasenko, A. Pilloni, V. Mathieu, J. Nys, V. Pauk, A. P. Szczepaniak, G. Fox, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, et al (217)
Jul 11 2017 hep-ph hep-ex arXiv:1707.02848v1

@misc{1707.02848, author = {A.~Jackura and C.~Fernandez-Ramirez and M.~Mikhasenko and A.~Pilloni and V.~Mathieu and J.~Nys and V.~Pauk and A.~P.~Szczepaniak and G.~Fox and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and T.~Schluter and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{N}ew analysis of $\eta\pi$ tensor resonances measured at the {COMPASS} experiment}, year = {2017}, eprint = {1707.02848}, note = {arXiv:1707.02848v1} }
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We present a new amplitude analysis of the $\eta\pi$ $D$-wave in $\pi^- p\to \eta\pi^- p$ measured by COMPASS. Employing an analytical model based on the principles of the relativistic $S$-matrix, we find two resonances that can be identified with the $a_2(1320)$ and the excited $a_2^\prime(1700)$, and perform a comprehensive analysis of their pole positions. For the mass and width of the $a_2$ we find $M=(1307 \pm 1 \pm 6)$~MeV and $\Gamma=(112 \pm 1 \pm 8)$~MeV, and for the excited state $a_2^\prime$ we obtain $M=(1720 \pm 10 \pm 60)$~MeV and $\Gamma=(280\pm 10 \pm 70)$~MeV, respectively.
Search for muoproduction of $X(3872)$ at COMPASS and indication of a new state $\widetilde{X}(3872)$
M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (208)
Jul 07 2017 hep-ex arXiv:1707.01796v2

@misc{1707.01796, author = {M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and A.~Bressan and M.~Buechele and V.E.~Burtsev and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and A.G.~Chumakov and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and R.R.~Dusaev and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and A.~Grasso and A.~Gridin and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and I.I.~Kuznetsov and A.~Kveton and A.A.~Lednev and E.A.~Levchenko and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and V.E.~Lyubovitskij and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and S.A.~Mamon and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and M.~Peskova and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and B.I.~Vasilishin and A.~Vauth and J.~Veloso and A.Vidon and M.~Virius and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{S}earch for muoproduction of ${X}(3872)$ at {COMPASS} and indication of a new state $\widetilde{{X}}(3872)$}, year = {2017}, eprint = {1707.01796}, doi = {10.1016/j.physletb.2018.07.008}, note = {arXiv:1707.01796v2} }
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We have searched for exclusive production of exotic charmonia in the reaction $\mu^+~N \rightarrow \mu^+ (J\!/\!\psi\pi^+\pi^-)\pi^{\pm}~N'$ using COMPASS data collected with incoming muons of 160 GeV/$c$ and 200 GeV/$c$ momentum. In the $J\!/\!\psi\pi^+\pi^-$ mass distribution we observe a signal with a statistical significance of 4.1 $\sigma$. Its mass and width are consistent with those of the $X(3872)$. The shape of the $\pi^+\pi^-$ mass distribution from the observed decay into $J\!/\!\psi\pi^+\pi^-$ shows disagreement with previous observations for $X(3872)$. The observed signal may be interpreted as a possible evidence of a new charmonium state. It could be associated with a neutral partner of $X(3872)$ with $C = -1$ predicted by a tetraquark model. The product of cross section and branching fraction of the decay of the observed state into $J\!/\!\psi\pi^+\pi^-$ is determined to be 71$\pm$28(stat)$\pm$39(syst) pb.
First measurement of transverse-spin-dependent azimuthal asymmetries in the Drell-Yan process
Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (200)
Apr 04 2017 hep-ex hep-ph arXiv:1704.00488v1

@misc{1704.00488, author = {Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and Z.~Kral and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.~Kveton and A.A.~Lednev and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and M.~Roskot and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and A.~Thiel and J.~Tomsa and F.~Tosello and V.~Tskhay and S.~Uhl and A.~Vauth and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{F}irst measurement of transverse-spin-dependent azimuthal asymmetries in the {D}rell-{Y}an process}, year = {2017}, eprint = {1704.00488}, note = {arXiv:1704.00488v1} }
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The first measurement of transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan (DY) process is reported. We use the CERN SPS 190 GeV/$c$, $\pi^{-}$ beam and a transversely polarized ammonia target. Three azimuthal asymmetries giving access to different transverse-momentum-dependent (TMD) parton distribution functions (PDFs) are extracted using dimuon events with invariant mass between 4.3 GeV/$c^2$ and 8.5 GeV/$c^2$. The observed sign of the Sivers asymmetry is found to be consistent with the fundamental prediction of Quantum Chromodynamics (QCD) that the Sivers TMD PDFs extracted from DY have a sign opposite to the one extracted from semi-inclusive deep-inelastic scattering (SIDIS) data. We present two other asymmetries originating from the pion Boer-Mulders TMD PDFs convoluted with either the nucleon transversity or pretzelosity TMD PDFs. These DY results are obtained at a hard scale comparable to that of a recent COMPASS SIDIS measurement and hence allow unique tests of fundamental QCD universality predictions.
First measurement of the Sivers asymmetry for gluons from SIDIS data
C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, A. Antoshkin, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, et al (207)
Jan 11 2017 hep-ex hep-ph arXiv:1701.02453v1

@misc{1701.02453, author = {C.~Adolph and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and A.~Antoshkin and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rogacheva and M.~Roskot and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and A.~Thiel and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki and A.~Zink}, title = {{F}irst measurement of the {S}ivers asymmetry for gluons from {SIDIS} data}, year = {2017}, eprint = {1701.02453}, note = {arXiv:1701.02453v1} }
PDF
The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. It was extracted from measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it turned out to be non-zero for quarks. In this letter the evaluation of the Sivers asymmetry for gluons in the same process is presented. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon-gluon fusion, QCD Compton scattering and leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simultaneously extracted using the LEPTO event generator and a neural network approach. The method is applied to samples of events containing at least two hadrons with large transverse momentum from the COMPASS data taken with a 160 GeV/$c$ muon beam scattered off transversely polarised deuterons and protons. With a significance of more than two standard deviations a negative value is obtained for the gluon Sivers asymmetry. The result of a similar analysis for a Collins-like asymmetry for gluons is consistent with zero.
Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the Bjorken sum rule
C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (207)
Dec 05 2016 hep-ex arXiv:1612.00620v1

@misc{1612.00620, author = {C.~Adolph and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and A.~Kerbizi and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and A.~Thiel and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and R.~Windmolders and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki and A.~Zink}, title = {{F}inal {COMPASS} results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the {B}jorken sum rule}, year = {2016}, eprint = {1612.00620}, note = {arXiv:1612.00620v1} }
PDF
Final results are presented from the inclusive measurement of deep-inelastic polarised-muon scattering on longitudinally polarised deuterons using a $^6$LiD target. The data were taken at $160~{\rm GeV}$ beam energy and the results are shown for the kinematic range $1~({\rm GeV}/c)^2 < Q^2 < 100~({\rm GeV}/c)^2$ in photon virtuality, $0.004<x<0.7$ in the Bjorken scaling variable and $W > 4~{\rm GeV}/c^2$ in the mass of the hadronic final state. The deuteron double-spin asymmetry $A_1^{\rm d}$ and the deuteron longitudinal-spin structure function $g_1^{\rm d}$ are presented in bins of $x$ and $Q^2$. Towards lowest accessible values of $x$, $g_1^{\rm d}$ decreases and becomes consistent with zero within uncertainties. The presented final $g_1^{\rm d}$ values together with the recently published final $g_1^{\rm p}$ values of COMPASS are used to again evaluate the Bjorken sum rule and perform the QCD fit to the $g_1$ world data at next-to-leading order of the strong coupling constant. In both cases, changes in central values of the resulting numbers are well within statistical uncertainties. The flavour-singlet axial charge $a_0$, which is identified in the $\overline{\rm MS}$ renormalisation scheme with the total contribution of quark helicities to the nucleon spin, is extracted from only the COMPASS deuteron data with negligible extrapolation uncertainty: $a_0 (Q^2 = 3~({\rm GeV}/c)^2) = 0.32 \pm 0.02_{\rm stat} \pm0.04_{\rm syst} \pm 0.05_{\rm evol}$. Together with the recent results on the proton spin structure function $g_1^{\rm p}$, the results on $g_1^{\rm d}$ constitute the COMPASS legacy on the measurements of $g_1$ through inclusive spin-dependent deep inelastic scattering.
Sivers asymmetry extracted in SIDIS at the hard scale of the Drell-Yan process at COMPASS
C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (207)
Sep 26 2016 hep-ex hep-ph arXiv:1609.07374v2

@misc{1609.07374, author = {C.~Adolph and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and A.~Thiel and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki and A.~Zink}, title = {{S}ivers asymmetry extracted in {SIDIS} at the hard scale of the {D}rell-{Y}an process at {COMPASS}}, year = {2016}, eprint = {1609.07374}, doi = {10.1016/j.physletb.2017.04.042}, note = {arXiv:1609.07374v2} }
PDF
Proton transverse-spin azimuthal asymmetries are extracted from the COMPASS 2010 semi-inclusive hadron measurements in deep inelastic muon-nucleon scattering in those four regions of the photon virtuality $Q^2$, which correspond to the four regions of the di-muon mass $\sqrt{Q^2}$ used in the ongoing analysis of the COMPASS Drell-Yan measurements. This allows for a future direct comparison of the nucleon transverse-momentum-dependent parton distribution functions extracted from these two alternative measurements. Various two-dimensional kinematic dependences are presented for the azimuthal asymmetries induced by the Sivers transverse-momentum-dependent parton distribution function. The integrated Sivers asymmetries are found to be positive with an accuracy that appears to be sufficient to test the sign change of the Sivers function predicted by Quantum Chromodynamics.
Azimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons
C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, et al (205)
Sep 21 2016 hep-ex hep-ph arXiv:1609.06062v2

@misc{1609.06062, author = {C.~Adolph and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and J.~Giarra and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and A.~Thiel and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki and A.~Zink}, title = {{A}zimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons}, year = {2016}, eprint = {1609.06062}, note = {arXiv:1609.06062v2} }
PDF
Single hadron azimuthal asymmetries of positive and negative hadrons produced in muon semi-inclusive deep inelastic scattering off longitudinally polarised deuterons are determined using the 2006 COMPASS data and also combined all deuteron COMPASS data. For each hadron charge, the dependence of the azimuthal asymmetry on the hadron azimuthal angle $\phi$ is obtained by means of a five-parameter fitting function that besides a $\phi$-independent term includes four modulations predicted by theory: $\sin\phi$, $\sin 2 \phi$, $\sin 3\phi$ and $\cos\phi$. The amplitudes of the five terms have been extracted, first, for the hadrons in the whole available kinematic region. In further fits, performed for hadrons from a restricted kinematic region, the $\phi$-dependence is determined as a function of one of three variables (Bjorken-$x$, fractional energy of virtual photon taken by the outgoing hadron and hadron transverse momentum), while disregarding the others. Except the $\phi$-independent term, all the modulation amplitudes are very small, and no clear kinematic dependence could be observed within experimental uncertainties.
Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target
C. Adolph, J. Agarwala, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, K. Augsten, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, M. Ball, J. Barth, R. Beck, Y. Bedfer, et al (207)
Aug 25 2016 hep-ex nucl-ex arXiv:1608.06760v1

@misc{1608.06760, author = {C.~Adolph and J.~Agarwala and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and K.~Augsten and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and M.~Ball and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and M.~Bodlak and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and L.~Capozza and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and Ch.~Dreisbach and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and G.~Hamar and D.~von Harrach and F.H.~Heinsius and R.~Heitz and F.~Herrmann and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and V.~Jary and R.~Joosten and P.~Joeorg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and A.~Nagaytsev and F.~Nerling and D.~Neyret and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and E.~Seder and A.~Selyunin and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and A.~Srnka and D.~Steffen and M.~Stolarski and O.~Subrt and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and A.~Thiel and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and R.~Windmolders and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki and A.~Zink}, title = {{M}ultiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target}, year = {2016}, eprint = {1608.06760}, note = {arXiv:1608.06760v1} }
PDF
Precise measurements of charged-kaon multiplicities in deep inelastic scattering were performed. The results are presented in three-dimensional bins of the Bjorken scaling variable x, the relative virtual-photon energy y, and the fraction z of the virtual-photon energy carried by the produced hadron. The data were obtained by the COMPASS Collaboration by scattering 160 GeV muons off an isoscalar 6 LiD target. They cover the kinematic domain 1 (GeV/c)2 < Q2 < 60 (GeV/c)^2 in the photon virtuality, 0.004 < x < 0.4, 0.1 < y < 0.7, 0.20 < z < 0.85, and W > 5 GeV/c^2 in the invariant mass of the hadronic system. The results from the sum of the z-integrated K+ and K- multiplicities at high x point to a value of the non-strange quark fragmentation function larger than obtained by the earlier DSS fit.
Exclusive $\omega$ meson muoproduction on transversely polarised protons
C. Adolph, J. Agarwala, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, et al (209)
Jun 14 2016 hep-ex nucl-ex arXiv:1606.03725v2

@misc{1606.03725, author = {C.~Adolph and J.~Agarwala and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and R.~Heitz and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~dHose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and Y.-S.~Lian and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and M.~Meyer and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and N.~Pierre and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and E.~Seder and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and D.~Steffen and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and S.~Wallner and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{E}xclusive $\omega$ meson muoproduction on transversely polarised protons}, year = {2016}, eprint = {1606.03725}, doi = {10.1016/j.nuclphysb.2016.12.015}, note = {arXiv:1606.03725v2} }
PDF
Exclusive production of $\omega$ mesons was studied at the COMPASS experiment by scattering $160~\mathrm{GeV}/\mathit{c}$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured in the range of photon virtuality $1~(\mathrm{GeV}/\mathit{c})^2 < Q^2 < 10~(\mathrm{GeV}/\mathit{c})^2$, Bjorken scaling variable $0.003 < x_{\mathit{Bj}} < 0.3$ and transverse momentum squared of the $\omega$ meson $0.05~(\mathrm{GeV}/\mathit{c})^2 < p_{T}^{2} < 0.5~(\mathrm{GeV}/\mathit{c})^2$. The measured asymmetries are sensitive to the nucleon helicity-flip Generalised Parton Distributions (GPD) $E$ that are related to the orbital angular momentum of quarks, the chiral-odd GPDs $H_{T}$ that are related to the transversity Parton Distribution Functions, and the sign of the $\pi\omega$ transition form factor. The results are compared to recent calculations of a GPD-based model.
Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target
C. Adolph, J. Agarwala, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, et al (208)
Apr 12 2016 hep-ex nucl-ex arXiv:1604.02695v2

@misc{1604.02695, author = {C.~Adolph and J.~Agarwala and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and L.~Capozza and W.-C.~Chang and C.~Chatterjee and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and R.~Heitz and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~dHose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and R.~Kuhn and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.~Mikhasenko and E.~Mitrofanov and N.~Mitrofanov and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and E.~Seder and A.~Selyunin and O.Yu.~Shevchenko and D.~Steffen and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and T.~Weisrock and M.~Wilfert and R.~Windmolders and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{M}ultiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target}, year = {2016}, eprint = {1604.02695}, note = {arXiv:1604.02695v2} }
PDF
Multiplicities of charged pions and unidentified hadrons produced in deep-inelastic scattering were measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the relative hadron energy $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam and an isoscalar target ($^6$LiD). They cover the kinematic domain in the photon virtuality $Q^2$ > 1(GeV/c$)^2$, $0.004 < x < 0.4$, $0.2 < z < 0.85$ and $0.1 < y < 0.7$. In addition, a leading-order pQCD analysis was performed using the pion multiplicity results to extract quark fragmentation functions.
Leading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data
C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, et al (201)
Dec 17 2015 hep-ex hep-ph arXiv:1512.05053v2

@misc{1512.05053, author = {C.~Adolph and M.~Aghasyan and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and N.V.~Anfimov and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and W.-C.~Chang and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and R.~Heitz and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and R.~Joosten and P.~Joerg and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.M.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and Y.~Kulinich and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.V.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.~Mikhasenko and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and M.~Roskot and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rybnikov and A.~Rychter and R.~Salac and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and T.~Sawada and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and E.~Seder and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and J.~Smolik and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and M.~Tasevsky and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and J.~Vondra and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and P.~Zavada and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{L}eading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data}, year = {2015}, eprint = {1512.05053}, note = {arXiv:1512.05053v2} }
PDF
Using a novel analysis technique, the gluon polarisation in the nucleon is re-evaluated using the longitudinal double-spin asymmetry measured in the cross section of semi-inclusive single-hadron muoproduction with photon virtuality $Q^2>1~({\rm GeV}/c)^2$. The data were obtained by the COMPASS experiment at CERN using a 160 GeV/$c$ polarised muon beam impinging on a polarised $^6$LiD target. By analysing the full range in hadron transverse momentum $p_{\rm T}$, the different $p_{\rm T}$-dependences of the underlying processes are separated using a neural-network approach. In the absence of pQCD calculations at next-to-leading order in the selected kinematic domain, the gluon polarisation $\Delta g/g$ is evaluated at leading order in pQCD at a hard scale of $\mu^2= \langle Q^2 \rangle = 3 ({\rm GeV}/c)^2$. It is determined in three intervals of the nucleon momentum fraction carried by gluons, $x_{\rm g}$, covering the range $0.04 \!<\! x_{ \rm g}\! <\! 0.28$~ and does not exhibit a significant dependence on $x_{\rm g}$. The average over the three intervals, $\langle \Delta g/g \rangle = 0.113 \pm 0.038_{\rm (stat.)}\pm 0.036_{\rm (syst.)}$ at $\langle x_{\rm g} \rangle \approx 0.10$, suggests that the gluon polarisation is positive in the measured $x_{\rm g}$ range.
Longitudinal double spin asymmetries in single hadron quasi-real photoproduction at high $p_T$
COMPASS Collaboration, C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badełek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E.R. Bielert, R. Birsa, et al (191)
Sep 14 2015 hep-ex hep-ph arXiv:1509.03526v2

@misc{1509.03526, author = {COMPASS Collaboration and C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badełek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Büchele and E.~Burtin and W.-C.~Chang and M.~Chiosso and I.~Choi and S.-U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Dünnweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmüller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and R.~Joosten and P.~Jörg and E.~Kabuß and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Königsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Krämer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and N.~Kuchinski and R.~Kuhn and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matoušek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Nový and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pešek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schönning and S.~Schopferer and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{L}ongitudinal double spin asymmetries in single hadron quasi-real photoproduction at high $p_{T}$}, year = {2015}, eprint = {1509.03526}, note = {arXiv:1509.03526v2} }
PDF
We measured the longitudinal double spin asymmetries $A_{LL}$ for single hadron muo-production off protons and deuterons at photon virtuality $Q^2$ < 1(GeV/$\it c$)$^2$ for transverse hadron momenta $p_T$ in the range 0.7 GeV/$\it c$ to 4 GeV/$\it c$ . They were determined using COMPASS data taken with a polarised muon beam of 160 GeV/$\it c$ or 200 GeV/$\it c$ impinging on polarised $\mathrm{{}^6LiD}$ or $\mathrm{NH_3}$ targets. The experimental asymmetries are compared to next-to-leading order pQCD calculations, and are sensitive to the gluon polarisation $\Delta G$ inside the nucleon in the range of the nucleon momentum fraction carried by gluons $0.05 < x_g < 0.2$.
Resonance Production and $\pi\pi$ S-wave in $\pi^- + p \rightarrow \pi^- \pi^- \pi^+ + p_{recoil}$ at 190 GeV/c
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badełek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E.R. Bielert, R. Birsa, J. Bisplinghoff, et al (190)
Sep 04 2015 hep-ex hep-ph arXiv:1509.00992v2

@misc{1509.00992, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badełek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Büchele and E.~Burtin and W.-C.~Chang and M.~Chiosso and I.~Choi and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Dünnweber and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmüller and A.~Grasso and M.~Grosse Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~d'Hose and C.-Y.~Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and R.~Joosten and P.~Jörg and E.~Kabuß and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Königsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Krämer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matoušek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Nový and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pešek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and T.~Schlüter and K.~Schmidt and H.~Schmieden and K.~Schönning and S.~Schopferer and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and T.~Weisrock and M.~Wilfert and J.~ter Wolbeek and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{R}esonance {P}roduction and $\pi\pi$ {S}-wave in $\pi^- + p \rightarrow \pi^- \pi^- \pi^+ + p_{recoil}$ at 190 {G}e{V}/c}, year = {2015}, eprint = {1509.00992}, howpublished = {Phys. Rev. D 95, 032004 (2017)}, doi = {10.1103/PhysRevD.95.032004}, note = {arXiv:1509.00992v2} }
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The COMPASS collaboration has collected the currently largest data set on diffractively produced $\pi^-\pi^-\pi^+$ final states using a negative pion beam of 190 GeV/c momentum impinging on a stationary proton target. This data set allows for a systematic partial-wave analysis in 100 bins of three-pion mass, $0.5 < m_{3\pi} < 2.5$ GeV/c$^2$ , and in 11 bins of the reduced four-momentum transfer squared, $0.1 < t < 1.0$ (GeV/c)$^2$ . This two-dimensional analysis offers sensitivity to genuine one-step resonance production, i.e. the production of a state followed by its decay, as well as to more complex dynamical effects in nonresonant $3\pi$ production. In this paper, we present detailed studies on selected $3\pi$ partial waves with $J^{PC} = 0^{-+}$, $1^{++}$, $2^{-+}$, $2^{++}$, and $4^{++}$. In these waves, we observe the well-known ground-state mesons as well as a new narrow axial-vector meson $a_1(1420)$ decaying into $f_0(980) \pi$. In addition, we present the results of a novel method to extract the amplitude of the $\pi^-\pi^+$ subsystem with $I^{G}J^{PC} = 0^+ 0^{++}$ in various partial waves from the $\pi^-\pi^-\pi^+$ data. Evidence is found for correlation of the $f_0(980)$ and $f_0(1500)$ appearing as intermediate $\pi^- \pi^+$ isobars in the decay of the known $\pi(1800)$ and $\pi_2(1880)$.
Interplay among transversity induced asymmetries in hadron leptoproduction
Compass Collaboration, C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badelek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, R. Birsa, et al (190)
Jul 29 2015 hep-ex hep-ph arXiv:1507.07593v2

@misc{1507.07593, author = {Compass Collaboration and C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and W.~Augustyniak and A.~Austregesilo and C.D.R.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Büchele and E.~Burtin and W.-C.~Chang and M.~Chiosso and I.~Choi and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and N.~d'Hose and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmüller and A.~Grasso and M.~Grosse-Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and N.~Horikawa and C.-Yu Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jörg and R.~Joosten and E.~Kabuß and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Königsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Krämer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and B.~Marianski and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and P.~Montuenga and A.~Nagaytsev and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and G.~Nukazuka and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and G.~Pesaro and M.~Pesek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schönning and S.~Schopferer and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and T.~Weisrock and M.~Wilfert and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{I}nterplay among transversity induced asymmetries in hadron leptoproduction}, year = {2015}, eprint = {1507.07593}, note = {arXiv:1507.07593v2} }
PDF
In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows to establish quantitative relationships among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.
The Spin Structure Function $g_1^{\rm p}$ of the Proton and a Test of the Bjorken Sum Rule
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, C. Azevedo, B. Badelek, F. Balestra, J. Barth, G. Baum, G. R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, R. Birsa, J. Bisplinghoff, et al (187)
Apr 01 2015 hep-ex hep-ph arXiv:1503.08935v1

@misc{1503.08935, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and C.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and G.~R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and W.-C.~Chang and M.~Chiosso and I.~Choi and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and E.~Fuchey and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and F.~Giordano and I.~Gnesi and M.~Gorzellik and S.~Grabmüller and A.~Grasso and M.~Grosse-Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~d'Hose and C.-Yu Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jörg and R.~Joosten and E.~Kabuß and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and R.~Longo and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and F.~Tosello and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and T.~Weisrock and M.~Wilfert and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{T}he {S}pin {S}tructure {F}unction $g_1^{\rm p}$ of the {P}roton and a {T}est of the {B}jorken {S}um {R}ule}, year = {2015}, eprint = {1503.08935}, note = {arXiv:1503.08935v1} }
PDF
New results for the double spin asymmetry $A_1^{\rm p}$ and the proton longitudinal spin structure function $g_1^{\rm p}$ are presented. They were obtained by the COMPASS collaboration using polarised 200 GeV muons scattered off a longitudinally polarised NH$_3$ target. The data were collected in 2011 and complement those recorded in 2007 at 160\u2009GeV, in particular at lower values of $x$. They improve the statistical precision of $g_1^{\rm p}(x)$ by about a factor of two in the region $x\lesssim 0.02$. A next-to-leading order QCD fit to the $g_1$ world data is performed. It leads to a new determination of the quark spin contribution to the nucleon spin, $\Delta \Sigma$ ranging from 0.26 to 0.36, and to a re-evaluation of the first moment of $g_1^{\rm p}$. The uncertainty of $\Delta \Sigma$ is mostly due to the large uncertainty in the present determinations of the gluon helicity distribution. A new evaluation of the Bjorken sum rule based on the COMPASS results for the non-singlet structure function $g_1^{\rm NS}(x,Q^2)$ yields as ratio of the axial and vector coupling constants $|g_{\rm A}/g_{\rm V}| = 1.22 \pm 0.05~({\rm stat.}) \pm 0.10~({\rm syst.})$, which validates the sum rule to an accuracy of about 9\%.
Observation of a new narrow axial-vector meson $a_1(1420)$
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, C. Azevedo, B. Badelek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E. R. Bielert, R. Birsa, J. Bisplinghoff, M. Bodlak, et al (185)
Jan 26 2015 hep-ex arXiv:1501.05732v3

@misc{1501.05732, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and C.~Azevedo and B.~Badelek and F.~Balestra and J.~Barth and R.~Beck and Y.~Bedfer and J.~Bernhard and K.~Bicker and E.~R.~Bielert and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and W.-C.~Chang and M.~Chiosso and I.~Choi and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and W Duennweber and V.~Duic and M.~Dziewiecki and A.~Efremov and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and I.~Gnesi and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Grosse-Perdekamp and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~Hahne and D.~von Harrach and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and N.~Horikawa and N.~d'Hose and C.-Yu Hsieh and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and P.~Kremser and F.~Krinner and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makins and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and D.~Panzieri and B.~Parsamyan and S.~Paul and J.-C.~Peng and F.~Pereira and M.~Pesek and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and C.~Riedl and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and C.~Santos and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and T.~Schlueter and A.~Selyunin and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and V.~Tskhay and S.~Uhl and J.~Veloso and M.~Virius and S.~Wallner and T.~Weisrock and M.~Wilfert and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{O}bservation of a new narrow axial-vector meson $a_1(1420)$}, year = {2015}, eprint = {1501.05732}, howpublished = {Phys. Rev. Lett. 115, 082001 (2015)}, doi = {10.1103/PhysRevLett.115.082001}, note = {arXiv:1501.05732v3} }
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The COMPASS collaboration at CERN has measured diffractive dissociation of 190 GeV/$c$ pions into the $\pi^-\pi^-\pi^+$ final state using a stationary hydrogen target. A partial-wave analysis (PWA) was performed in bins of $3\pi$ mass and four-momentum transfer using the isobar model and the so far largest PWA model consisting of 88 waves. A narrow $J^{PC} = 1^{++}$ signal is observed in the $f_0(980)\,\pi$ channel. We present a resonance-model study of a subset of the spin-density matrix selecting $3\pi$ states with $J^{PC} = 2^{++}$ and $4^{++}$ decaying into $\rho(770)\,\pi$ and with $J^{PC} = 1^{++}$ decaying into $f_0(980)\,\pi$. We identify a new $a_1$ meson with mass $(1414^{+15}_{-13})$ MeV/$c^2$ and width $(153^{+8}_{-23})$ MeV/$c^2$. Within the final states investigated in our analysis, we observe the new $a_1(1420)$ decaying only into $f_0(980)\,\pi$, suggesting its exotic nature.
The COMPASS Setup for Physics with Hadron Beams
Ph. Abbon, C. Adolph, R. Akhunzyanov, Yu. Alexandrov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, E.R. Bielert, et al (212)
Oct 08 2014 physics.ins-det hep-ex arXiv:1410.1797v1

@misc{1410.1797, author = {Ph.~Abbon and C.~Adolph and R.~Akhunzyanov and Yu.~Alexandrov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and E.R.~Bielert and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and P.~Ciliberti and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.~Colantoni and D.~Cotte and M.L.~Crespo and Q.~Curiel and T.~Dafni and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and D.~Desforge and A.M.~Dinkelbach and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and D.~Durand and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and L.~Gatignon and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and A.~Giganon and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and M.~Gregori and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and R.~Kuhn and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and J.~Marroncle and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Menon and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and M.A.~Moinester and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and G.~Pesaro and V.~Pesaro and D.V.~Peshekhonov and C.~Pires and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and J-M.~Reymond and E.~Rocco and N.S.~Rossiyskaya and J.-Y.~Rousse and D.I.~Ryabchikov and A.~Rychter and A.~Samartsev and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and V.~Tskhay and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and Q.~Weitzel and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{T}he {COMPASS} {S}etup for {P}hysics with {H}adron {B}eams}, year = {2014}, eprint = {1410.1797}, note = {arXiv:1410.1797v1} }
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The main characteristics of the COMPASS experimental setup for physics with hadron beams are described. This setup was designed to perform exclusive measurements of processes with several charged and/or neutral particles in the final state. Making use of a large part of the apparatus that was previously built for spin structure studies with a muon beam, it also features a new target system as well as new or upgraded detectors. The hadron setup is able to operate at the high incident hadron flux available at CERN. It is characterised by large angular and momentum coverages, large and nearly flat acceptances, and good two and three-particle mass resolutions. In 2008 and 2009 it was successfully used with positive and negative hadron beams and with liquid hydrogen and solid nuclear targets. This article describes the new and upgraded detectors and auxiliary equipment, outlines the reconstruction procedures used, and summarises the general performance of the setup.
Odd and Even Partial Waves of $\eta\pi^-$ and $\eta'\pi^-$ in $\pi^-p\to\eta^{(\prime)}\pi^-p$ at $191\,\textrm{GeV}/c$
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, E. R. Bielert, J. Bieling, R. Birsa, et al (189)
Aug 20 2014 hep-ex nucl-ex arXiv:1408.4286v1

@misc{1408.4286, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and E.~R.~Bielert and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{O}dd and {E}ven {P}artial {W}aves of $\eta\pi^-$ and $\eta'\pi^-$ in $\pi^-p\to\eta^{(\prime)}\pi^-p$ at $191\,\textrm{{G}e{V}}/c$}, year = {2014}, eprint = {1408.4286}, note = {arXiv:1408.4286v1} }
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Exclusive production of $\eta\pi^-$ and $\eta'\pi^-$ has been studied with a $191\,\textrm{GeV}/c$ $\pi^-$ beam impinging on a hydrogen target at COMPASS (CERN). Partial-wave analyses reveal different odd/even angular momentum ($L$) characteristics in the inspected invariant mass range up to $3\,\textrm{GeV}/c^2$. A striking similarity between the two systems is observed for the $L=2,4,6$ intensities (scaled by kinematical factors) and the relative phases. The known resonances $a_2(1320)$ and $a_4(2040)$ are in line with this similarity. In contrast, a strong enhancement of $\eta'\pi^-$ over $\eta\pi^-$ is found for the $L=1,3,5$ waves, which carry non-$q\bar q$ quantum numbers. The $L=1$ intensity peaks at $1.7\,\textrm{GeV}/c^2$ in $\eta'\pi^-$ and at $1.4\,\textrm{GeV}/c^2$ in $\eta\pi^-$, the corresponding phase motions with respect to $L=2$ are different.
Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised proton
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, E. R. Bielert, J. Bieling, R. Birsa, et al (189)
Aug 20 2014 hep-ex arXiv:1408.4405v1

@misc{1408.4405, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and E.~R.~Bielert and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{C}ollins and {S}ivers asymmetries in muonproduction of pions and kaons off transversely polarised proton}, year = {2014}, eprint = {1408.4405}, note = {arXiv:1408.4405v1} }
PDF
Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise.
Search for exclusive photoproduction of Z$_c^{\pm}$(3900) at COMPASS
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, E. R. Bielert, J. Bieling, R. Birsa, et al (189)
Jul 24 2014 hep-ex arXiv:1407.6186v1

@misc{1407.6186, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and E.~R.~Bielert and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and T.~Grussenmeyer and A.~Guskov and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and D.V.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{S}earch for exclusive photoproduction of {Z}$_c^{\pm}$(3900) at {COMPASS}}, year = {2014}, eprint = {1407.6186}, note = {arXiv:1407.6186v1} }
PDF
A search for the exclusive production of the $Z_c^{\pm}(3900)$ hadron by virtual photons has been performed in the channel $Z_c^{\pm}(3900)\rightarrow J/\psi \pi^{\pm}$. The data cover the range from 7 GeV to 19 GeV in the centre-of-mass energy of the photon-nucleon system. The full set of the COMPASS data set collected with a muon beam between 2002 and 2011 has been used. An upper limit for the ratio $BR(Z_c^{\pm}(3900)\rightarrow J/\psi \pi^{\pm} )\times \sigma_{ \gamma~N \rightarrow Z_c^{\pm}(3900)~ N} /\sigma_{\gamma~N \rightarrow J/\psi~ N}$ of $3.7\times10^{-3}$ has been established at the confidence level of 90%.
Spin alignment and violation of the OZI rule in exclusive $\omega$ and $\phi$ production in pp collisions
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (189)
May 27 2014 hep-ex nucl-ex arXiv:1405.6376v1

@misc{1405.6376, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and r.~M.~Finger and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and T.~Grussenmeyer and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and h.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and u.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and u.A.~Khokhlov and u.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and u.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and D.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{S}pin alignment and violation of the {OZI} rule in exclusive $\omega$ and $\phi$ production in pp collisions}, year = {2014}, eprint = {1405.6376}, note = {arXiv:1405.6376v1} }
PDF
Exclusive production of the isoscalar vector mesons $\omega$ and $\phi$ is measured with a 190 GeV$/c$ proton beam impinging on a liquid hydrogen target. Cross section ratios are determined in three intervals of the Feynman variable $x_{F}$ of the fast proton. A significant violation of the OZI rule is found, confirming earlier findings. Its kinematic dependence on $x_{F}$ and on the invariant mass $M_{p\mathrm{V}}$ of the system formed by fast proton $p_\mathrm{fast}$ and vector meson $V$ is discussed in terms of diffractive production of $p_\mathrm{fast}V$ resonances in competition with central production. The measurement of the spin density matrix element $\rho_{00}$ of the vector mesons in different selected reference frames provides another handle to distinguish the contributions of these two major reaction types. Again, dependences of the alignment on $x_{F}$ and on $M_{p\mathrm{V}}$ are found. Most of the observations can be traced back to the existence of several excited baryon states contributing to $\omega$ production which are absent in the case of the $\phi$ meson. Removing the low-mass $M_{p\mathrm{V}}$ resonant region, the OZI rule is found to be violated by a factor of eight, independently of $x_\mathrm{F}$.
Measurement of the charged-pion polarisability
C. Adolph, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (193)
May 27 2014 hep-ex nucl-ex arXiv:1405.6377v2

@misc{1405.6377, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alexeev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.~Colantoni and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and A.M.~Dinkelbach and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~jr.~Finger and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and T.~Grussenmeyer and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and R.~Kuhn and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and M.~Levillain and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and M.A.~Moinester and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and I.~Orlov and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and D.~Peshekhonov and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and C.~Regali and G.~Reicherz and E.~Rocco and N.S.~Rossiyskaya and D.I.~Ryabchikov and A.~Rychter and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and A.~Zink}, title = {{M}easurement of the charged-pion polarisability}, year = {2014}, eprint = {1405.6377}, note = {arXiv:1405.6377v2} }
PDF
The COMPASS collaboration at CERN has investigated pion Compton scattering, $\pi^-\gamma\rightarrow \pi^-\gamma$, at centre-of-mass energy below 3.5 pion masses. The process is embedded in the reaction $\pi^-\mathrm{Ni}\rightarrow\pi^-\gamma\;\mathrm{Ni}$, which is initiated by 190\u2009GeV pions impinging on a nickel target. The exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, $Q^2<0.0015$\,(GeV/$c$)$^2$. From a sample of 63\u2009000 events the pion electric polarisability is determined to be $\alpha_\pi\ =\ (\,2.0\ \pm\ 0.6_{\mbox{\scriptsize stat}}\ \pm\ 0.7_{\mbox{\scriptsize syst}}\,) \times 10^{-4}\,\mbox{fm}^3$ under the assumption $\alpha_\pi=-\beta_\pi$, which relates the electric and magnetic dipole polarisabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction, that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambigiously known, was performed for an independent estimate of the systematic uncertainty.
Measurement of radiative widths of $a_2(1320)$ and $\pi_2(1670)$
C. Adolph, R. Akhunzyanov, M.G. Alekseev, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (189)
Mar 12 2014 hep-ex hep-ph arXiv:1403.2644v1

@misc{1403.2644, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alekseev and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger~jr.~and H.~Fischer and C.~Franco and N.~du~Fresne~von~Hohenesche and J.M.~Friedrich and V.~Frolov and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and Z.~Kral and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and I.~Orlov and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and M.~Pesek and S.~Platchkov and J.~Pochodzalla and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and A.~Rychter and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabelski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter~Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and J.~Vondra and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki.}, title = {{M}easurement of radiative widths of $a_2(1320)$ and $\pi_2(1670)$}, year = {2014}, eprint = {1403.2644}, note = {arXiv:1403.2644v1} }
PDF
The COMPASS Collaboration at CERN has investigated the reaction $\pi^- \gamma \rightarrow \pi^-\pi^-\pi^+$ embedded in the Primakoff reaction of $190~\textrm{GeV}$ pions scattering in the Coulomb field of a lead target, $\pi^- \text{Pb} \rightarrow \pi^-\pi^-\pi^+ \text{Pb}$. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at momentum transfer below $0.001~(\text{GeV}/c)^2$. Using a partial-wave analysis the amplitudes and relative phases of the $a_2(1320)$ and $\pi_2(1670)$ mesons have been extracted, and the Coulomb and the diffractive contributions have been disentangled. Measuring absolute production cross sections we have determined the radiative width of the $a_2(1320)$ to be $\Gamma_0(a_2(1320) \rightarrow \pi\gamma) = (358 \pm 6_{\textrm{stat}} \pm 42_{\textrm{syst}})~\textrm{keV}$. As the first measurement, $\Gamma_0(\pi_2(1670) \rightarrow \pi\gamma) = (181 \pm 11_{\textrm{stat}} \pm 27_{\textrm{syst}})~\textrm{keV} \cdot (\textrm{BR}^{\textrm{PDG}}_{f_2 \pi}/\textrm{BR}_{f_2 \pi})$ is obtained for the radiative width of the $\pi_2(1670)$, where in this analysis the branching ratio $\textrm{BR}^{\textrm{PDG}}_{f_2 \pi}=0.56$ has been used. We compare these values to previous measurements and theoretical predictions.
A high-statistics measurement of transverse spin effects in dihadron production from muon-proton semi-inclusive deep-inelastic scattering
C. Adolph, R. Akhunzyanov, M.G. Alekseev, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, et al (201)
Jan 31 2014 hep-ex hep-ph arXiv:1401.7873v1

@misc{1401.7873, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alekseev and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and Z.~Kral and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and I.~Orlov and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and M.~Pesek and D.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and A.~Rychter and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabeleski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and J.~Vondra and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki}, title = {{A} high-statistics measurement of transverse spin effects in dihadron production from muon-proton semi-inclusive deep-inelastic scattering}, year = {2014}, eprint = {1401.7873}, note = {arXiv:1401.7873v1} }
PDF
A measurement of the azimuthal asymmetry in dihadron production in deep-inelastic scattering of muons on transversely polarised proton (NH$_{3}$) targets are presented. They provide independent access to the transversity distribution functions through the measurement of the Collins asymmetry in single hadron production. The data were taken in the year $2010$ with the COMPASS spectrometer using a $160\,\mbox{GeV}/c$ muon beam of the CERN SPS, increasing by a factor of about three the available statistics of the previously published data taken in the year $2007$. The measured sizeable asymmetry is in good agreement with the published data. An approximate equality of the Collins asymmetry and the dihadron asymmetry is observed, suggesting a common physical mechanism in the underlying fragmentation.
Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons
C. Adolph, R. Akhunzyanov, M.G. Alekseev, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, V. Andrieux, V. Anosov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, R. Beck, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, et al (201)
Jan 27 2014 hep-ex arXiv:1401.6284v1

@misc{1401.6284, author = {C.~Adolph and R.~Akhunzyanov and M.G.~Alekseev and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and V.~Anosov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and R.~Beck and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Bodlak and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and Q.~Curiel and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and M.~Gorzellik and S.~Grabmueller and A.~Grasso and B.~Grube and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and R.~Hashimoto and F.H.~Heinsius and F.~Herrmann and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and A.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and P.~Joerg and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and Z.~Kral and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and I.~Orlov and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and M.~Pesek and D.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and A.~Rychter and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and A.~Szabeleski and T.~Szameitat and P.~Sznajder and S.~Takekawa and J.~ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and J.~Vondra and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki}, title = {{M}easurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons}, year = {2014}, eprint = {1401.6284}, note = {arXiv:1401.6284v1} }
PDF
Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS muon beam at $160$ GeV/c and a $^6$LiD target. The amplitudes of the three azimuthal modulations $\cos\phi_h$, $\cos2\phi_h$ and $\sin\phi_h$ were obtained binning the data separately in each of the relevant kinematic variables $x$, $z$ or $p_T^{\,h}$ and binning in a three-dimensional grid of these three variables. The amplitudes of the $\cos \phi_h$ and $\cos 2\phi_h$ modulations show strong kinematic dependencies both for positive and negative hadrons.
Transverse target spin asymmetries in exclusive $\rho^0$ muoproduction
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, V. Andrieux, A. Austregesilo, B. Badellek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (193)
Oct 08 2013 hep-ex nucl-ex arXiv:1310.1454v2

@misc{1310.1454, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and A.~Austregesilo and B.~Badellek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and D.~Hahne and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and C.~Marchand and A.~Martin and J.~Marzec and J.~Matousek and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Morreale and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and M.~Pesek and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and L.~Schmitt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and J.~Vondra and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{T}ransverse target spin asymmetries in exclusive $\rho^0$ muoproduction}, year = {2013}, eprint = {1310.1454}, note = {arXiv:1310.1454v2} }
PDF
Exclusive production of $\rho^0$ mesons was studied at the COMPASS experiment by scattering 160 GeV/$c$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of $Q^2$, $x_{Bj}$, or $p_{T}^{2}$. The $\sin \phi_S$ asymmetry is found to be $-0.019 \pm 0.008(stat.) \pm 0.003(syst.)$. All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions.
Hadron Transverse Momentum Distributions in Muon Deep Inelastic Scattering at 160 GeV/$c$
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, V. Andrieux, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (191)
Jun 03 2013 hep-ex hep-ph arXiv:1305.7317v1

@misc{1305.7317, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Morreale and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and L.~Schmitt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wiślicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{H}adron {T}ransverse {M}omentum {D}istributions in {M}uon {D}eep {I}nelastic {S}cattering at 160 {G}e{V}/$c$}, year = {2013}, eprint = {1305.7317}, howpublished = {Eur. Phys. J. C (2013) 73:2531}, doi = {10.1140/epjc/s10052-013-2531-6}, note = {arXiv:1305.7317v1} }
PDF
Multiplicities of charged hadrons produced in deep inelastic muon scattering off a $^6$LiD target have been measured as a function of the DIS variables $x_{Bj}$, $Q^2$, $W^2$ and the final state hadron variables $p_T$ and $z$. The $p_T^2$ distributions are fitted with a single exponential function at low values of $p_T^2$ to determine the dependence of $\langle p_T^2 \rangle$ on $x_{Bj}$, $Q^2$, $W^2$ and $z$. The $z$-dependence of $\langle p_T^2 \rangle$ is shown to be a potential tool to extract the average intrinsic transverse momentum squared of partons, $\langle k_{\perp}^2 \rangle$, as a function of $x_{Bj}$ and $Q^2$ in a leading order QCD parton model.
Study of \Sigma(1385) and \Xi(1321) hyperon and antihyperon production in deep inelastic muon scattering
C. Adolph, M. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, P. Bordalo, et al (187)
Apr 04 2013 hep-ex nucl-ex arXiv:1304.0952v2

@misc{1304.0952, author = {C.~Adolph and M.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Morreale and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and L.~Schmitt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{S}tudy of \{S}igma(1385) and \{X}i(1321) hyperon and antihyperon production in deep inelastic muon scattering}, year = {2013}, eprint = {1304.0952}, note = {arXiv:1304.0952v2} }
PDF
Large samples of \Lambda, \Sigma(1385) and \Xi(1321) hyperons produced in deep-inelastic muon scattering off a ^6LiD target were collected with the COMPASS experimental setup at CERN. The relative yields of \Sigma(1385)^+, \Sigma(1385)^-, \bar\Sigma(1385)^-, \bar\Sigma(1385)^+, \Xi(1321)^-, and \bar\Xi(1321)^+ hyperons decaying into \Lambda(\bar\Lambda)\pi were measured. The heavy hyperon to \Lambda and heavy antihyperon to \bar\Lambda yield ratios were found to be in the range 3.8% to 5.6% with a relative uncertainty of about 10%. They were used to tune the parameters relevant for strange particle production of the LEPTO Monte Carlo generator.
Leading and Next-to-Leading Order Gluon Polarisation in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction
C. Adolph, M. G. Alekseev, V. Yu. Alexakhin, Yu. Alexandrov, G. D. Alexeev, A. Amoroso, A. A. Antonov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, et al (201)
Nov 30 2012 hep-ex arXiv:1211.6849v2

@misc{1211.6849, author = {C.~Adolph and M.~G.~Alekseev and V.~Yu.~Alexakhin and Yu.~Alexandrov and G.~D.~Alexeev and A.~Amoroso and A.~A.~Antonov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.~U.~Chung and A.~Cicuttin and M.~L.~Crespo and S.~Dalla Torre and S.~Das and S.~S.~Dasgupta and S.~Dasgupta and O.~Yu.~Denisov and L.~Dhara and S.~V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.~D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger Jr and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.~M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.~H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Huber and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.~V.~Khaustov and Yu.~A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.~F.~Konstantinov and A.~Korzenev and A.~M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.~V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.~A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.~V.~Mikhailov and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.~I.~Nikolaenko and W.-D.~Nowak and A.~S.~Nunes and A.~G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.~V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.~A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and E.~Rocco and E.~Rondio and N.~S.~Rossiyskaya and D.~I.~Ryabchikov and V.~D.~Samoylenko and A.~Sandacz and M.~G.~Sapozhnikov and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and L.~Schmitt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.~Yu.~Shevchenko and L.~Silva and L.~Sinha and A.~N.~Sissakian and M.~Slunecka and G.~I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.~G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.~V.~Vlassov and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{L}eading and {N}ext-to-{L}eading {O}rder {G}luon {P}olarisation in the {N}ucleon and {L}ongitudinal {D}ouble {S}pin {A}symmetries from {O}pen {C}harm {M}uoproduction}, year = {2012}, eprint = {1211.6849}, howpublished = {PHYSICALREVIEWD87,052018(2013)}, doi = {10.1103/PhysRevD.87.052018}, note = {arXiv:1211.6849v2} }
PDF
The gluon polarisation in the nucleon was measured using open charm production by scattering 160 GeV/c polarised muons off longitudinally polarised protons or deuterons. The data were taken by the COMPASS collaboration between 2002 and 2007. A detailed account is given of the analysis method that includes the application of neural networks. Several decay channels of D^0 mesons are investigated. Longitudinal spin asymmetries of the D meson production cross-sections are extracted in bins of D^0 transverse momentum and energy. At leading order QCD accuracy the average gluon polarisation is determined as (Delta g/G)^LO=-0.06 +/- 0.21 (stat.) +/- 0.08 (syst.) at the scale <mu^2> ~13 (GeV/c)^2 and an average gluon momentum fraction <x>~ 0.11. For the first time, the average gluon polarisation is also obtained at next-to-leading order QCD accuracy as (Delta g/G)^NLO = -0.13 +/- 0.15 (stat.) +/- 0.15 (syst.) at the scale <mu^2> ~ 13 (\GeV/c)^2 and <x> ~ 0.20.
D* and D Meson Production in Muon Nucleon Interactions at 160 GeV/c
C. Adolph, M. G. Alekseev, V. Yu. Alexakhin, Yu. Alexandrov, G. D. Alexeev, A. Amoroso, A. A. Antonov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, et al (201)
Nov 08 2012 hep-ex arXiv:1211.1575v2

@misc{1211.1575, author = {C.~Adolph and M.~G.~Alekseev and V.~Yu.~Alexakhin and Yu.~Alexandrov and G.~D.~Alexeev and A.~Amoroso and A.~A.~Antonov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.~U.~Chung and A.~Cicuttin and M.~L.~Crespo and S.~Dalla Torre and S.~Das and S.~S.~Dasgupta and S.~Dasgupta and O.~Yu.~Denisov and L.~Dhara and S.~V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.~D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger Jr and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.~M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.~H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Huber and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.~V.~Khaustov and Yu.~A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.~F.~Konstantinov and A.~Korzenev and A.~M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.~V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.~A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.~V.~Mikhailov and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.~I.~Nikolaenko and W.-D.~Nowak and A.~S.~Nunes and A.~G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.~V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.~A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and E.~Rocco and E.~Rondio and N.~S.~Rossiyskaya and D.~I.~Ryabchikov and V.~D.~Samoylenko and A.~Sandacz and M.~G.~Sapozhnikov and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and L.~Schmitt and H.~Schmieden and K.~Schoenning and S.~Schopferer and M.~Schott and O.~Yu.~Shevchenko and L.~Silva and L.~Sinha and A.~N.~Sissakian and M.~Slunecka and G.~I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.~G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.~V.~Vlassov and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{D}* and {D} {M}eson {P}roduction in {M}uon {N}ucleon {I}nteractions at 160 {G}e{V}/c}, year = {2012}, eprint = {1211.1575}, note = {arXiv:1211.1575v2} }
PDF
The production of D* and D mesons in inelastic scattering of 160 GeV/c muons off a ^6LiD target has been investigated with the COMPASS spectrometer at CERN for 0.003 (GeV/c)^2 < Q^2 < 10 (GeV/c)^2 and 3x10^-5< x_Bj < 0.1. The study is based on 8100 events where a D^0 or anti D^0 is detected subsequently to a D*+ or D*- decay, and on 34000 events, where only a D^0 or anti D^0 is detected. Kinematic distributions of D*, D and K*_2 are given as a function of their energy E, transverse momentum p_T, energy fraction z, and of the virtual photon variables nu, Q^2 and x_Bj. Semi-inclusive differential D* production cross-sections are compared with theoretical predictions for D* production via photon-gluon fusion into open charm. The total observed production cross-section for D*+/- mesons with laboratory energies between 22 and 86 GeV is 1.9 nb. Significant cross-section asymmetries are observed between D*+ and D*- production for nu<40 GeV and z>0.6.
Exclusive rho^0 muoproduction on transversely polarised protons and deuterons
C. Adolph, M. G. Alekseev, V. Yu. Alexakhin, Yu. Alexandrov, G. D. Alexeev, A. Amoroso, A. A. Antonov, A. Austregesilo, B. Badełek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (201)
Jul 19 2012 hep-ex arXiv:1207.4301v2

@misc{1207.4301, author = {C.~Adolph and M.~G.~Alekseev and V.~Yu.~Alexakhin and Yu.~Alexandrov and G.~D.~Alexeev and A.~Amoroso and A.~A.~Antonov and A.~Austregesilo and B.~Badełek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Büchele and E.~Burtin and L.~Capozza and M.~Chiosso and S.~U.~Chung and A.~Cicuttin and M.~L.~Crespo and S.~Dalla Torre and S.~Das and S.~S.~Dasgupta and S.~Dasgupta and O.~Yu.~Denisov and L.~Dhara and S.~V.~Donskov and N.~Doshita and V.~Duic and W.~Dünnweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.~D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger Jr and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.~M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.~P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmüller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthörl and F.~Haas and D.~von Harrach and F.~H.~Heinsius and F.~Herrmann and C.~Heß and F.~Hinterberger and N.~Horikawa and Ch.~Höppner and N.~d'Hose and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and G.~Jegou and R.~Joosten and E.~Kabuß and D.~Kang and B.~Ketzer and G.~V.~Khaustov and Yu.~A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo and K.~Königsmann and I.~Konorov and V.~F.~Konstantinov and A.~Korzenev and A.~M.~Kotzinian and O.~Kouznetsov and M.~Krämer and Z.~V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.~A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.~V.~Mikhailov and M.~A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and T.~Negrini and F.~Nerling and S.~Neubert and D.~Neyret and V.~I.~Nikolaenko and W.-D.~Nowak and A.~S.~Nunes and A.~G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.~V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.~A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and N.~S.~Rossiyskaya and D.~I.~Ryabchikov and V.~D.~Samoylenko and A.~Sandacz and M.~G.~Sapozhnikov and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlüter and K.~Schmidt and L.~Schmitt and K.~Schönning and S.~Schopferer and M.~Schott and W.~Schröder and O.~Yu.~Shevchenko and L.~Silva and L.~Sinha and A.~N.~Sissakian and M.~Slunecka and G.~I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.~G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.~V.~Vlassov and L.~Wang and M.~Wilfert and R.~Windmolders and W.~Wiślicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{E}xclusive rho^0 muoproduction on transversely polarised protons and deuterons}, year = {2012}, eprint = {1207.4301}, note = {arXiv:1207.4301v2} }
PDF
The transverse target spin azimuthal asymmetry A_UT in hard exclusive production of rho^0 mesons was measured at COMPASS by scattering 160 GeV/c muons off transversely polarised protons and deuterons. The measured asymmetry is sensitive to the nucleon helicity-flip generalised parton distributions E^q, which are related to the orbital angular momentum of quarks in the nucleon. The Q^2, x_B and p_t^2 dependence of A_UT is presented in a wide kinematic range. Results for deuterons are obtained for the first time. The measured asymmetry is small in the whole kinematic range for both protons and deuterons, which is consistent with the theoretical interpretation that contributions from GPDs E^u and E^d approximately cancel.
Measurement of the Cross Section for High-p_T Hadron Production in Scattering of 160 GeV/c Muons off Nucleons
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, V. Andrieux, A. Austregesilo, B. Badellek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, A. Berlin, J. Bernhard, R. Bertini, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (193)
Jul 10 2012 hep-ex arXiv:1207.2022v2

@misc{1207.2022, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and V.~Andrieux and A.~Austregesilo and B.~Badellek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and A.~Berlin and J.~Bernhard and R.~Bertini and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and M.~Boer and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and M.~Buechele and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and Ch.~Hoeppner and N.~Horikawa and N.~d'Hose and S.~Huber and S.~Ishimoto and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and N.~Kuchinski and F.~Kunne and K.~Kurek and R.P.~Kurjata and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and H.~Matsuda and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and Y.~Miyachi and A.~Morreale and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and C.~Novakova and J.~Novy and W.-D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and M.~Pesek and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and S.~Ramos and G.~Reicherz and E.~Rocco and V.~Rodionov and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and A.~Schmidt and K.~Schmidt and H.~Schmieden and L.~Schmitt and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and S.~Sirtl and M.~Slunecka and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and F.~Thibaud and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and J.~Vondra and L.~Wang and T.~Weisrock and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and N.~Zhuravlev and M.~Ziembicki}, title = {{M}easurement of the {C}ross {S}ection for {H}igh-p_{T} {H}adron {P}roduction in {S}cattering of 160 {G}e{V}/c {M}uons off {N}ucleons}, year = {2012}, eprint = {1207.2022}, note = {arXiv:1207.2022v2} }
PDF
The differential cross section for production of charged hadrons with high transverse momenta in scattering of 160\u2009GeV/$c$ muons off nucleons at low photon virtualities has been measured at the COMPASS experiment at CERN. The results, which cover transverse momenta from 1.1\u2009GeV/$c$ to 3.6\u2009GeV/$c$, are compared to a perturbative Quantum Chromodynamics (pQCD) calculation, in order to evaluate the applicability of pQCD to this process in the kinematic domain of the experiment. The shape of the calculated differential cross section as a function of transverse momentum is found to be in good agreement with the experimental data, but the absolute scale is underestimated by next-to-leading order (NLO) pQCD. The inclusion of all-order resummation of large logarithmic threshold corrections reduces the discrepancy from a factor of three to four to a factor of two. The dependence of the cross section on the pseudo-rapidity and on virtual photon energy fraction is investigated. Finally the dependence on the charge of the hadrons is discussed.
Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, A.A. Antonov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (199)
May 24 2012 hep-ex arXiv:1205.5121v1

@misc{1205.5121, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and A.A.~Antonov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.~Das and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.~Korzenev and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and T.~Negrini and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and W.D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and L.~Schmitt and K.~Schoenning and S.~Schopferer and M.~Schott and W.~Schroeder and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and A.N.~Sissakian and M.~Slunecka and G.I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.V.~Vlassov and L.~Wang and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{E}xperimental investigation of transverse spin asymmetries in muon-p {SIDIS} processes: {C}ollins asymmetries}, year = {2012}, eprint = {1205.5121}, note = {arXiv:1205.5121v1} }
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The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003<x<0.7. These new measurements confirm with higher accuracy previous measurements from the COMPASS and HERMES collaborations, which exhibit a definite effect in the valence quark region. The asymmetries for negative and positive hadrons are similar in magnitude and opposite in sign. They are compatible with model calculations in which the u-quark transversity is opposite in sign and somewhat larger than the d-quark transversity distribution function. The asymmetry is extracted as a function of Bjorken $x$, the relative hadron energy $z$ and the hadron transverse momentum p_T^h. The high statistics and quality of the data also allow for more detailed investigations of the dependence on the kinematic variables. These studies confirm the leading-twist nature of the Collins asymmetry.
Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, A.A. Antonov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (199)
May 24 2012 hep-ex arXiv:1205.5122v1

@misc{1205.5122, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and A.A.~Antonov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and E.~Burtin and L.~Capozza and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.~Das and S.S.~Dasgupta and S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and V.~Jary and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.~Korzenev and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and G.~Meshcheryakov and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and T.~Negrini and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and W.D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and L.~Schmitt and K.~Schoenning and S.~Schopferer and M.~Schott and W.~Schroeder and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and A.N.~Sissakian and M.~Slunecka and G.I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and L.~Steiger and M.~Stolarski and M.~Sulc and R.~Sulej and H.~Suzuki and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.V.~Vlassov and L.~Wang and M.~Wilfert and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{E}xperimental investigation of transverse spin asymmetries in muon-p {SIDIS} processes: {S}ivers asymmetries}, year = {2012}, eprint = {1205.5122}, note = {arXiv:1205.5122v1} }
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The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Sivers asymmetry of the proton has been extracted in the Bjorken x range 0.003<x<0.7. The new measurements have small statistical and systematic uncertainties of a few percent and confirm with considerably better accuracy the previous COMPASS measurement. The Sivers asymmetry is found to be compatible with zero for negative hadrons and positive for positive hadrons, a clear indication of a spin-orbit coupling of quarks in a transversely polarised proton. As compared to measurements at lower energy, a smaller Sivers asymmetry for positive hadrons is found in the region x > 0.03. The asymmetry is different from zero and positive also in the low x region, where sea-quarks dominate. The kinematic dependence of the asymmetry has also been investigated and results are given for various intervals of hadron and virtual photon fractional energy. In contrast to the case of the Collins asymmetry, the results on the Sivers asymmetry suggest a strong dependence on the four-momentum transfer to the nucleon, in agreement with the most recent calculations.
Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering
C. Adolph, M. G. Alekseev, V. Yu. Alexakhin, Yu. Alexandrov, G. D. Alexeev, A. Amoroso, A. A. Antonov, A. Austregesilo, B. Badellek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (196)
Feb 29 2012 hep-ex arXiv:1202.6150v2

@misc{1202.6150, author = {C.~Adolph and M.~G.~Alekseev and V.~Yu.~Alexakhin and Yu.~Alexandrov and G.~D.~Alexeev and A.~Amoroso and A.~A.~Antonov and A.~Austregesilo and B.~Badellek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and E.~Burtin and D.~Chaberny and M.~Chiosso and S.~U.~Chung and A.~Cicuttin and M.~L.~Crespo and S.~Dalla Torre and S.~Das and S.~S.~Dasgupta and O.~Yu.~Denisov and L.~Dhara and S.~V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.~D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger Jr and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.~M.~Friedrich and R.~Garfagnini and F.~Gautheron and O.~P.~Gavrichtchouk and R.~Gazda and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and F.~H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Huber and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.~V.~Khaustov and Yu.~A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.~F.~Konstantinov and A.~Korzenev and A.~M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.~V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.~A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and F.~Massmann and T.~Matsuda and W.~Meyer and T.~Michigami and A.~Mielech and Yu.~V.~Mikhailov and M.~A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and T.~Negrini and F.~Nerling and S.~Neubert and D.~Neyret and V.~I.~Nikolaenko and W.~D.~Nowak and A.~S.~Nunes and A.~G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.~V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.~A.~Polyakov and G.~Pontecorvo and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and N.~S.~Rossiyskaya and D.~I.~Ryabchikov and V.~D.~Samoylenko and A.~Sandacz and M.~G.~Sapozhnikov and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and L.~Schmitt and K.~Schoenning and S.~Schopferer and M.~Schott and O.~Yu.~Shevchenko and L.~Silva and L.~Sinha and A.~N.~Sissakian and M.~Slunecka and G.~I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and R.~Sulej and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.~G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.~V.~Vlassov and A.~Vossen and L.~Wang and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlevd and A.~Zvyagin}, title = {{T}ransverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering}, year = {2012}, eprint = {1202.6150}, howpublished = {Phys. Lett. B 713 (2012) 10-16}, doi = {10.1016/j.physletb.2012.05.015}, note = {arXiv:1202.6150v2} }
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First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities.
Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs
C. Adolph, M.G. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, A.A. Antonov, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, J. Bieling, R. Birsa, J. Bisplinghoff, et al (196)
Feb 21 2012 hep-ex arXiv:1202.4064v1

@misc{1202.4064, author = {C.~Adolph and M.G.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and A.A.~Antonov and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and J.~Bieling and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and C.~Braun and A.~Bravar and A.~Bressan and E.~Burtin and D.~Chaberny and M.~Chiosso and S.U.~Chung and A.~Cicuttin and M.L.~Crespo and S.~Dalla Torre and S.~Das and S.S.~Dasgupta and O.Yu.~Denisov and L.~Dhara and S.V.~Donskov and N.~Doshita and V.~Duic and W.~Duennweber and M.~Dziewiecki and A.~Efremov and C.~Elia and P.D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger jr.~and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.M.~Friedrich and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and R.~Gazda and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabmueller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and T.~Guthoerl and F.~Haas and D.~von Harrach and S.~Hedicke and F.H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Hoeppner and N.~d'Hose and S.~Huber and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and P.~Jasinski and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.H.~Koivuniemi and V.N.~Kolosov and K.~Kondo and K.~Koenigsmann and I.~Konorov and V.F.~Konstantinov and A.~Korzenev and A.M.~Kotzinian and O.~Kouznetsov and M.~Kraemer and Z.V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and J.-M.~Le Goff and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and T.~Matsuda and W.~Meyer and T.~Michigami and Yu.V.~Mikhailov and M.A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and J.P.~Nassalski and F.~Nerling and S.~Neubert and D.~Neyret and V.I.~Nikolaenko and W.D.~Nowak and A.S.~Nunes and A.G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and G.~Pontecorvo and S.L.~Procureur and J.~Pretz and M.~Quaresma and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and N.S.~Rossiyskaya and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlueter and K.~Schmidt and L.~Schmitt and K.~Schoenning and S.~Schopferer and M.~Schott and O.Yu.~Shevchenko and L.~Silva and L.~Sinha and A.N.~Sissakian and M.~Slunecka and G.I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and R.~Sulej and P.~Sznajder and S.~Takekawa and J.~Ter Wolbeek and S.~Tessaro and F.~Tessarotto and L.G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.V.~Vlassov and L.~Wang and R.~Windmolders and W.~Wislicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{L}eading order determination of the gluon polarisation from {DIS} events with high-p_{T} hadron pairs}, year = {2012}, eprint = {1202.4064}, note = {arXiv:1202.4064v1} }
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We present a determination of the gluon polarisation Delta g/g in the nucleon, based on the longitudinal double-spin asymmetry of DIS events with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV/c polarised muon beam scattering off a polarised ^6LiD target. The gluon polarisation is evaluated by a Neural Network approach for three intervals of the gluon momentum fraction x_g covering the range 0.04 < x_g < 0.27. The values obtained at leading order in QCD do not show any significant dependence on x_g. Their average is Delta g/g = 0.125 +/- 0.060 (stat.) +/- 0.063 (syst.) at x_g=0.09 and a scale of mu^2 = 3 (GeV/c)^2.
First Measurement of Chiral Dynamics in \pi^- \gamma -> \pi^- \pi^- \pi^+
M. G. Alekseev, V. Yu. Alexakhin, Yu. Alexandrov, G. D. Alexeev, A. Amoroso, A. Austregesilo, B. Badelek, F. Balestra, J. Barth, G. Baum, Y. Bedfer, J. Bernhard, R. Bertini, M. Bettinelli, K. Bicker, R. Birsa, J. Bisplinghoff, P. Bordalo, F. Bradamante, A. Bravar, et al (186)
Nov 28 2011 hep-ex arXiv:1111.5954v2

@misc{1111.5954, author = {M.~G.~Alekseev and V.~Yu.~Alexakhin and Yu.~Alexandrov and G.~D.~Alexeev and A.~Amoroso and A.~Austregesilo and B.~Badelek and F.~Balestra and J.~Barth and G.~Baum and Y.~Bedfer and J.~Bernhard and R.~Bertini and M.~Bettinelli and K.~Bicker and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and A.~Bravar and A.~Bressan and E.~Burtin and D.~Chaberny and M.~Chiosso and S.~U.~Chung and A.~Cicuttin and M.~L.~Crespo and S.~Dalla Torre and S.~Das and S.~S.~Dasgupta and O.~Yu.~Denisov and L.~Dhara and S.~V.~Donskov and N.~Doshita and V.~Duic and W.~Dünnweber and M.~Dziewiecki and A.~Efremov and P.~D.~Eversheim and W.~Eyrich and M.~Faessler and A.~Ferrero and A.~Filin and M.~Finger and M.~Finger Jr and H.~Fischer and C.~Franco and N.~du Fresne von Hohenesche and J.~M.~Friedrich and R.~Garfagnini and F.~Gautheron and O.~P.~Gavrichtchouk and R.~Gazda and S.~Gerassimov and R.~Geyer and M.~Giorgi and I.~Gnesi and B.~Gobbo and S.~Goertz and S.~Grabm\"uller and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and F.~Haas and D.~von Harrach and T.~Hasegawa and F.~H.~Heinsius and F.~Herrmann and C.~Hess and F.~Hinterberger and N.~Horikawa and Ch.~Höppner and N.~d'Hose and S.~Huber and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and P.~Jasinski and G.~Jegou and R.~Joosten and E.~Kabuss and D.~Kang and B.~Ketzer and G.~V.~Khaustov and Yu.~A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.~H.~Koivuniemi and V.~N.~Kolosov and K.~Kondo and K.~Königsmann and I.~Konorov and V.~F.~Konstantinov and A.~Korzenev and A.~M.~Kotzinian and O.~Kouznetsov and M.~Krämer and Z.~V.~Kroumchtein and F.~Kunne and K.~Kurek and L.~Lauser and A.~A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and A.~Maggiora and A.~Magnon and N.~Makke and G.~K.~Mallot and A.~Mann and C.~Marchand and A.~Martin and J.~Marzec and F.~Massmann and T.~Matsuda and W.~Meyer and T.~Michigami and Yu.~V.~Mikhailov and M.~A.~Moinester and A.~Morreale and A.~Mutter and A.~Nagaytsev and T.~Nagel and F.~Nerling and S.~Neubert and D.~Neyret and V.~I.~Nikolaenko and W.-D.~Nowak and A.~S.~Nunes and A.~G.~Olshevsky and M.~Ostrick and A.~Padee and R.~Panknin and D.~Panzieri and B.~Parsamyan and S.~Paul and E.~Perevalova and G.~Pesaro and D.~V.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.~A.~Polyakov and G.~Pontecorvo and J.~Pretz and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and A.~Richter and E.~Rocco and E.~Rondio and D.~I.~Ryabchikov and V.~D.~Samoylenko and A.~Sandacz and H.~Santos and M.~G.~Sapozhnikov and S.~Sarkar and I.~A.~Savin and G.~Sbrizzai and P.~Schiavon and C.~Schill and T.~Schlüter and L.~Schmitt and S.~Schopferer and W.~Schröder and O.Yu.~Shevchenko and H.-W.~Siebert and L.~Silva and L.~Sinha and A.~N.~Sissakian and M.~Slunecka and G.~I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and M.~Stolarski and M.~Sulc and R.~Sulej and P.~Sznajder and S.~Takekawa and S.~Tessaro and F.~Tessarotto and A.~Teufel and L.~G.~Tkatchev and S.~Uhl and I.~Uman and M.~Vandenbroucke and M.~Virius and N.~V.~Vlassov and R.~Windmolders and W.~Wiślicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and M.~Ziembicki and N.~Zhuravlev and A.~Zvyagin}, title = {{F}irst {M}easurement of {C}hiral {D}ynamics in \pi^- \gamma -> \pi^- \pi^- \pi^+}, year = {2011}, eprint = {1111.5954}, note = {arXiv:1111.5954v2} }
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The COMPASS collaboration at CERN has investigated the \pi^- \gamma -> \pi^- \pi^- \pi^+ reaction at center-of-momentum energy below five pion masses, sqrt(s) < 5 m(\pi), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t' < 0.001 (GeV/c)^2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3\pi-invariant mass m(3\pi) = sqrt(s) were extracted. The absolute cross section was determined in seven bins of $\sqrt{s}$ with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.
DISTO data on Kpp
M. Maggiora, P. Kienle, K. Suzuki, T. Yamazaki, DISTO Collaboration, M. Alexeev, A. Amoroso, F. Balestra, Y. Bedfer, R. Bertini, L. C. Bland, A. Brenschede, F. Brochard, M. P. Bussa, S. Choi, M. L. Colantoni, R. Dressler, M. Dzemidzic, J. Cl. Faivre, L. Ferrero, et al (18)
Dec 29 2009 hep-ex arXiv:0912.5116v1

@misc{0912.5116, author = {M.~Maggiora and P.~Kienle and K.~Suzuki and T.~Yamazaki and DISTO Collaboration and M.~Alexeev and A.~Amoroso and F.~Balestra and Y.~Bedfer and R.~Bertini and L.~C.~Bland and A.~Brenschede and F.~Brochard and M.~P.~Bussa and S.~Choi and M.~L.~Colantoni and R.~Dressler and M.~Dzemidzic and J.~Cl.~Faivre and L.~Ferrero and J.~Foryciarz and I.~Fröhlich and V.~Frolov and R.~Garfagnini and A.~Grasso and S.~Heinz and W.~W.~Jacobs and W.~Kühn and A.~Maggiora and D.~Panzieri and S.~Sosio and H.~W.~Pfaff and G.~Pontecorvo and A.~Popov and J.~Ritman and P.~Salabura and V.~Tchalyshev and S.~E.~Vigdor}, title = {{DISTO} data on {K}pp}, year = {2009}, eprint = {0912.5116}, howpublished = {Nucl.Phys.A835:43-50,2010}, doi = {10.1016/j.nuclphysa.2010.01.173}, note = {arXiv:0912.5116v1} }
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The data from the DISTO Collaboration on the exclusive pp -> p K+ Lambda production acquired at T_p = 2.85 GeV have been re-analysed in order to search for a deeply bound K- pp (= X) state, to be formed in the binary process pp -> K+ X. The preliminary spectra of the DeltaM_K+ missing-mass and of the M_p Lambda invariant-mass show, for large transverse-momenta of protons and kaons, a distinct broad peak with a mass M_X = 2265 +- 2 MeV/c^2 and a width Gamma_X = 118 +- 8 MeV/c^2.
Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets
PANDA Collaboration, W. Erni, I. Keshelashvili, B. Krusche, M. Steinacher, Y. Heng, Z. Liu, H. Liu, X. Shen, O. Wang, H. Xu, J. Becker, F. Feldbauer, F.-H. Heinsius, T. Held, H. Koch, B. Kopf, M. Pelizaeus, T. Schroeder, M. Steinke, et al (392)
Jul 02 2009 physics.ins-det hep-ex arXiv:0907.0169v1

@misc{0907.0169, author = {PANDA Collaboration and W.~Erni and I.~Keshelashvili and B.~Krusche and M.~Steinacher and Y.~Heng and Z.~Liu and H.~Liu and X.~Shen and O.~Wang and H.~Xu and J.~Becker and F.~Feldbauer and F.-H.~Heinsius and T.~Held and H.~Koch and B.~Kopf and M.~Pelizaeus and T.~Schroeder and M.~Steinke and U.~Wiedner and J.~Zhong and A.~Bianconi and M.~Bragadireanu and D.~Pantea and A.~Tudorache and V.~Tudorache and M.~De Napoli and F.~Giacoppo and G.~Raciti and E.~Rapisarda and C.~Sfienti and E.~Bialkowski and A.~Budzanowski and B.~Czech and M.~Kistryn and S.~Kliczewski and A.~Kozela and P.~Kulessa and K.~Pysz and W.~Schaefer and R.~Siudak and A.~Szczurek and W.~Czy.zycki and M.~Domagala and M.~Hawryluk and E.~Lisowski and F.~Lisowski and L.~Wojnar and D.~Gil and P.~Hawranek and B.~Kamys and St.~Kistryn and K.~Korcyl and W.~Krzemien and A.~Magiera and P.~Moskal and Z.~Rudy and P.~Salabura and J.~Smyrski and A.~Wronska and M.~Al-Turany and I.~Augustin and H.~Deppe and H.~Flemming and J.~Gerl and K.~Goetzen and R.~Hohler and D.~Lehmann and B.~Lewandowski and J.~Luehning and F.~Maas and D.~Mishra and H.~Orth and K.~Peters and T.~Saito and G.~Schepers and C.J.~Schmidt and L.~Schmitt and C.~Schwarz and B.~Voss and P.~Wieczorek and A.~Wilms and K.-T.~Brinkmann and H.~Freiesleben and R.~Jaekel and R.~Kliemt and T.~Wuerschig and H.-G.~Zaunick and V.M.~Abazov and G.~Alexeev and A.~Arefiev and V.I.~Astakhov and M.Yu.~Barabanov and B.V.~Batyunya and Yu.I.~Davydov and V.Kh.~Dodokhov and A.A.~Efremov and A.G.~Fedunov and A.A.~Feshchenko and A.S.~Galoyan and S.~Grigoryan and A.~Karmokov and E.K.~Koshurnikov and V.Ch.~Kudaev and V.I.~Lobanov and Yu.Yu.~Lobanov and A.F.~Makarov and L.V.~Malinina and V.L.~Malyshev and G.A.~Mustafaev and A.~Olshevski and M.A..~Pasyuk and E.A.~Perevalova and A.A.~Piskun and T.A.~Pocheptsov and G.~Pontecorvo and V.K.~Rodionov and Yu.N.~Rogov and R.A.~Salmin and A.G.~Samartsev and M.G.~Sapozhnikov and A.~Shabratova and G.S.~Shabratova and A.N.~Skachkova and N.B.~Skachkov and E.A.~Strokovsky and M.K.~Suleimanov and R.Sh.~Teshev and V.V.~Tokmenin and V.V.~Uzhinsky and A.S.~Vodopianov and S.A.~Zaporozhets and N.I.~Zhuravlev and A.G.~Zorin and D.~Branford and K.~Foehl and D.~Glazier and D.~Watts and P.~Woods and W.~Eyrich and A.~Lehmann and A.~Teufel and S.~Dobbs and Z.~Metreveli and K.~Seth and B.~Tann and A.~Tomaradze and D.~Bettoni and V.~Carassiti and A.~Cecchi and P.~Dalpiaz and E.~Fioravanti and I.~Garzia and M.~Negrini and M.~Savri`e and G.~Stancari and B.~Dulach and P.~Gianotti and C.~Guaraldo and V.~Lucherini and E.~Pace and A.~Bersani and M.~Macri and M.~Marinelli and R.F.~Parodi and I.~Brodski and W.~Doering and P.~Drexler and M.~Dueren and Z.~Gagyi-Palffy and A.~Hayrapetyan and M.~Kotulla and W.~Kuehn and S.~Lange and M.~Liu and V.~Metag and M.~Nanova and R.~Novotny and C.~Salz and J.~Schneider and P.~Schoenmeier and R.~Schubert and S.~Spataro and H.~Stenzel and C.~Strackbein and M.~Thiel and U.~Thoering and S.~Yang and T.~Clarkson and E.~Cowie and E.~Downie and G.~Hill and M.~Hoek and D.~Ireland and R.~Kaiser and T.~Keri and I.~Lehmann and K.~Livingston and S.~Lumsden and D.~MacGregor and B.~McKinnon and M.~Murray and D.~Protopopescu and G.~Rosner and B.~Seitz and G.~Yang and M.~Babai and A.K.~Biegun and A.~Bubak and E.~Guliyev and V.S.~Jothi and M.~Kavatsyuk and H.~Loehner and J.~Messchendorp and H.~Smit and J.C.~van der Weele and F.~Garcia and D.-O.~Riska and M.~Buescher and R.~Dosdall and R.~Dzhygadlo and A.~Gillitzer and D.~Grunwald and V.~Jha and G.~Kemmerling and H.~Kleines and A.~Lehrach and R.~Maier and M.~Mertens and H.~Ohm and D.~Prasuhn and T.~Randriamalala and J.~Ritman and M.~Roeder and T.~Stockmanns and P.~Wintz and P.~Wuestner and J.~Kisiel and S.~Li and Z.~Li and Z.~Sun and H.~Xu and S.~Fissum and K.~Hansen and L.~Isaksson and M.~Lundin and B.~Schroeder and P.~Achenbach and M.C.~Mora Espi and J.~Pochodzalla and S.~Sanchez and A.~Sanchez-Lorente and V.I.~Dormenev and A.A.~Fedorov and M.V.~Korzhik and O.V.~Missevitch and V.~Balanutsa and V.~Chernetsky and A.~Demekhin and A.~Dolgolenko and P.~Fedorets and A.~Gerasimov and V.~Goryachev and A.~Boukharov and O.~Malyshev and I.~Marishev and A.~Semenov and C.~Hoeppner and B.~Ketzer and I.~Konorov and A.~Mann and S.~Neubert and S.~Paul and Q.~Weitzel and A.~Khoukaz and T.~Rausmann and A.~Taeschner and J.~Wessels and R.~Varma and E.~Baldin and K.~Kotov and S.~Peleganchuk and Yu.~Tikhonov and J.~Boucher and T.~Hennino and R.~Kunne and S.~Ong and J.~Pouthas and B.~Ramstein and P.~Rosier and M.~Sudol and J.~Van de Wiele and T.~Zerguerras and K.~Dmowski and R.~Korzeniewski and D.~Przemyslaw and B.~Slowinski and G.~Boca and A.~Braghieri and S.~Costanza and A.~Fontana and P.~Genova and L.~Lavezzi and P.~Montagna and A.~Rotondi and N.I.~Belikov and A.M.~Davidenko and A.A.~Derevschikov and Y.M.~Goncharenko and V.N.~Grishin and V.A.~Kachanov and D.A.~Konstantinov and V.A.~Kormilitsin and V.I.~Kravtsov and Y.A.~Matulenko and Y.M.~Melnik and A.P.~Meschanin and N.G.~Minaev and V.V.~Mochalov and D.A.~Morozov and L.V.~Nogach and S.B.~Nurushev and A.V.~Ryazantsev and P.A.~Semenov and L.F.~Soloviev and A.V.~Uzunian and A.N.~Vasiliev and A.E.~Yakutin and T.~Baeck and B.~Cederwall and C.~Bargholtz and L.~Geren and P.E.~Tegner and S.~Belostotski and G.~Gavrilov and A.~Itzotov and A.~Kisselev and P.~Kravchenko and S.~Manaenkov and O.~Miklukho and Y.~Naryshkin and D.~Veretennikov and V.~Vikhrov and A.~Zhadanov and L.~Fava and D.~Panzieri and D.~Alberto and A.~Amoroso and E.~Botta and T.~Bressani and S.~Bufalino and M.P.~Bussa and L.~Busso and F.~De Mori and M.~Destefanis and L.~Ferrero and A.~Grasso and M.~Greco and T.~Kugathasan and M.~Maggiora and S.~Marcello and G.~Serbanut and S.~Sosio and R.~Bertini and D.~Calvo and S.~Coli and P.~De Remigis and A.~Feliciello and A.~Filippi and G.~Giraudo and G.~Mazza and A.~Rivetti and K.~Szymanska and F.~Tosello and R.~Wheadon and O.~Morra and M.~Agnello and F.~Iazzi and K.~Szymanska and R.~Birsa and F.~Bradamante and A.~Bressan and A.~Martin and H.~Clement and C.~Ekstroem and H.~Calen and S.~Grape and B.~Hoeistad and T.~Johansson and A.~Kupsc and P.~Marciniewski and E.~Thome and J.~Zlomanczuk and J.~Diaz and A.~Ortiz and S.~Borsuk and A.~Chlopik and Z.~Guzik and J.~Kopec and T.~Kozlowski and D.~Melnychuk and M.~Plominski and J.~Szewinski and K.~Traczyk and B.~Zwieglinski and P.~Buehler and A.~Gruber and P.~Kienle and J.~Marton and E.~Widmann and J.~Zmeskal}, title = {{T}echnical {D}esign {R}eport for the {PANDA} {S}olenoid and {D}ipole {S}pectrometer {M}agnets}, year = {2009}, eprint = {0907.0169}, note = {arXiv:0907.0169v1} }
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This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible modifications arising during this process.
Physics Performance Report for PANDA: Strong Interaction Studies with Antiprotons
PANDA Collaboration, W. Erni, I. Keshelashvili, B. Krusche, M. Steinacher, Y. Heng, Z. Liu, H. Liu, X. Shen, O. Wang, H. Xu, J. Becker, F. Feldbauer, F.-H. Heinsius, T. Held, H. Koch, B. Kopf, M. Pelizaeus, T. Schroeder, M. Steinke, et al (396)
Mar 24 2009 hep-ex arXiv:0903.3905v1

@misc{0903.3905, author = {PANDA Collaboration and W.~Erni and I.~Keshelashvili and B.~Krusche and M.~Steinacher and Y.~Heng and Z.~Liu and H.~Liu and X.~Shen and O.~Wang and H.~Xu and J.~Becker and F.~Feldbauer and F.-H.~Heinsius and T.~Held and H.~Koch and B.~Kopf and M.~Pelizaeus and T.~Schroeder and M.~Steinke and U.~Wiedner and J.~Zhong and A.~Bianconi and M.~Bragadireanu and D.~Pantea and A.~Tudorache and V.~Tudorache and M.~De Napoli and F.~Giacoppo and G.~Raciti and E.~Rapisarda and C.~Sfienti and E.~Bialkowski and A.~Budzanowski and B.~Czech and M.~Kistryn and S.~Kliczewski and A.~Kozela and P.~Kulessa and K.~Pysz and W.~Schaefer and R.~Siudak and A.~Szczurek and W.~Czy.zycki and M.~Domagala and M.~Hawryluk and E.~Lisowski and F.~Lisowski and L.~Wojnar and D.~Gil and P.~Hawranek and B.~Kamys and St.~Kistryn and K.~Korcyl and W.~Krzemien and A.~Magiera and P.~Moskal and Z.~Rudy and P.~Salabura and J.~Smyrski and A.~Wronska and M.~Al-Turany and I.~Augustin and H.~Deppe and H.~Flemming and J.~Gerl and K.~Goetzen and R.~Hohler and D.~Lehmann and B.~Lewandowski and J.~Luehning and F.~Maas and D.~Mishra and H.~Orth and K.~Peters and T.~Saito and G.~Schepers and C.J.~Schmidt and L.~Schmitt and C.~Schwarz and B.~Voss and P.~Wieczorek and A.~Wilms and K.-T.~Brinkmann and H.~Freiesleben and R.~Jaekel and R.~Kliemt and T.~Wuerschig and H.-G.~Zaunick and V.M.~Abazov and G.~Alexeev and A.~Arefiev and V.I.~Astakhov and M.Yu.~Barabanov and B.V.~Batyunya and Yu.I.~Davydov and V.Kh.~Dodokhov and A.A.~Efremov and A.G.~Fedunov and A.A.~Feshchenko and A.S.~Galoyan and S.~Grigoryan and A.~Karmokov and E.K.~Koshurnikov and V.Ch.~Kudaev and V.I.~Lobanov and Yu.Yu.~Lobanov and A.F.~Makarov and L.V.~Malinina and V.L.~Malyshev and G.A.~Mustafaev and A.~Olshevski and M.A..~Pasyuk and E.A.~Perevalova and A.A.~Piskun and T.A.~Pocheptsov and G.~Pontecorvo and V.K.~Rodionov and Yu.N.~Rogov and R.A.~Salmin and A.G.~Samartsev and M.G.~Sapozhnikov and A.~Shabratova and G.S.~Shabratova and A.N.~Skachkova and N.B.~Skachkov and E.A.~Strokovsky and M.K.~Suleimanov and R.Sh.~Teshev and V.V.~Tokmenin and V.V.~Uzhinsky and A.S.~Vodopianov and S.A.~Zaporozhets and N.I.~Zhuravlev and A.G.~Zorin and D.~Branford and K.~Foehl and D.~Glazier and D.~Watts and P.~Woods and W.~Eyrich and A.~Lehmann and A.~Teufel and S.~Dobbs and Z.~Metreveli and K.~Seth and B.~Tann and A.~Tomaradze and D.~Bettoni and V.~Carassiti and A.~Cecchi and P.~Dalpiaz and E.~Fioravanti and I.~Garzia and M.~Negrini and M.~Savri`e and G.~Stancari and B.~Dulach and P.~Gianotti and C.~Guaraldo and V.~Lucherini and E.~Pace and A.~Bersani and M.~Macri and M.~Marinelli and R.F.~Parodi and I.~Brodski and W.~Doering and P.~Drexler and M.~Dueren and Z.~Gagyi-Palffy and A.~Hayrapetyan and M.~Kotulla and W.~Kuehn and S.~Lange and M.~Liu and V.~Metag and M.~Nanova and R.~Novotny and C.~Salz and J.~Schneider and P.~Schoenmeier and R.~Schubert and S.~Spataro and H.~Stenzel and C.~Strackbein and M.~Thiel and U.~Thoering and S.~Yang and T.~Clarkson and E.~Cowie and E.~Downie and G.~Hill and M.~Hoek and D.~Ireland and R.~Kaiser and T.~Keri and I.~Lehmann and K.~Livingston and S.~Lumsden and D.~MacGregor and B.~McKinnon and M.~Murray and D.~Protopopescu and G.~Rosner and B.~Seitz and G.~Yang and M.~Babai and A.K.~Biegun and A.~Bubak and E.~Guliyev and V.S.~Jothi and M.~Kavatsyuk and H.~Loehner and J.~Messchendorp and H.~Smit and J.C.~van der Weele and F.~Garcia and D.-O.~Riska and M.~Buescher and R.~Dosdall and R.~Dzhygadlo and A.~Gillitzer and D.~Grunwald and V.~Jha and G.~Kemmerling and H.~Kleines and A.~Lehrach and R.~Maier and M.~Mertens and H.~Ohm and D.~Prasuhn and T.~Randriamalala and J.~Ritman and M.~Roeder and T.~Stockmanns and P.~Wintz and P.~Wuestner and J.~Kisiel and S.~Li and Z.~Li and Z.~Sun and H.~Xu and S.~Fissum and K.~Hansen and L.~Isaksson and M.~Lundin and B.~Schroeder and P.~Achenbach and M.C.~Mora Espi and J.~Pochodzalla and S.~Sanchez and A.~Sanchez-Lorente and V.I.~Dormenev and A.A.~Fedorov and M.V.~Korzhik and O.V.~Missevitch and V.~Balanutsa and V.~Chernetsky and A.~Demekhin and A.~Dolgolenko and P.~Fedorets and A.~Gerasimov and V.~Goryachev and A.~Boukharov and O.~Malyshev and I.~Marishev and A.~Semenov and C.~Hoeppner and B.~Ketzer and I.~Konorov and A.~Mann and S.~Neubert and S.~Paul and Q.~Weitzel and A.~Khoukaz and T.~Rausmann and A.~Taeschner and J.~Wessels and R.~Varma and E.~Baldin and K.~Kotov and S.~Peleganchuk and Yu.~Tikhonov and J.~Boucher and T.~Hennino and R.~Kunne and S.~Ong and J.~Pouthas and B.~Ramstein and P.~Rosier and M.~Sudol and J.~Van de Wiele and T.~Zerguerras and K.~Dmowski and R.~Korzeniewski and D.~Przemyslaw and B.~Slowinski and G.~Boca and A.~Braghieri and S.~Costanza and A.~Fontana and P.~Genova and L.~Lavezzi and P.~Montagna and A.~Rotondi and N.I.~Belikov and A.M.~Davidenko and A.A.~Derevschikov and Y.M.~Goncharenko and V.N.~Grishin and V.A.~Kachanov and D.A.~Konstantinov and V.A.~Kormilitsin and V.I.~Kravtsov and Y.A.~Matulenko and Y.M.~Melnik and A.P.~Meschanin and N.G.~Minaev and V.V.~Mochalov and D.A.~Morozov and L.V.~Nogach and S.B.~Nurushev and A.V.~Ryazantsev and P.A.~Semenov and L.F.~Soloviev and A.V.~Uzunian and A.N.~Vasiliev and A.E.~Yakutin and T.~Baeck and B.~Cederwall and C.~Bargholtz and L.~Geren and P.E.~Tegner and S.~Belostotski and G.~Gavrilov and A.~Itzotov and A.~Kisselev and P.~Kravchenko and S.~Manaenkov and O.~Miklukho and Y.~Naryshkin and D.~Veretennikov and V.~Vikhrov and A.~Zhadanov and L.~Fava and D.~Panzieri and D.~Alberto and A.~Amoroso and E.~Botta and T.~Bressani and S.~Bufalino and M.P.~Bussa and L.~Busso and F.~De Mori and M.~Destefanis and L.~Ferrero and A.~Grasso and M.~Greco and T.~Kugathasan and M.~Maggiora and S.~Marcello and G.~Serbanut and S.~Sosio and R.~Bertini and D.~Calvo and S.~Coli and P.~De Remigis and A.~Feliciello and A.~Filippi and G.~Giraudo and G.~Mazza and A.~Rivetti and K.~Szymanska and F.~Tosello and R.~Wheadon and O.~Morra and M.~Agnello and F.~Iazzi and K.~Szymanska and R.~Birsa and F.~Bradamante and A.~Bressan and A.~Martin and H.~Clement and C.~Ekstroem and H.~Calen and S.~Grape and B.~Hoeistad and T.~Johansson and A.~Kupsc and P.~Marciniewski and E.~Thome and J.~Zlomanczuk and J.~Diaz and A.~Ortiz and S.~Borsuk and A.~Chlopik and Z.~Guzik and J.~Kopec and T.~Kozlowski and D.~Melnychuk and M.~Plominski and J.~Szewinski and K.~Traczyk and B.~Zwieglinski and P.~Buehler and A.~Gruber and P.~Kienle and J.~Marton and E.~Widmann and J.~Zmeskal and M.F.M.~Lutz and B.~Pire and O.~Scholten and R.~Timmermans}, title = {{P}hysics {P}erformance {R}eport for {PANDA}: {S}trong {I}nteraction {S}tudies with {A}ntiprotons}, year = {2009}, eprint = {0903.3905}, note = {arXiv:0903.3905v1} }
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To study fundamental questions of hadron and nuclear physics in interactions of antiprotons with nucleons and nuclei, the universal PANDA detector will be built. Gluonic excitations, the physics of strange and charm quarks and nucleon structure studies will be performed with unprecedented accuracy thereby allowing high-precision tests of the strong interaction. The proposed PANDA detector is a state-of-the art internal target detector at the HESR at FAIR allowing the detection and identification of neutral and charged particles generated within the relevant angular and energy range. This report presents a summary of the physics accessible at PANDA and what performance can be expected.
Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)
PANDA Collaboration, W. Erni, I. Keshelashvili, B. Krusche, M. Steinacher, Y. Heng, Z. Liu, H. Liu, X. Shen, O. Wang, H. Xu, J. Becker, F. Feldbauer, F.-H. Heinsius, T. Held, H. Koch, B. Kopf, M. Pelizaeus, T. Schroeder, M. Steinke, et al (392)
Oct 08 2008 physics.ins-det hep-ex arXiv:0810.1216v1

@misc{0810.1216, author = {PANDA Collaboration and W.~Erni and I.~Keshelashvili and B.~Krusche and M.~Steinacher and Y.~Heng and Z.~Liu and H.~Liu and X.~Shen and O.~Wang and H.~Xu and J.~Becker and F.~Feldbauer and F.-H.~Heinsius and T.~Held and H.~Koch and B.~Kopf and M.~Pelizaeus and T.~Schroeder and M.~Steinke and U.~Wiedner and J.~Zhong and A.~Bianconi and M.~Bragadireanu and D.~Pantea and A.~Tudorache and V.~Tudorache and M.~De Napoli and F.~Giacoppo and G.~Raciti and E.~Rapisarda and C.~Sfienti and E.~Bialkowski and A.~Budzanowski and B.~Czech and M.~Kistryn and S.~Kliczewski and A.~Kozela and P.~Kulessa and K.~Pysz and W.~Schaefer and R.~Siudak and A.~Szczurek and W.~Czy.zycki and M.~Domagala and M.~Hawryluk and E.~Lisowski and F.~Lisowski and L.~Wojnar and D.~Gil and P.~Hawranek and B.~Kamys and St.~Kistryn and K.~Korcyl and W.~Krzemien and A.~Magiera and P.~Moskal and Z.~Rudy and P.~Salabura and J.~Smyrski and A.~Wronska and M.~Al-Turany and I.~Augustin and H.~Deppe and H.~Flemming and J.~Gerl and K.~Goetzen and R.~Hohler and D.~Lehmann and B.~Lewandowski and J.~Luehning and F.~Maas and D.~Mishra and H.~Orth and K.~Peters and T.~Saito and G.~Schepers and C.J.~Schmidt and L.~Schmitt and C.~Schwarz and B.~Voss and P.~Wieczorek and A.~Wilms and K.-T.~Brinkmann and H.~Freiesleben and R.~Jaekel and R.~Kliemt and T.~Wuerschig and H.-G.~Zaunick and V.M.~Abazov and G.~Alexeev and A.~Arefiev and V.I.~Astakhov and M.Yu.~Barabanov and B.V.~Batyunya and Yu.I.~Davydov and V.Kh.~Dodokhov and A.A.~Efremov and A.G.~Fedunov and A.A.~Feshchenko and A.S.~Galoyan and S.~Grigoryan and A.~Karmokov and E.K.~Koshurnikov and V.Ch.~Kudaev and V.I.~Lobanov and Yu.Yu.~Lobanov and A.F.~Makarov and L.V.~Malinina and V.L.~Malyshev and G.A.~Mustafaev and A.~Olshevski and M.A..~Pasyuk and E.A.~Perevalova and A.A.~Piskun and T.A.~Pocheptsov and G.~Pontecorvo and V.K.~Rodionov and Yu.N.~Rogov and R.A.~Salmin and A.G.~Samartsev and M.G.~Sapozhnikov and A.~Shabratova and G.S.~Shabratova and A.N.~Skachkova and N.B.~Skachkov and E.A.~Strokovsky and M.K.~Suleimanov and R.Sh.~Teshev and V.V.~Tokmenin and V.V.~Uzhinsky and A.S.~Vodopianov and S.A.~Zaporozhets and N.I.~Zhuravlev and A.G.~Zorin and D.~Branford and K.~Foehl and D.~Glazier and D.~Watts and P.~Woods and W.~Eyrich and A.~Lehmann and A.~Teufel and S.~Dobbs and Z.~Metreveli and K.~Seth and B.~Tann and A.~Tomaradze and D.~Bettoni and V.~Carassiti and A.~Cecchi and P.~Dalpiaz and E.~Fioravanti and I.~Garzia and M.~Negrini and M.~Savri`e and G.~Stancari and B.~Dulach and P.~Gianotti and C.~Guaraldo and V.~Lucherini and E.~Pace and A.~Bersani and M.~Macri and M.~Marinelli and R.F.~Parodi and I.~Brodski and W.~Doering and P.~Drexler and M.~Dueren and Z.~Gagyi-Palffy and A.~Hayrapetyan and M.~Kotulla and W.~Kuehn and S.~Lange and M.~Liu and V.~Metag and M.~Nanova and R.~Novotny and C.~Salz and J.~Schneider and P.~Schoenmeier and R.~Schubert and S.~Spataro and H.~Stenzel and C.~Strackbein and M.~Thiel and U.~Thoering and S.~Yang and T.~Clarkson and E.~Cowie and E.~Downie and G.~Hill and M.~Hoek and D.~Ireland and R.~Kaiser and T.~Keri and I.~Lehmann and K.~Livingston and S.~Lumsden and D.~MacGregor and B.~McKinnon and M.~Murray and D.~Protopopescu and G.~Rosner and B.~Seitz and G.~Yang and M.~Babai and A.K.~Biegun and A.~Bubak and E.~Guliyev and V.S.~Jothi and M.~Kavatsyuk and H.~Loehner and J.~Messchendorp and H.~Smit and J.C.~van der Weele and F.~Garcia and D.-O.~Riska and M.~Buescher and R.~Dosdall and R.~Dzhygadlo and A.~Gillitzer and D.~Grunwald and V.~Jha and G.~Kemmerling and H.~Kleines and A.~Lehrach and R.~Maier and M.~Mertens and H.~Ohm and D.~Prasuhn and T.~Randriamalala and J.~Ritman and M.~Roeder and T.~Stockmanns and P.~Wintz and P.~Wuestner and J.~Kisiel and S.~Li and Z.~Li and Z.~Sun and H.~Xu and S.~Fissum and K.~Hansen and L.~Isaksson and M.~Lundin and B.~Schroeder and P.~Achenbach and M.C.~Mora Espi and J.~Pochodzalla and S.~Sanchez and A.~Sanchez-Lorente and V.I.~Dormenev and A.A.~Fedorov and M.V.~Korzhik and O.V.~Missevitch and V.~Balanutsa and V.~Chernetsky and A.~Demekhin and A.~Dolgolenko and P.~Fedorets and A.~Gerasimov and V.~Goryachev and A.~Boukharov and O.~Malyshev and I.~Marishev and A.~Semenov and C.~Hoeppner and B.~Ketzer and I.~Konorov and A.~Mann and S.~Neubert and S.~Paul and Q.~Weitzel and A.~Khoukaz and T.~Rausmann and A.~Taeschner and J.~Wessels and R.~Varma and E.~Baldin and K.~Kotov and S.~Peleganchuk and Yu.~Tikhonov and J.~Boucher and T.~Hennino and R.~Kunne and S.~Ong and J.~Pouthas and B.~Ramstein and P.~Rosier and M.~Sudol and J.~Van de Wiele and T.~Zerguerras and K.~Dmowski and R.~Korzeniewski and D.~Przemyslaw and B.~Slowinski and G.~Boca and A.~Braghieri and S.~Costanza and A.~Fontana and P.~Genova and L.~Lavezzi and P.~Montagna and A.~Rotondi and N.I.~Belikov and A.M.~Davidenko and A.A.~Derevschikov and Y.M.~Goncharenko and V.N.~Grishin and V.A.~Kachanov and D.A.~Konstantinov and V.A.~Kormilitsin and V.I.~Kravtsov and Y.A.~Matulenko and Y.M.~Melnik and A.P.~Meschanin and N.G.~Minaev and V.V.~Mochalov and D.A.~Morozov and L.V.~Nogach and S.B.~Nurushev and A.V.~Ryazantsev and P.A.~Semenov and L.F.~Soloviev and A.V.~Uzunian and A.N.~Vasiliev and A.E.~Yakutin and T.~Baeck and B.~Cederwall and C.~Bargholtz and L.~Geren and P.E.~Tegner and S.~Belostotski and G.~Gavrilov and A.~Itzotov and A.~Kisselev and P.~Kravchenko and S.~Manaenkov and O.~Miklukho and Y.~Naryshkin and D.~Veretennikov and V.~Vikhrov and A.~Zhadanov and L.~Fava and D.~Panzieri and D.~Alberto and A.~Amoroso and E.~Botta and T.~Bressani and S.~Bufalino and M.P.~Bussa and L.~Busso and F.~De Mori and M.~Destefanis and L.~Ferrero and A.~Grasso and M.~Greco and T.~Kugathasan and M.~Maggiora and S.~Marcello and G.~Serbanut and S.~Sosio and R.~Bertini and D.~Calvo and S.~Coli and P.~De Remigis and A.~Feliciello and A.~Filippi and G.~Giraudo and G.~Mazza and A.~Rivetti and K.~Szymanska and F.~Tosello and R.~Wheadon and O.~Morra and M.~Agnello and F.~Iazzi and K.~Szymanska and R.~Birsa and F.~Bradamante and A.~Bressan and A.~Martin and H.~Clement and C.~Ekstroem and H.~Calen and S.~Grape and B.~Hoeistad and T.~Johansson and A.~Kupsc and P.~Marciniewski and E.~Thome and J.~Zlomanczuk and J.~Diaz and A.~Ortiz and S.~Borsuk and A.~Chlopik and Z.~Guzik and J.~Kopec and T.~Kozlowski and D.~Melnychuk and M.~Plominski and J.~Szewinski and K.~Traczyk and B.~Zwieglinski and P.~Buehler and A.~Gruber and P.~Kienle and J.~Marton and E.~Widmann and J.~Zmeskal}, title = {{T}echnical {D}esign {R}eport for {PANDA} {E}lectromagnetic {C}alorimeter ({EMC})}, year = {2008}, eprint = {0810.1216}, note = {arXiv:0810.1216v1} }
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This document presents the technical layout and the envisaged performance of the Electromagnetic Calorimeter (EMC) for the PANDA target spectrometer. The EMC has been designed to meet the physics goals of the PANDA experiment, which is being developed for the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, Germany. The performance figures are based on extensive prototype tests and radiation hardness studies. The document shows that the EMC is ready for construction up to the front-end electronics interface.
Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS
COMPASS Collaboration, M. Alekseev, V.Yu. Alexakhin, Yu. Alexandrov, G.D. Alexeev, A. Amoroso, A. Arbuzov, B. Badełek, F. Balestra, J. Ball, J. Barth, G. Baum, Y. Bedfer, C. Bernet, R. Bertini, M. Bettinelli, R. Birsa, J. Bisplinghoff, P. Bordalo, F. Bradamante, et al (222)
Feb 18 2008 hep-ex arXiv:0802.2160v2

@misc{0802.2160, author = {COMPASS Collaboration and M.~Alekseev and V.Yu.~Alexakhin and Yu.~Alexandrov and G.D.~Alexeev and A.~Amoroso and A.~Arbuzov and B.~Badełek and F.~Balestra and J.~Ball and J.~Barth and G.~Baum and Y.~Bedfer and C.~Bernet and R.~Bertini and M.~Bettinelli and R.~Birsa and J.~Bisplinghoff and P.~Bordalo and F.~Bradamante and A.~Bravar and A.~Bressan and G.~Brona and E.~Burtin and M.P.~Bussa and A.~Chapiro and M.~Chiosso and A.~Cicuttin and M.~Colantoni and S.~Costa and M.L.~Crespo and S.~Dalla Torre and T.~Dafni and S.~Das and S.S.~Dasgupta and R.~De Masi and N.~Dedek and O.Yu.~Denisov and L.~Dhara and V.~Diaz and A.M.~Dinkelbach and S.V.~Donskov and V.A.~Dorofeev and N.~Doshita and V.~Duic and W.~Dünnweber and P.D.~Eversheim and A.V.~Efremov and W.~Eyrich and M.~Faessler and V.~Falaleev and A.~Ferrero and L.~Ferrero and M.~Finger and M.~Finger Jr.~and H.~Fischer and C.~Franco and J.~Franz and J.M.~Friedrich and V.~Frolov and R.~Garfagnini and F.~Gautheron and O.P.~Gavrichtchouk and R.~Gazda and S.~Gerassimov and R.~Geyer and M.~Giorgi and B.~Gobbo and S.~Goertz and A.M.~Gorin and S.~Grabmüller and O.A.~Grajek and A.~Grasso and B.~Grube and R.~Gushterski and A.~Guskov and F.~Haas and J.~Hannappel and D.~von Harrach and T.~Hasegawa and J.~Heckmann and S.~Hedicke and F.H.~Heinsius and R.~Hermann and C.~Heß and F.~Hinterberger and M.~von Hodenberg and N.~Horikawa and S.~Horikawa and N.~d'Hose and C.~Ilgner and A.I.~Ioukaev and S.~Ishimoto and O.~Ivanov and Yu.~Ivanshin and T.~Iwata and R.~Jahn and A.~Janata and P.~Jasinski and R.~Joosten and N.I.~Jouravlev and E.~Kabuß and D.~Kang and B.~Ketzer and G.V.~Khaustov and Yu.A.~Khokhlov and Yu.~Kisselev and F.~Klein and K.~Klimaszewski and S.~Koblitz and J.H.~Koivuniemi and V.N.~Kolosov and E.V.~Komissarov and K.~Kondo and K.~Königsmann and I.~Konorov and V.F.~Konstantinov and A.S.~Korentchenko and A.~Korzenev and A.M.~Kotzinian and N.A.~Koutchinski and O.~Kouznetsov and A.~Kral and N.P.~Kravchuk and Z.V.~Kroumchtein and R.~Kuhn and F.~Kunne and K.~Kurek and M.E.~Ladygin and M.~Lamanna and J.M.~Le Goff and A.A.~Lednev and A.~Lehmann and S.~Levorato and J.~Lichtenstadt and T.~Liska and I.~Ludwig and A.~Maggiora and M.~Maggiora and A.~Magnon and G.K.~Mallot and A.~Mann and C.~Marchand and J.~Marroncle and A.~Martin and J.~Marzec and F.~Massmann and T.~Matsuda and A.N.~Maximov and W.~Meyer and A.~Mielech and Yu.V.~Mikhailov and M.A.~Moinester and A.~Mutter and A.~Nagaytsev and T.~Nagel and O.~Nähle and J.~Nassalski and S.~Neliba and F.~Nerling and S.~Neubert and D.P.~Neyret and V.I.~Nikolaenko and K.~Nikolaev and A.G.~Olshevsky and M.~Ostrick and A.~Padee and P.~Pagano and S.~Panebianco and R.~Panknin and D.~Panzieri and S.~Paul and B.~Pawlukiewicz-Kaminska and D.V.~Peshekhonov and V.D.~Peshekhonov and G.~Piragino and S.~Platchkov and J.~Pochodzalla and J.~Polak and V.A.~Polyakov and J.~Pretz and S.~Procureur and C.~Quintans and J.-F.~Rajotte and S.~Ramos and V.~Rapatsky and G.~Reicherz and D.~Reggiani and A.~Richter and F.~Robinet and E.~Rocco and E.~Rondio and A.M.~Rozhdestvensky and D.I.~Ryabchikov and V.D.~Samoylenko and A.~Sandacz and H.~Santos and M.G.~Sapozhnikov and S.~Sarkar and I.A.~Savin and P.~Schiavon and C.~Schill and L.~Schmitt and P.~Schönmeier and W.~Schröder and O.Yu.~Shevchenko and H.-W.~Siebert and L.~Silva and L.~Sinha and A.N.~Sissakian and M.~Slunecka and G.I.~Smirnov and S.~Sosio and F.~Sozzi and A.~Srnka and F.~Stinzing and M.~Stolarski and V.P.~Sugonyaev and M.~Sulc and R.~Sulej and V.V.~Tchalishev and S.~Tessaro and F.~Tessarotto and A.~Teufel and L.G.~Tkatchev and G.~Venugopal and M.~Virius and N.V.~Vlassov and A.~Vossen and R.~Webb and E.~Weise and Q.~Weitzel and R.~Windmolders and S.~Wirth and W.~Wiślicki and H.~Wollny and K.~Zaremba and M.~Zavertyaev and E.~Zemlyanichkina and J.~Zhao and R.~Ziegler and A.~Zvyagin}, title = {{C}ollins and {S}ivers asymmetries for pions and kaons in muon-deuteron {DIS}}, year = {2008}, eprint = {0802.2160}, howpublished = {Phys.Lett.B673:127-135,2009}, doi = {10.1016/j.physletb.2009.01.060}, note = {arXiv:0802.2160v2} }
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The measurements of the Collins and Sivers asymmetries of identified hadrons produced in deep-inelastic scattering of 160 GeV/c muons on a transversely polarised 6LiD target at COMPASS are presented. The results for charged pions and charged and neutral kaons correspond to all data available, which were collected from 2002 to 2004. For all final state particles both the Collins and Sivers asymmetries turn out to be small, compatible with zero within the statistical errors, in line with the previously published results for not identified charged hadrons, and with the expected cancellation between the u- and d-quark contributions.
Rho^0 meson production in the pp ->pppi+pi- reaction at 3.67 GeV/c
F. Balestra, Y. Bedfer, R. Bertini, L.C. Bland, A. Brenschede, F. Brochard, M.P. Bussa, Seonho Choi, M.L. Colanton, R. Dressler, M. Dzemidzic, J.-Cl. Faivre, A. Ferrero, L. Ferrero, J. Foryciarz, I. Fröhlich, V. Frolov, R. Garfagnini, A. Grasso, S. Heinz, et al (15)
Sep 04 2002 hep-ex arXiv:hep-ex/0209004v1

@misc{hep-ex/0209004, author = {F.~Balestra and Y.~Bedfer and R.~Bertini and L.C.~Bland and A.~Brenschede and F.~Brochard and M.P.~Bussa and Seonho Choi and M.L.~Colanton and R.~Dressler and M.~Dzemidzic and J.-Cl.~Faivre and A.~Ferrero and L.~Ferrero and J.~Foryciarz and I.~Fröhlich and V.~Frolov and R.~Garfagnini and A.~Grasso and S.~Heinz and W.W.~Jacobs and W.~Kühn and A.~Maggiora and M.~Maggiora and A.~Manara and D.~Panzieri and H.-W.~Pfaff and G.~Piragino and A.~Popov and J.~Ritman and P.~Salabura and V.~Tchalyshev and F.~Tosello and S.E.~Vigdor and G.~Zosi}, title = {{R}ho^0 meson production in the pp ->pppi+pi- reaction at 3.67 {G}e{V}/c}, year = {2002}, eprint = {hep-ex/0209004}, howpublished = {Phys.Rev.Lett. 89 (2002) 092001}, doi = {10.1103/PhysRevLett.89.092001}, note = {arXiv:hep-ex/0209004v1} }
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Total and differential cross sections for the exclusive reaction pp->pp rho^0 observed via the pi+pi- decay channel have been measured at beam momentum=3.67 GeV/c. The observed total meson production cross section is determined to be 23.4 +- 0.8 +-8 microb and is significantly lower than typical cross sections used in model calculations for heavy ion collisions. The differential cross sections measured indicate a strong anisotropy cos^2(theta^CM) in the rho^0 meson production.
Spin Transfer in Exclusive Lambda Production from pp Collisions at 3.67 GeV/c
DISTO Collaboration, F. Balestra, Y. Bedfer, R. Bertini, L.C. Bland, A. Brenschede, F. Brochard, M.P. Bussa, V. Chalyshev, Seonho Choi, M. Debowski, M. Dzemidzic, J.-Cl. Faivre, I.V. Falomkin, L. Fava, L. Ferrero, J. Foryciarz, V. Frolov, R. Garfagnini, D. Gill, et al (18)
Jun 24 1999 nucl-ex hep-ex arXiv:nucl-ex/9906011v1

@misc{nucl-ex/9906011, author = {DISTO Collaboration and F.~Balestra and Y.~Bedfer and R.~Bertini and L.C.~Bland and A.~Brenschede and F.~Brochard and M.P.~Bussa and V.~Chalyshev and Seonho Choi and M.~Debowski and M.~Dzemidzic and J.-Cl.~Faivre and I.V.~Falomkin and L.~Fava and L.~Ferrero and J.~Foryciarz and V.~Frolov and R.~Garfagnini and D.~Gill and A.~Grasso and S.~Heinz and V.V.~Ivanov and W.W.~Jacobs and W.~Kuehn and A.~Maggiora and M.~Maggiora and A.~Manara and D.~Panzieri and H.-W.~Pfaff and G.~Piragino and G.B.~Pontecorvo and A.~Popov and J.~Ritman and P.~Salabura and F.~Tosello and S.E.~Vigdor and G.~Zosi}, title = {{S}pin {T}ransfer in {E}xclusive {L}ambda {P}roduction from pp {C}ollisions at 3.67 {G}e{V}/c}, year = {1999}, eprint = {nucl-ex/9906011}, howpublished = {Phys.Rev.Lett. 83 (1999) 1534-1537}, doi = {10.1103/PhysRevLett.83.1534}, note = {arXiv:nucl-ex/9906011v1} }
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We report the first polarization transfer measurements for exclusive hyperon production reactions. The normal spin transfer coefficient DNN for pp -> p K+ Lambda is large and negative for forward Lambda production at a beam momentum of 3.67 GeV/c, a result qualitatively consistent with expectations for a mechanism dominated by kaon-exchange and rescattering. The sign of DNN is opposite to that observed in the fragmentation regime for inclusive Lambda production at much higher energies.