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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} }
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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} }
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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} }
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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} }
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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} }
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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} }
PDF
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} }
PDF
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} }
PDF
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.
Inclusive J/psi production in pp collisions at sqrt(s) = 2.76 TeV
ALICE Collaboration, B. Abelev, J. Adam, D. Adamova, A.M. Adare, M.M. Aggarwal, G. Aglieri Rinella, A.G. Agocs, A. Agostinelli, S. Aguilar Salazar, Z. Ahammed, A. Ahmad Masoodi, N. Ahmad, S.U. Ahn, A. Akindinov, D. Aleksandrov, B. Alessandro, R. Alfaro Molina, A. Alici, A. Alkin, et al (953)
Mar 19 2012 hep-ex arXiv:1203.3641v2

@misc{1203.3641, author = {ALICE Collaboration and B.~Abelev and J.~Adam and D.~Adamova and A.M.~Adare and M.M.~Aggarwal and G.~Aglieri Rinella and A.G.~Agocs and A.~Agostinelli and S.~Aguilar Salazar and Z.~Ahammed and A.~Ahmad Masoodi and N.~Ahmad and S.U.~Ahn and A.~Akindinov and D.~Aleksandrov and B.~Alessandro and R.~Alfaro Molina and A.~Alici and A.~Alkin and E.~Almaraz Avina and J.~Alme and T.~Alt and V.~Altini and S.~Altinpinar and I.~Altsybeev and C.~Andrei and A.~Andronic and V.~Anguelov and J.~Anielski and C.~Anson and T.~Anticic and F.~Antinori and P.~Antonioli and L.~Aphecetche and H.~Appelshauser and N.~Arbor and S.~Arcelli and A.~Arend and N.~Armesto and R.~Arnaldi and T.~Aronsson and I.C.~Arsene and M.~Arslandok and A.~Asryan and A.~Augustinus and R.~Averbeck and T.C.~Awes and J.~Aysto and M.D.~Azmi and M.~Bach and A.~Badala and Y.W.~Baek and R.~Bailhache and R.~Bala and R.~Baldini Ferroli and A.~Baldisseri and A.~Baldit and F.~Baltasar Dos Santos Pedrosa and J.~Ban and R.C.~Baral and R.~Barbera and F.~Barile and G.G.~Barnafoldi and L.S.~Barnby and V.~Barret and J.~Bartke and M.~Basile and N.~Bastid and B.~Bathen and G.~Batigne and B.~Batyunya and C.~Baumann and I.G.~Bearden and H.~Beck and I.~Belikov and F.~Bellini and R.~Bellwied and E.~Belmont-Moreno and G.~Bencedi and S.~Beole and I.~Berceanu and A.~Bercuci and Y.~Berdnikov and D.~Berenyi and C.~Bergmann and D.~Berzano and L.~Betev and A.~Bhasin and A.K.~Bhati and L.~Bianchi and N.~Bianchi and C.~Bianchin and J.~Bielcik and J.~Bielcikova and S.~Bjelogrlic and F.~Blanco and F.~Blanco and D.~Blau and C.~Blume and M.~Boccioli and N.~Bock and A.~Bogdanov and H.~Boggild and M.~Bogolyubsky and L.~Boldizsar and M.~Bombara and J.~Book and H.~Borel and A.~Borissov and S.~Bose and F.~Bossu and M.~Botje and S.~Bottger and B.~Boyer and E.~Braidot and P.~Braun-Munzinger and M.~Bregant and T.~Breitner and T.A.~Browning and M.~Broz and R.~Brun and E.~Bruna and G.E.~Bruno and D.~Budnikov and H.~Buesching and S.~Bufalino and K.~Bugaiev and O.~Busch and Z.~Buthelezi and D.~Caballero Orduna and D.~Caffarri and X.~Cai and H.~Caines and E.~Calvo Villar and P.~Camerini and V.~Canoa Roman and G.~Cara Romeo and W.~Carena and F.~Carena and N.~Carlin Filho and F.~Carminati and C.A.~Carrillo Montoya and A.~Casanova Diaz and J.~Castillo Castellanos and J.F.~Castillo Hernandez and E.A.R.~Casula and V.~Catanescu and C.~Cavicchioli and J.~Cepila and P.~Cerello and B.~Chang and S.~Chapeland and J.L.~Charvet and S.~Chattopadhyay and S.~Chattopadhyay and I.~Chawla and M.~Cherney and C.~Cheshkov and B.~Cheynis and E.~Chiavassa and V.~Chibante Barroso and D.D.~Chinellato and P.~Chochula and M.~Chojnacki and P.~Christakoglou and C.H.~Christensen and P.~Christiansen and T.~Chujo and S.U.~Chung and C.~Cicalo and L.~Cifarelli and F.~Cindolo and J.~Cleymans and F.~Coccetti and F.~Colamaria and D.~Colella and G.~Conesa Balbastre and Z.~Conesa del Valle and P.~Constantin and G.~Contin and J.G.~Contreras and T.M.~Cormier and Y.~Corrales Morales and P.~Cortese and I.~Cortes Maldonado and M.R.~Cosentino and F.~Costa and M.E.~Cotallo and E.~Crescio and P.~Crochet and E.~Cruz Alaniz and E.~Cuautle and L.~Cunqueiro and A.~Dainese and H.H.~Dalsgaard and A.~Danu and K.~Das and I.~Das and D.~Das and A.~Dash and S.~Dash and S.~De and G.O.V.~de Barros and A.~De Caro and G.~de Cataldo and J.~de Cuveland and A.~De Falco and D.~De Gruttola and H.~Delagrange and E.~Del Castillo Sanchez and A.~Deloff and V.~Demanov and N.~De Marco and E.~Denes and S.~De Pasquale and A.~Deppman and G.~D Erasmo and R.~de Rooij and M.A.~Diaz Corchero and D.~Di Bari and T.~Dietel and C.~Di Giglio and S.~Di Liberto and A.~Di Mauro and P.~Di Nezza and R.~Divia and O.~Djuvsland and A.~Dobrin and T.~Dobrowolski and I.~Dominguez and B.~Donigus and O.~Dordic and O.~Driga and A.K.~Dubey and L.~Ducroux and P.~Dupieux and A.K.~Dutta Majumdar and M.R.~Dutta Majumdar and D.~Elia and D.~Emschermann and H.~Engel and H.A.~Erdal and B.~Espagnon and M.~Estienne and S.~Esumi and D.~Evans and G.~Eyyubova and D.~Fabris and J.~Faivre and D.~Falchieri and A.~Fantoni and M.~Fasel and R.~Fearick and A.~Fedunov and D.~Fehlker and L.~Feldkamp and D.~Felea and G.~Feofilov and A.~Fernandez Tellez and E.G.~Ferreiro and A.~Ferretti and R.~Ferretti and J.~Figiel and M.A.S.~Figueredo and S.~Filchagin and D.~Finogeev and F.M.~Fionda and E.M.~Fiore and M.~Floris and S.~Foertsch and P.~Foka and S.~Fokin and E.~Fragiacomo and M.~Fragkiadakis and U.~Frankenfeld and U.~Fuchs and C.~Furget and M.~Fusco Girard and J.J.~Gaardhoje and M.~Gagliardi and A.~Gago and M.~Gallio and D.R.~Gangadharan and P.~Ganoti and C.~Garabatos and E.~Garcia-Solis and I.~Garishvili and J.~Gerhard and M.~Germain and C.~Geuna and A.~Gheata and M.~Gheata and B.~Ghidini and P.~Ghosh and P.~Gianotti and M.R.~Girard and P.~Giubellino and E.~Gladysz-Dziadus and P.~Glassel and R.~Gomez and L.H.~Gonzalez-Trueba and P.~Gonzalez-Zamora and S.~Gorbunov and A.~Goswami and S.~Gotovac and V.~Grabski and L.K.~Graczykowski and R.~Grajcarek and A.~Grelli and A.~Grigoras and C.~Grigoras and V.~Grigoriev and A.~Grigoryan and S.~Grigoryan and B.~Grinyov and N.~Grion and P.~Gros and J.F.~Grosse-Oetringhaus and J.-Y.~Grossiord and R.~Grosso and F.~Guber and R.~Guernane and C.~Guerra Gutierrez and B.~Guerzoni and M.Guilbaud and K.~Gulbrandsen and T.~Gunji and A.~Gupta and R.~Gupta and H.~Gutbrod and O.~Haaland and C.~Hadjidakis and M.~Haiduc and H.~Hamagaki and G.~Hamar and B.H.~Han and L.D.~Hanratty and A.~Hansen and Z.~Harmanova and J.W.~Harris and M.~Hartig and D.~Hasegan and D.~Hatzifotiadou and A.~Hayrapetyan and S.T.~Heckel and M.~Heide and H.~Helstrup and A.~Herghelegiu and G.~Herrera Corral and N.~Herrmann and K.F.~Hetland and B.~Hicks and P.T.~Hille and B.~Hippolyte and T.~Horaguchi and Y.~Hori and P.~Hristov and I.~Hrivnacova and M.~Huang and S.~Huber and T.J.~Humanic and D.S.~Hwang and R.~Ichou and R.~Ilkaev and I.~Ilkiv and M.~Inaba and E.~Incani and G.M.~Innocenti and P.G.~Innocenti and M.~Ippolitov and M.~Irfan and C.~Ivan and V.~Ivanov and A.~Ivanov and M.~Ivanov and O.~Ivanytskyi and A.~Jacholkowski and P.~M.~Jacobs and L.~Jancurova and H.J.~Jang and S.~Jangal and M.A.~Janik and R.~Janik and P.H.S.Y.~Jayarathna and S.~Jena and R.T.~Jimenez Bustamante and L.~Jirden and P.G.~Jones and H.~Jung and A.~Jusko and A.B.~Kaidalov and V.~Kakoyan and S.~Kalcher and P.~Kalinak and M.~Kalisky and T.~Kalliokoski and A.~Kalweit and K.~Kanaki and J.H.~Kang and V.~Kaplin and A.~Karasu Uysal and O.~Karavichev and T.~Karavicheva and E.~Karpechev and A.~Kazantsev and U.~Kebschull and R.~Keidel and M.M.~Khan and S.A.~Khan and P.~Khan and A.~Khanzadeev and Y.~Kharlov and B.~Kileng and M.~Kim and J.S.~Kim and D.J.~Kim and T.~Kim and B.~Kim and S.~Kim and S.H.~Kim and D.W.~Kim and J.H.~Kim and S.~Kirsch and I.~Kisel and S.~Kiselev and A.~Kisiel and J.L.~Klay and J.~Klein and C.~Klein-Bosing and M.~Kliemant and A.~Kluge and M.L.~Knichel and A.G.~Knospe and K.~Koch and M.K.~Kohler and A.~Kolojvari and V.~Kondratiev and N.~Kondratyeva and A.~Konevskikh and A.~Korneev and C.~Kottachchi Kankanamge Don and R.~Kour and M.~Kowalski and S.~Kox and G.~Koyithatta Meethaleveedu and J.~Kral and I.~Kralik and F.~Kramer and I.~Kraus and T.~Krawutschke and M.~Krelina and M.~Kretz and M.~Krivda and F.~Krizek and M.~Krus and E.~Kryshen and M.~Krzewicki and Y.~Kucheriaev and C.~Kuhn and P.G.~Kuijer and P.~Kurashvili and A.~Kurepin and A.B.~Kurepin and A.~Kuryakin and S.~Kushpil and V.~Kushpil and H.~Kvaerno and M.J.~Kweon and Y.~Kwon and P.~Ladron de Guevara and I.~Lakomov and R.~Langoy and C.~Lara and A.~Lardeux and P.~La Rocca and C.~Lazzeroni and R.~Lea and Y.~Le Bornec and S.C.~Lee and K.S.~Lee and F.~Lefevre and J.~Lehnert and L.~Leistam and M.~Lenhardt and V.~Lenti and H.~Leon and I.~Leon Monzon and H.~Leon Vargas and P.~Levai and J.~Lien and R.~Lietava and S.~Lindal and V.~Lindenstruth and C.~Lippmann and M.A.~Lisa and L.~Liu and P.I.~Loenne and V.R.~Loggins and V.~Loginov and S.~Lohn and D.~Lohner and C.~Loizides and K.K.~Loo and X.~Lopez and E.~Lopez Torres and G.~Lovhoiden and X.-G.~Lu and P.~Luettig and M.~Lunardon and J.~Luo and G.~Luparello and L.~Luquin and C.~Luzzi and K.~Ma and R.~Ma and D.M.~Madagodahettige-Don and A.~Maevskaya and M.~Mager and D.P.~Mahapatra and A.~Maire and M.~Malaev and I.~Maldonado Cervantes and L.~Malinina and D.~Mal'Kevich and P.~Malzacher and A.~Mamonov and L.~Manceau and L.~Mangotra and V.~Manko and F.~Manso and V.~Manzari and Y.~Mao and M.~Marchisone and J.~Mares and G.V.~Margagliotti and A.~Margotti and A.~Marin and C.A.~Marin Tobon and C.~Markert and I.~Martashvili and P.~Martinengo and M.I.~Martinez and A.~Martinez Davalos and G.~Martinez Garcia and Y.~Martynov and A.~Mas and S.~Masciocchi and M.~Masera and A.~Masoni and L.~Massacrier and M.~Mastromarco and A.~Mastroserio and Z.L.~Matthews and A.~Matyja and D.~Mayani and C.~Mayer and J.~Mazer and M.A.~Mazzoni and F.~Meddi and A.~Menchaca-Rocha and J.~Mercado Perez and M.~Meres and Y.~Miake and L.~Milano and J.~Milosevic and A.~Mischke and A.N.~Mishra and D.~Miskowiec and C.~Mitu and J.~Mlynarz and A.K.~Mohanty and B.~Mohanty and L.~Molnar and L.~Montano Zetina and M.~Monteno and E.~Montes and T.~Moon and M.~Morando and D.A.~Moreira De Godoy and S.~Moretto and A.~Morsch and V.~Muccifora and E.~Mudnic and S.~Muhuri and H.~Muller and M.G.~Munhoz and L.~Musa and A.~Musso and B.K.~Nandi and R.~Nania and E.~Nappi and C.~Nattrass and N.P.Naumov and S.~Navin and T.K.~Nayak and S.~Nazarenko and G.~Nazarov and A.~Nedosekin and M.~Nicassio and B.S.~Nielsen and T.~Niida and S.~Nikolaev and V.~Nikolic and V.~Nikulin and S.~Nikulin and B.S.~Nilsen and M.S.~Nilsson and F.~Noferini and P.~Nomokonov and G.~Nooren and N.~Novitzky and A.~Nyanin and A.~Nyatha and C.~Nygaard and J.~Nystrand and A.~Ochirov and H.~Oeschler and S.K.~Oh and S.~Oh and J.~Oleniacz and C.~Oppedisano and A.~Ortiz Velasquez and G.~Ortona and A.~Oskarsson and P.~Ostrowski and J.~Otwinowski and G.~Ovrebekk and K.~Oyama and K.~Ozawa and Y.~Pachmayer and M.~Pachr and F.~Padilla and P.~Pagano and G.~Paic and F.~Painke and C.~Pajares and S.K.~Pal and S.~Pal and A.~Palaha and A.~Palmeri and V.~Papikyan and G.S.~Pappalardo and W.J.~Park and A.~Passfeld and B.~Pastircak and D.I.~Patalakha and V.~Paticchio and A.~Pavlinov and T.~Pawlak and T.~Peitzmann and E.~Pereira De Oliveira Filho and D.~Peresunko and C.E.~Perez Lara and E.~Perez Lezama and D.~Perini and D.~Perrino and W.~Peryt and A.~Pesci and V.~Peskov and Y.~Pestov and V.~Petracek and M.~Petran and M.~Petris and P.~Petrov and M.~Petrovici and C.~Petta and S.~Piano and A.~Piccotti and M.~Pikna and P.~Pillot and O.~Pinazza and L.~Pinsky and N.~Pitz and F.~Piuz and D.B.~Piyarathna and M.~Ploskon and J.~Pluta and T.~Pocheptsov and S.~Pochybova and P.L.M.~Podesta-Lerma and M.G.~Poghosyan and K.~Polak and B.~Polichtchouk and A.~Pop and S.~Porteboeuf-Houssais and V.~Pospisil and B.~Potukuchi and S.K.~Prasad and R.~Preghenella and F.~Prino and C.A.~Pruneau and I.~Pshenichnov and S.~Puchagin and G.~Puddu and J.~Pujol Teixido and A.~Pulvirenti and V.~Punin and M.~Putis and J.~Putschke and E.~Quercigh and H.~Qvigstad and A.~Rachevski and A.~Rademakers and S.~Radomski and T.S.~Raiha and J.~Rak and A.~Rakotozafindrabe and L.~Ramello and A.~Ramirez Reyes and S.~Raniwala and R.~Raniwala and S.S.~Rasanen and B.T.~Rascanu and D.~Rathee and K.F.~Read and J.S.~Real and K.~Redlich and P.~Reichelt and M.~Reicher and R.~Renfordt and A.R.~Reolon and A.~Reshetin and F.~Rettig and J.-P.~Revol and K.~Reygers and L.~Riccati and R.A.~Ricci and T.~Richert and M.~Richter and P.~Riedler and W.~Riegler and F.~Riggi and M.~Rodriguez Cahuantzi and K.~Roed and D.~Rohr and D.~Rohrich and R.~Romita and F.~Ronchetti and P.~Rosnet and S.~Rossegger and A.~Rossi and F.~Roukoutakis and C.~Roy and P.~Roy and A.J.~Rubio Montero and R.~Rui and E.~Ryabinkin and A.~Rybicki and S.~Sadovsky and K.~Safarik and R.~Sahoo and P.K.~Sahu and J.~Saini and H.~Sakaguchi and S.~Sakai and D.~Sakata and C.A.~Salgado and J.~Salzwedel and S.~Sambyal and V.~Samsonov and X.~Sanchez Castro and L.~Sandor and A.~Sandoval and S.~Sano and M.~Sano and R.~Santo and R.~Santoro and J.~Sarkamo and E.~Scapparone and F.~Scarlassara and R.P.~Scharenberg and C.~Schiaua and R.~Schicker and H.R.~Schmidt and C.~Schmidt and S.~Schreiner and S.~Schuchmann and J.~Schukraft and Y.~Schutz and K.~Schwarz and K.~Schweda and G.~Scioli and E.~Scomparin and P.A.~Scott and R.~Scott and G.~Segato and I.~Selyuzhenkov and S.~Senyukov and J.~Seo and S.~Serci and E.~Serradilla and A.~Sevcenco and I.~Sgura and A.~Shabetai and G.~Shabratova and R.~Shahoyan and N.~Sharma and S.~Sharma and K.~Shigaki and M.~Shimomura and K.~Shtejer and Y.~Sibiriak and M.~Siciliano and E.~Sicking and S.~Siddhanta and T.~Siemiarczuk and D.~Silvermyr and C.~Silvestre and G.~Simonetti and R.~Singaraju and R.~Singh and S.~Singha and T.~Sinha and B.C.~Sinha and B.~Sitar and M.~Sitta and T.B.~Skaali and K.~Skjerdal and R.~Smakal and N.~Smirnov and R.J.M.~Snellings and C.~Sogaard and R.~Soltz and H.~Son and M.~Song and J.~Song and C.~Soos and F.~Soramel and I.~Sputowska and M.~Spyropoulou-Stassinaki and B.K.~Srivastava and J.~Stachel and I.~Stan and I.~Stan and G.~Stefanek and G.~Stefanini and T.~Steinbeck and M.~Steinpreis and E.~Stenlund and G.~Steyn and D.~Stocco and M.~Stolpovskiy and K.~Strabykin and P.~Strmen and A.A.P.~Suaide and M.A.~Subieta Vasquez and T.~Sugitate and C.~Suire and M.~Sukhorukov and R.~Sultanov and M.~Sumbera and T.~Susa and A.~Szanto de Toledo and I.~Szarka and A.~Szostak and C.~Tagridis and J.~Takahashi and J.D.~Tapia Takaki and A.~Tauro and G.~Tejeda Munoz and A.~Telesca and C.~Terrevoli and J.~Thader and D.~Thomas and R.~Tieulent and A.R.~Timmins and D.~Tlusty and A.~Toia and H.~Torii and L.~Toscano and F.~Tosello and D.~Truesdale and W.H.~Trzaska and T.~Tsuji and A.~Tumkin and R.~Turrisi and T.S.~Tveter and J.~Ulery and K.~Ullaland and J.~Ulrich and A.~Uras and J.~Urban and G.M.~Urciuoli and G.L.~Usai and M.~Vajzer and M.~Vala and L.~Valencia Palomo and S.~Vallero and N.~van der Kolk and P.~Vande Vyvre and M.~van Leeuwen and L.~Vannucci and A.~Vargas and R.~Varma and M.~Vasileiou and A.~Vasiliev and V.~Vechernin and M.~Veldhoen and M.~Venaruzzo and E.~Vercellin and S.~Vergara and D.C.~Vernekohl and R.~Vernet and M.~Verweij and L.~Vickovic and G.~Viesti and O.~Vikhlyantsev and Z.~Vilakazi and O.~Villalobos Baillie and A.~Vinogradov and Y.~Vinogradov and L.~Vinogradov and T.~Virgili and Y.P.~Viyogi and A.~Vodopyanov and S.~Voloshin and K.~Voloshin and G.~Volpe and B.~von Haller and D.~Vranic and J.~Vrlakova and B.~Vulpescu and A.~Vyushin and B.~Wagner and V.~Wagner and R.~Wan and Y.~Wang and D.~Wang and Y.~Wang and M.~Wang and K.~Watanabe and J.P.~Wessels and U.~Westerhoff and J.~Wiechula and J.~Wikne and M.~Wilde and G.~Wilk and A.~Wilk and M.C.S.~Williams and B.~Windelband and L.~Xaplanteris Karampatsos and H.~Yang and S.~Yang and S.~Yasnopolskiy and J.~Yi and Z.~Yin and H.~Yokoyama and I.-K.~Yoo and J.~Yoon and W.~Yu and X.~Yuan and I.~Yushmanov and C.~Zach and C.~Zampolli and S.~Zaporozhets and A.~Zarochentsev and P.~Zavada and N.~Zaviyalov and H.~Zbroszczyk and P.~Zelnicek and I.S.~Zgura and M.~Zhalov and X.~Zhang and D.~Zhou and Y.~Zhou and F.~Zhou and X.~Zhu and A.~Zichichi and A.~Zimmermann and G.~Zinovjev and Y.~Zoccarato and M.~Zynovyev}, title = {{I}nclusive {J}/psi production in pp collisions at sqrt(s) = 2.76 {T}e{V}}, year = {2012}, eprint = {1203.3641}, doi = {10.1103/PhysRevE.87.025001}, note = {arXiv:1203.3641v2} }
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The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.
The polarized TMDs in the covariant parton model approach
A.V. Efremov, P. Schweitzer, O.V. Teryaev, P. Zavada
Jan 22 2011 hep-ph hep-ex arXiv:1101.4035v1

@misc{1101.4035, author = {A.V.~Efremov and P.~Schweitzer and O.V.~Teryaev and P.~Zavada}, title = {{T}he polarized {TMD}s in the covariant parton model approach}, year = {2011}, eprint = {1101.4035}, howpublished = {J.Phys.Conf.Ser.295:012052,2011}, doi = {10.1088/1742-6596/295/1/012052}, note = {arXiv:1101.4035v1} }
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We derive relations between polarized transverse momentum dependent distribution functions (TMDs) and the usual parton distribution functions (PDFs) in the 3D covariant parton model, which follow from Lorentz invariance and the assumption of a rotationally symmetric distribution of parton momenta in the nucleon rest frame. Using the known PDF $g_{1}^{q}(x)$ as input we predict the $x$- and $\mathbf{p}_{T}$-dependence of all polarized twist-2 naively time-reversal even (T-even) TMDs.
The relation between TMDs and PDFs in the covariant parton model approach
A.V.Efremov, P.Schweitzer, O.V.Teryaev, P.Zavada
Dec 24 2010 hep-ph hep-ex arXiv:1012.5296v1

@misc{1012.5296, author = {A.V.Efremov and P.Schweitzer and O.V.Teryaev and P.Zavada}, title = {{T}he relation between {TMD}s and {PDF}s in the covariant parton model approach}, year = {2010}, eprint = {1012.5296}, howpublished = {Phys.Rev.D83:054025,2011}, doi = {10.1103/PhysRevD.83.054025}, note = {arXiv:1012.5296v1} }
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We derive relations between transverse momentum dependent distribution functions (TMDs) and the usual parton distribution functions (PDFs) in the 3D covariant parton model, which follow from Lorentz invariance and the assumption of a rotationally symmetric distribution of parton momenta in the nucleon rest frame. Using the known PDFs f_1(x) and g_1(x) as input we predict the x- and pT-dependence of all twist-2 T-even TMDs.
Quark orbital angular momentum: can we learn about it from GPDs and TMDs?
H.Avakian, A.V.Efremov, P.Schweitzer, O.V.Teryaev, P.Zavada
Aug 12 2010 hep-ph hep-ex hep-lat arXiv:1008.1921v1

@misc{1008.1921, author = {H.Avakian and A.V.Efremov and P.Schweitzer and O.V.Teryaev and P.Zavada}, title = {{Q}uark orbital angular momentum: can we learn about it from {GPD}s and {TMD}s?}, year = {2010}, eprint = {1008.1921}, note = {arXiv:1008.1921v1} }
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It is known how to access information on quark orbital angular momentum from generalized parton distribution functions, in a certain specified framework. It is intuitively expected, that such information can be accessed also through transverse momentum dependent distribution functions, but not known how. Now quark models provide promising hints. Recent results are reviewed.