PKS 1622-297 is a blazar[1][2] located in the constellation of Scorpius. It is one of the brightest objects of its type in the gamma ray region.[3] It has a redshift of (z) 0.815.[4] This blazar was first discovered as a compact astronomical radio source in 1970 by astronomers who were conducting interferometer observations[5] and identified with an optical counterpart in 1984.[6] In addition, the radio spectrum of the source appears flat, making it a flat-spectrum radio quasar (FRSQ).[7][8]
| PKS 1622-297 | |
|---|---|
 The blazar PKS 1622-297. | |
| Observation data (J2000.0 epoch) | |
| Constellation | Scorpius |
| Right ascension | 16h 26m 06.020s |
| Declination | −29° 51′ 26.971″ |
| Redshift | 0.813800 |
| Heliocentric radial velocity | 243,971 km/s |
| Distance | 6.885 Gly |
| Apparent magnitude (V) | 20.5 |
| Apparent magnitude (B) | 18.41 |
| Characteristics | |
| Type | Blazar, LPQ, FRSQ |
| Notable features | Gamma ray emitting blazar |
| Other designations | |
| LEDA 2828823, 4FGL J1626.0-2950, QSO B1622-297, Cul 1622-297, 2CXO J162606.0-295126, PKS B1622-297 | |
Description
editPKS 1622-297 produced a powerful gamma ray outburst in June and July 1995. This was detected by Energetic Gamma Ray Experiment Telescope (EGRET) in the year 1995, where its outburst in the energy range above 100 MeV lasted for a period of five weeks. However no presence of MeV emission was detected.[7] A major flare in PKS 1622-297 was observed by EGRET, and lasted around two days.[9] Subsequent optical observations in 1996 and 1997 as well as three nights in 2001, showed the source is much fainter.[10] Two other flares were detected in March 2010 and July 2014.[11][12]
A three-week radio, optical and X-ray campaign was conducted on PKS 1622–297 by the Rossi X-ray Timing Explorer as well as the University of Michigan Radio Astronomy Observatory and optical telescopes at Cerro Tololo Inter-American Observatory in Chile. Results indicated the object was a weak X-ray emitter and was also redder during its bright optical flux state.[13]
Radio images made of the object via Very Long Baseline Interferometry observations showed the source having an elongated structure towards the west on parsec scales. Three components are found in a form of a bright core and two weak jet components showing superluminal motion reaching up to 12.1 h−1 c.[14] There is a jet along the position angle of 69°, made up of a prominent component 15 mas from the core with a diffused structure extending out to 30 mas.[15] However a VLBI Space Observatory Programme (VSOP) image shows it having a weak component and a strong core. In an Australia Telescope Compact Array (ATCA) imaging at 4.8 GHz, the source has a bright core with strong extended emission in form of two components. These components are placed in equal angular distances on sides of the core and of similar brightness and sizes.[16]
The supermassive black hole in PKS 1622-297 is estimated to be 8 x 108 Mʘ with the limit of the Schwarzschild radius being Rg > 2.5 x 1014 centimeters.[4]
References
edit- ^ Collmar, W.; Schönfelder, V.; Bloemen, H.; Blom, J. J.; Hermsen, W.; McConnell, M.; Stacy, J. G.; Bennett, K.; Williams, O. R. (1997-05-01). "Evidence for γ-ray flares in 3C 279 and PKS 1622-297 at ~10 MeV". Proceedings of the Fourth Compton Symposium. 410: 1341–1345. arXiv:astro-ph/9711111. Bibcode:1997AIPC..410.1341C. doi:10.1063/1.54054.
- ^ Writer, Staff. "Gamma ray: Observatory discovers spectacular, energetic flare". The Stockton Record. Retrieved 2024-11-10.
- ^ Fan, J. H.; Xie, G. Z.; Bacon, R. (1999-04-01). "The central black hole masses and Doppler factors of the gamma -ray loud blazars" (PDF). Astronomy and Astrophysics Supplement Series. 136: 13–18. arXiv:astro-ph/9910358. Bibcode:1999A&AS..136...13F. doi:10.1051/aas:1999194. ISSN 0365-0138.
- ^ a b Mattox, J. R.; Wagner, S. J.; Malkan, M.; McGlynn, T. A.; Schachter, J. F.; Grove, J. E.; Johnson, W. N.; Kurfess, J. D. (1997-02-20). "An Intense Gamma-Ray Flare of PKS 1622−297". The Astrophysical Journal. 476 (2): 692–697. arXiv:astro-ph/9610007. Bibcode:1997ApJ...476..692M. doi:10.1086/303639. ISSN 0004-637X.
- ^ Broderick, J. J.; Kellermann, K. I.; Shaffer, D. B.; Jauncey, D. L. (March 1972). "High-Resolution Observations of Compact Radio Sources at 13 Centimeters. II". The Astrophysical Journal. 172: 299. Bibcode:1972ApJ...172..299B. doi:10.1086/151347. ISSN 0004-637X.
- ^ Torres, C.; Wroblewski, H. (December 1984). "Optical counterpart candidates of radio sources 1320 - 446, 1622 - 297, 1908 - 202, and 2106 - 413". Astronomy & Astrophysics. 141 (1): 271–273. Bibcode:1984A&A...141..271T. ISSN 0004-6361.
- ^ a b Zhang, S.; Collmar, W.; Bennett, K.; Bloemen, H.; Hermsen, W.; McConnell, M.; Reimer, O.; Schönfelder, V.; Wagner, S. J.; Williams, O. R. (May 2002). "COMPTEL observations of the gamma-ray blazar PKS 1622-297" (PDF). Astronomy & Astrophysics. 386 (3): 843–853. arXiv:astro-ph/0203231. Bibcode:2002A&A...386..843Z. doi:10.1051/0004-6361:20020267. ISSN 0004-6361.
- ^ Lister, Matthew. "MOJAVE Sample: 1622-297". www.cv.nrao.edu. Retrieved 2024-11-10.
- ^ Zhang, S.; Collmar, W.; Bennett, K.; Bloemen, H.; Hermsen, W.; McConnell, M.; Reimer, O.; Schönfelder, V.; Wagner, S. J.; Williams, O. R. (May 2002). "COMPTEL observations of the gamma-ray blazar PKS 1622-297 during a gamma-ray high state in 1995". Astronomy & Astrophysics. 386 (3): 843–853. arXiv:astro-ph/0203231. Bibcode:2002A&A...386..843Z. doi:10.1051/0004-6361:20020267. ISSN 0004-6361.
- ^ Kent, B. R.; Webb, J. R. (2001-12-01). "Optical Observations of the Gamma-ray Blazar PKS 1622-297". American Astronomical Society. 199: 98.03. Bibcode:2001AAS...199.9803K.
- ^ Buson, S. (2014-07-01). "Fermi LAT detection of a GeV flare from PKS 1622-29". The Astronomer's Telegram. 6327: 1. Bibcode:2014ATel.6327....1B.
- ^ Buxton, M.; Bailyn, C.; Bonning, E.; Chatterjee, R.; Coppi, P.; Isler, J.; Scalzo, R.; Urry, M.; Maraschi, L.; Fossati, G. (2010-03-01). "Optical and IR flare of blazar PKS B 1622-297". The Astronomer's Telegram. 2522: 1. Bibcode:2010ATel.2522....1B.
- ^ Meyer, Angela Osterman; Miller, H. Richard; Marshall, Kevin; Ryle, Wesley T.; Aller, Hugh; Aller, Margo; McFarland, John P.; Pollock, Joseph T.; Reichart, Daniel E.; Crain, J. Adam; Ivarsen, Kevin M.; LaCluyze, Aaron P.; Nysewander, Melissa C. (2008-08-15). "Results of the First Simultaneous X-ray, Optical and Radio Campaign on the Blazar PKS 1622-297". The Astronomical Journal. 136 (3): 1398–1405. Bibcode:2008AJ....136.1398O. doi:10.1088/0004-6256/136/3/1398. ISSN 0004-6256.
- ^ Wajima, Kiyoaki; Bignall, Hayley E.; Kobayashi, Hideyuki; Hirabayashi, Hisashi; Murata, Yasuhiro; Edwards, Philip G.; Tsuboi, Masato; Fujisawa, Kenta (2006-04-25). "Milliarcsecond-Scale Structure in the Gamma-Ray Loud Quasar PKS 1622−297". Publications of the Astronomical Society of Japan. 58 (2): 223–232. doi:10.1093/pasj/58.2.223. ISSN 2053-051X.
- ^ Jorstad, Svetlana G.; Marscher, Alan P.; Mattox, John R.; Wehrle, Ann E.; Bloom, Steven D.; Yurchenko, Alexei V. (June 2001). "Multiepoch Very Long Baseline Array Observations of EGRET-detected Quasars and BL Lacertae Objects: Superluminal Motion of Gamma-Ray Bright Blazars". The Astrophysical Journal Supplement Series. 134 (2): 181–240. arXiv:astro-ph/0101570. Bibcode:2001ApJS..134..181J. doi:10.1086/320858. ISSN 0067-0049.
- ^ Tingray, S.J.; Reynolds, J.E.; Tzioumis, A.K.; Jauncey, David L.; Lovell, J.E.J.; Dodson, R.; Costa, M.E.; McCulloch, P.M. (2002). "VSOP Space VLBI and Geodetic VLBI Investigations of Southern Hemisphere Radio Sources". The Astrophysical Journal Supplement Series. 141 (2): 311–355. Bibcode:2002ApJS..141..311T. doi:10.1086/340783.