PKS 0537-441
PKS 0537-441 | |
---|---|
Observation data (J2000.0 epoch) | |
Constellation | Pictor |
Right ascension | 05h 38m 50.361s |
Declination | −44° 05′ 08.939″ |
Redshift | 0.896000 |
Heliocentric radial velocity | 268,614 km/s |
Distance | 7.335 Gly |
Apparent magnitude (V) | 16.48 |
Apparent magnitude (B) | 15.77 |
Characteristics | |
Type | Blazar, BL Lac |
Other designations | |
LEDA 2824444, IRAS F05373-4406, WMAP 148, 4FGL J0538.8-4405, 2E 1488, Cul 0537-441 |
PKS 0537-441 is a blazar[1] located in the constellation of Pictor. It has a redshift of 0.896[2] and was discovered in 1973 by an American astronomer named Olin J. Eggen, who noted it as a luminous quasar.[3] This is a BL Lacertae object in literature because of its featureless optical spectra[4][5] as well as both a possible gravitational microlensing[6] and a gravitationally lensed candidate.[7] Its radio source is found compact and is characterized by a spectral peak in the gigahertz range, making it a gigahertz-peaked spectrum source (GPS).[8]
Description
[edit]PKS 0537-441 is found violently variable on the electromagnetic spectrum at all frequencies,[9] and is a source of gamma ray emission.[10][11] Between December 2004 and March 2005, it underwent intense activity showing more than 4 magnitudes in a V filter in 50 days and 2.5 in 10 days.[12] PKS 0537-441 is also known to display two flaring episodes, one in July 2009 and one in March 2010, with its gamma ray luminosity in the 0.1-100 GeV energy range reaching a peak value (2.6 x 1048 erg s−1) on 3-d timescales at the end of the month.[13] During its variability, PKS 0537-441 shows signs of both flux and color index variability on timescales.[14]
PKS 0537-441 contains a radio structure. The source is found to be core dominated on arcsecond scales with a secondary bright component separated by 7".2 at a 305° positional angle (PA). However, according to 2.3 GHz observations conducted by the Southern Hemisphere VLBI Experimental program (SHEVE), the radio structure has a 4.2 Jansky core with a measured diameter of 1.1 mas. There is a jetlike component, confirmed to be an asymmetric core-jet structure according to a 5 GHz Very-long-baseline interferometry imaging. This component is located north of the compact core.[15]
PKS 0537-441 shows gamma ray and optical oscillations. During its high state between August 2008 and 2011, the periodogram of its gamma ray light curve displays a peak reaching T0 ~ 280 days with significance of 99.7%.[16] A broad magnesium ionized emission line was also discovered at redshift (z) 0.885, implied to be a mini low ionization broad absorption-line quasar. This speculates PKS 0537-441 might be a binary quasar.[17]
References
[edit]- ^ Pian, E.; Falomo, R.; Hartman, R. C.; Maraschi, L.; Tavecchio, F.; Tornikoski, M.; Treves, A.; Urry, C. M.; Ballo, L.; Mukherjee, R.; Scarpa, R.; Thompson, D. J.; Pesce, J. E. (2002-09-01). "Broad-band continuum and line emission of the gamma-ray blazar PKS 0537-441". Astronomy and Astrophysics. 392 (2): 407–415. arXiv:astro-ph/0207355. Bibcode:2002A&A...392..407P. doi:10.1051/0004-6361:20020881. ISSN 0004-6361.
- ^ Li, Xiao-Pan; Luo, Yu-Hui; Zhang, Li; Yang, Cheng; Yang, Hai-Tao; Cai, Yan (2016-10-14). "SimultaneousSwiftand Rapid Eye Mount telescope observations of the blazar PKS 0537–441". Monthly Notices of the Royal Astronomical Society. 464 (4): 3972–3990. doi:10.1093/mnras/stw2652. ISSN 0035-8711.
- ^ Eggen, O. J. (November 1973). "A Very Large Light Pulse from the Object Identified with PKS 0537-441". The Astrophysical Journal. 186: L1. doi:10.1086/181344. ISSN 0004-637X.
- ^ Bechtold, Jill; Dobrzycki, Adam; Wilden, Brenda; Morita, Miwa; Scott, Jennifer; Dobrzycka, Danuta; Tran, Kim-Vy; Aldcroft, Thomas L. (June 2002). "A Uniform Analysis of the Lyα Forest at z = 0–5. III. Hubble Space Telescope Faint Object Spectrograph Spectral Atlas". The Astrophysical Journal Supplement Series. 140 (2): 143–238. doi:10.1086/342489. ISSN 0067-0049.
- ^ Tanzi, E. G.; Barr, P.; Bouchet, P.; Chiappetti, L.; Cristiani, S.; Falomo, R.; Giommi, P.; Maraschi, L.; Treves, A. (December 1986). "Multifrequency observations of the Blazar PKS 0537-441 in a moderately active state". The Astrophysical Journal. 311: L13. doi:10.1086/184789. ISSN 0004-637X.
- ^ Surpi, G. C.; Romero, G. E.; Vucetich, H. (1996-10-01). "The Gravitational Microlensing Scenario for PKS 0537--441". Revista Mexicana de Astronomia y Astrofisica. 32: 153–159. Bibcode:1996RMxAA..32..153S. ISSN 0185-1101.
- ^ Stickel, M.; Fried, J. W.; Kuehr, H. (1988-11-01). "PKS 0537-441 : a gravitationally lensed blazar ?". Astronomy and Astrophysics. 206: L30–L33. Bibcode:1988A&A...206L..30S. ISSN 0004-6361.
- ^ Torniainen, I.; Tornikoski, M.; Teräsranta, H.; Aller, M. F.; Aller, H. D. (2005-05-13). "Long term variability of gigahertz-peaked spectrum sources and candidates" (PDF). Astronomy & Astrophysics. 435 (3): 839–856. doi:10.1051/0004-6361:20041886. ISSN 0004-6361.
- ^ Pian, E.; Romano, P.; Treves, A.; Ghisellini, G.; Covino, S.; Cucchiara, A. (July 2007). "Simultaneous Swift and REM Monitoring of the Blazar PKS 0537-441 in 2005". The Astrophysical Journal. 664: 106–116. doi:10.1086/518469.
- ^ Cannon, A. (2010-04-01). "Fermi LAT detection of increasing gamma-ray activity of blazars PKS 0537-441 and PKS 0301-243". The Astronomer's Telegram. 2591: 1. Bibcode:2010ATel.2591....1C.
- ^ Lucarelli, F.; Striani, E.; D'Ammando, F.; Verrecchia, F.; Pittori, C.; Tavani, M.; Vercellone, S.; Del Monte, E.; Donnarumma, I.; Evangelista, Y.; Feroci, M.; Lazzarotto, F.; Pacciani, L.; Soffitta, P.; Costa, E. (2010-02-01). "AGILE detects enhanced gamma-ray emission from the blazar PKS 0537-441". The Astronomer's Telegram. 2454: 1. Bibcode:2010ATel.2454....1L.
- ^ Dolcini, A.; Covino, S.; Treves, A.; Palazzi, E.; Pian, E.; Molinari, E.; Chincarini, G.; Zerbi, F. M.; Rodonó, M.; Testa, V.; Tosti, G.; Vitali, F.; Antonelli, L. A.; Conconi, P.; Cutispoto, G. (2005-11-15). "Multiband photometry of the blazar PKS 0537-441: a major active state in December 2004–March 2005". Astronomy & Astrophysics. 443 (3): L33–L36. doi:10.1051/0004-6361:200500198. ISSN 0004-6361.
- ^ D’Ammando, F.; Antolini, E.; Tosti, G.; Finke, J.; Ciprini, S.; Larsson, S.; Ajello, M.; Covino, S.; Gasparrini, D.; Gurwell, M.; Hauser, M.; Romano, P.; Schinzel, F.; Wagner, S. J.; Impiombato, D. (2013-03-30). "Long-term monitoring of PKS 0537−441 with Fermi–LAT and multiwavelength observations". Monthly Notices of the Royal Astronomical Society. 431 (3): 2481–2492. doi:10.1093/mnras/stt344. ISSN 1365-2966.
- ^ Li, Xiaopan; Zhang, Li; Luo, Yuhui; Wang, Lisha; Zhou, Li (2015-04-02). "Colour variation of the BL Lacertae object PKS 0537–441". Monthly Notices of the Royal Astronomical Society. 449 (3): 2750–2758. doi:10.1093/mnras/stv563. ISSN 1365-2966.
- ^ Shen, Z.Q.; Wan, T.S.; Moran, J.M.; Jauncey, D.L.; Reynolds, J.E.; Tzioumis, A.K.; Gough, R.G.; Ferris, R.H. (April 1998). "A 5 GHz Southern Hemisphere VLBI Survey Of Compact Radio Sources. II". The Astronomical Journal. 115: 1357–1370. doi:10.1086/300284.
- ^ Sandrinelli, A.; Covino, S.; Treves, A. (2016-03-11). "Gamma Ray And Optical Oscillations In PKS 0537–441". The Astrophysical Journal. 820 (1): 20. doi:10.3847/0004-637x/820/1/20. ISSN 0004-637X.
- ^ Heidt, J.; Jäger, K.; Nilsson, K.; Hopp, U.; Fried, J. W.; Sutorius, E. (August 2003). "PKS 0537-441: Extended [O II] emission and a binary QSO?" (PDF). Astronomy & Astrophysics. 406 (2): 565–577. doi:10.1051/0004-6361:20030804. ISSN 0004-6361.