Flat spectrum radio quasar in the constellation Serpens
NRAO 530 orPKS 1730-13 is aflat-spectrum radio quasar [ 1] constellation ofSerpens . It has aredshift of 0.902.[ 2] [ 3] Hyron Spinrad in 1973.[ 4] blazar because of its optical variability across theelectromagnetic spectrum in radio,gamma ray and X-ray bands.[ 5] OVV quasar .[ 6] [ 7]
Like many other blazars, NRAO 530 is shown to be in a flaring state. In 1994, it showed a striking flare that was observed in radio andmillimeter wavelengths in its 30-year history[ 8] GHz flux.[ 6] X-ray flare was detected in February 2004 byINTEGRAL , with the source being detected in the 20-40keV energy range at the level of ≈2 x 10−10 erg cm−2 s−1 .[ 9] [ 10] [ 11]
NRAO 530 contains a core-jet structure showing detections ofsuperluminal motions in 5 of the jet components with projectedvelocities between the range of 13.6 and 25.2c. Additionally, the structure's compact component (the radio core) is found to be the strongest withpolarized emission around it.[ 12] jet , terminating at a hot spot location. When situated close to the core, the jet abruptly bends, revealing an evolution of aposition angle from north at projectedVLBI scale distance of ~400 parsecs. This is then increased towards west at a larger VLBI scale of ~10kiloparsecs . In the eastern side, a faint and broad counter-jet is seen ending at another bright hot spot creating a diffused lobe.[ 13]
NRAO 530 has two-sidedradio lobes , which the western lobe is found stronger compared to the eastern lobe and is linked to the core.[ 14] [ 12] halo was detected between 1994 and 1995 with an apparent projected velocity of 26 h−1 c.[ 15]
Thesupermassive black hole mass in NRAO 530 is uncertain with some studies estimating it between the ranges of 3 x 108 Mʘ [ 16] 9 Mʘ .[ 17]
^ Jorstad, Svetlana; Wielgus, Maciek; Lico, Rocco; Issaoun, Sara; Broderick, Avery E.; Pesce, Dominic W.; Liu, Jun; Zhao, Guang-Yao; Krichbaum, Thomas P.; Blackburn, Lindy; Chan, Chi-kwan; Janssen, Michael; Ramakrishnan, Venkatessh; Akiyama, Kazunori; Alberdi, Antxon (February 2023)."The Event Horizon Telescope Image of the Quasar NRAO 530" .The Astrophysical Journal .943 (2): 170.arXiv :2302.04622 Bibcode :2023ApJ...943..170J .doi :10.3847/1538-4357/acaea8 ISSN 0004-637X . ^ Junkkarinen, V. (1984-07-01)."Spectrophotometry of the QSO NRAO 530" .Publications of the Astronomical Society of the Pacific .96 :539– 542.Bibcode :1984PASP...96..539J .doi :10.1086/131374 .ISSN 0004-6280 . ^ 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.Bibcode :2005A&A...435..839T .doi :10.1051/0004-6361:20041886 .ISSN 0004-6361 . ^ Welch, W. J.; Spinrad, Hyron (1973-08-01)."High-Frequency Observations of the Radio Source NRAO 530" .Publications of the Astronomical Society of the Pacific .85 (506): 456.Bibcode :1973PASP...85..456W .doi :10.1086/129485 .ISSN 0004-6280 . ^ An, Tao; Baan, Willem A.; Wang, Jun-Yi; Wang, Yu; Hong, Xiao-Yu (2013-08-08)."Periodic radio variabilities in NRAO 530: a jet–disc connection?" .Monthly Notices of the Royal Astronomical Society .434 (4):3487– 3496.doi :10.1093/mnras/stt1265 ISSN 0035-8711 . ^a b Feng, S.-W.; Shen, Z.-Q.; Cai, H.-B.; Chen, X.; Lu, R.-S.; Huang, L. (2006-08-23)."Multi-frequency VLBI observations of NRAO 530" (PDF) .Astronomy & Astrophysics .456 (1):97– 104.arXiv :astro-ph/0605578 Bibcode :2006A&A...456...97F .doi :10.1051/0004-6361:20054678 .ISSN 0004-6361 . ^ Starr, Michelle (2023-02-13)."EHT Peers Into The Heart of One of The Brightest Lights in The Universe" .ScienceAlert . Retrieved2024-10-26 . ^ Bower, Geoffrey C.; Backer, Donald C.; Wright, Melvyn; Forster, James R.; Aller, Hugh D.; Aller, Margo F. (1997-07-20)."A Dramatic Millimeter Wavelength Flare in the Gamma-Ray Blazar NRAO 530" The Astrophysical Journal .484 (1):118– 130.Bibcode :1997ApJ...484..118B .doi :10.1086/304314 .ISSN 0004-637X . ^ Foschini, L.; Pian, E.; Maraschi, L.; Raiteri, C. M.; Tavecchio, F.; Ghisellini, G.; Tosti, G.; Malaguti, G.; Di Cocco, G. (2006-04-01)."A short hard X-ray flare from the blazar NRAO 530 observed by INTEGRAL" .Astronomy and Astrophysics .450 (1):77– 81.arXiv :astro-ph/0601101 Bibcode :2006A&A...450...77F .doi :10.1051/0004-6361:20064804 .ISSN 0004-6361 . ^ D'Ammando, F.; Vandenbroucke, J. (2010-11-01)."Fermi LAT detection of increasing gamma-ray activity from the FSRQ PKS 1730-13" .The Astronomer's Telegram .3002 : 1.Bibcode :2010ATel.3002....1D . ^ Williamson, Karen E.; Jorstad, Svetlana G.; Marscher, Alan P.; Larionov, Valeri M.; Smith, Paul S.; Agudo, Iván; Arkharov, Arkady A.; Blinov, Dmitry A.; Casadio, Carolina; Efimova, Natalia V.; Gómez, José L.; Hagen-Thorn, Vladimir A.; Joshi, Manasvita; Konstantinova, Tatiana S.; Kopatskaya, Evgenia N. (2014-06-23)."Comprehensive Monitoring of Gamma-ray Bright Blazars. I. Statistical Study of Optical, X-ray, and Gamma-ray Spectral Slopes" .The Astrophysical Journal .789 (2): 135.arXiv :1406.2719 Bibcode :2014ApJ...789..135W .doi :10.1088/0004-637x/789/2/135 .ISSN 0004-637X . ^a b Hong, Xiao-Yu; Sun, Chuan-Hao; Zhao, Jun-Hui; Jiang, Dong-Rong; Shen, Zhi-Qiang; An, Tao; Wang, Wei-Hua; Yang, Jun (2008-04-01)."Bending of Jets in the QSO NRAO 530" .Chinese Journal of Astronomy and Astrophysics .8 (2):179– 194.Bibcode :2008ChJAA...8..179H .doi :10.1088/1009-9271/8/2/05 .ISSN 1009-9271 . ^ Zhao, Jun-Hui; Morris, Mark R.; Goss, W. M. (April 2019)."A Procedure for Making High Dynamic-range Radio Images: Deep Imaging of the Kiloparsec-scale Radio Structures of a Distant Blazar, NRAO 530, with JVLA Data" .The Astrophysical Journal .875 (2): 134.arXiv :1903.08586 Bibcode :2019ApJ...875..134Z .doi :10.3847/1538-4357/ab11c4 ISSN 0004-637X . ^ Lu, R.-S.; Krichbaum, T. P.; Zensus, J. A. (2011-11-18)."High-frequency very long baseline interferometry studies of NRAO 530" .Monthly Notices of the Royal Astronomical Society .418 (4):2260– 2272.arXiv :1108.0152 Bibcode :2011MNRAS.418.2260L .doi :10.1111/j.1365-2966.2011.19537.x ISSN 0035-8711 . ^ 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 . ^ Keck, Mason L. (2019-01-01).Probing the inner regions of supermassive black hole accretion disks and jets Bibcode :2019PhDT.......127K . ^ Liang, E. W.; Liu, H. T. (April 2003)."The masses of central supermassive black holes and the variability time-scales in gamma-ray loud blazars" .Monthly Notices of the Royal Astronomical Society .340 (2):632– 638.Bibcode :2003MNRAS.340..632L .doi :10.1046/j.1365-8711.2003.06327.x ISSN 0035-8711 .
