3C 309.1
| 3C 309.1 | |
|---|---|
 The quasar 3C 309.1. | |
| Observation data (J2000.0 epoch) | |
| Constellation | Ursa Minor |
| Right ascension | 14h 59m 07.583s |
| Declination | 71° 40′ 19.867″ |
| Redshift | 0.901113 |
| Heliocentric radial velocity | 270,147 km/s |
| Distance | 7.665 Gly |
| Apparent magnitude (V) | 16.78 |
| Apparent magnitude (B) | 17.24 |
| Characteristics | |
| Type | CSS |
| Other designations | |
| LEDA 2821824, 4C 71.15, WMAP 071, QSO B1458 718, 2E 3367, NRAO 464, 1Jy 1458 718 | |
3C 309.1 is a quasar[1] located in the constellation of Ursa Minor. It has a redshift (z) of 0.90[2] and was first identified as an astronomical radio source from the Third Cambridge Catalogue of Radio Sources by in 1966.[3] This object contains a compact steep spectrum (CSS) source,[4] and is classified as one of the brightest and largest of its kind.[2][5]
Description
[edit]3C 309.1 has a triple radio structure. It has a radio core found self-absorbed with an extended position angle of 162° ± 2°. On both sides of the core, there are two relatively extended outer radio lobes having a defined positional angle of 90°.[6]
In sub-arcsecond resolutions, the structure is made up of several components. Three of them are aligned east–west while the others are located along the path of extended emission in a southern direction, clearly detected by two X-ray images. In two of the brightest components, there is polarized emission.[7] However, when viewed at a 5 GHz milliarcsecond (mas) resolution, a bright core is found instead straddled by two other weaker components with a separation of 8.7 kiloparsecs.[8] Sub-milliarcsecond imaging shows the core to be compact with a more extended component located 20 mas to the south.[9]
The jet of 3C 309.1 is one-sided. It is found to be flaring away from the nucleus with a sharp change in brightness, likely caused through various Kelvin-Helmholtz instabilities in confined fluid flow and pressure being exerted in confined medium.[10] In Very Long Baseline Interferometry radio imaging, the jet is shown to extend from the core southwards with a distance of 260 parsecs (60 mas). At eastwards, it bends at 90° before fading rapidly.[8] Furthermore, the jet is extremely polarized.[11][12]
The host galaxy of 3C 309.1 is a flat elliptical galaxy according to Hubble Space Telescope imaging. It has a major axis orientated along the position angle of 130°.[13] Extensive emission-line gas is also seen surrounding the object at high pressure, with a massive cooling rate exceeding 1000 Mʘ yr−1 implying its host galaxy might have been formed within a Hubble time.[14]
References
[edit]- ^ Simon, R. S. (1983-09-01). "High Resolution Maps of the Quasars 3C48, 3C147, 3C309.1, 3C380, and 3C454.3 Using 90cm VLBI". Bulletin of the American Astronomical Society. 15: 976. Bibcode:1983BAAS...15..976S.
- ^ a b Aaron, Scott E.; Wardle, John F.C.; Roberts, David H. (1998). "A Multi-Frequency VLBI Polarization Study of the CSS Quasar 3C 309.1". International Astronomical Union Colloquium. 164: 105–106. doi:10.1017/s0252921100044729. ISSN 0252-9211.
- ^ Véron, P. (June 1966). "Optical Positions for Radio Sources in the 3c Revised Catalogue". The Astrophysical Journal. 144: 861. Bibcode:1966ApJ...144..861V. doi:10.1086/148682. ISSN 0004-637X.
- ^ Gawronski, Marcin; Kus, Andrzej J. (2007-11-22). "Multi-frequency VSOP and VLBI observations of the quasar 3C309.1" (PDF). Proceedings of 8th European VLBI Network Symposium — PoS(8thEVN). Trieste, Italy: Sissa Medialab: 020. doi:10.22323/1.036.0020.
- ^ "3C 309.1 | Image Gallery | Brandeis Radio Astronomy Group | Brandeis University". www.brandeis.edu. Retrieved 2024-11-17.
- ^ Kus, A. J.; Wilkinson, P. N.; Booth, R. S. (1981-03-01). "The radio structure of 3C 309.1 determined by multi-baseline interferometry". Monthly Notices of the Royal Astronomical Society. 194 (3): 527–535. doi:10.1093/mnras/194.3.527. ISSN 0035-8711.
- ^ Mantovani, F.; Rossetti, A.; Junor, W.; Saikia, D. J.; Salter, C. J. (2013-06-18). "Radio polarimetry of compact steep spectrum sources at sub-arcsecond resolution" (PDF). Astronomy & Astrophysics. 555: A4. arXiv:1305.1644. Bibcode:2013A&A...555A...4M. doi:10.1051/0004-6361/201220769. ISSN 0004-6361.
- ^ a b Pearson, T. J.; Readhead, A. C. S. (May 1988). "The milliarcsecond structure of a complete sample of radio sources. II - First-epoch maps at 5 GHz". The Astrophysical Journal. 328: 114. Bibcode:1988ApJ...328..114P. doi:10.1086/166274. ISSN 0004-637X.
- ^ Zensus, J. A.; Ros, E.; Kellermann, K. I.; Cohen, M. H.; Vermeulen, R. C.; Kadler, M. (August 2002). "Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei. II. Additional Sources". The Astronomical Journal. 124 (2): 662–674. arXiv:astro-ph/0205076. Bibcode:2002AJ....124..662Z. doi:10.1086/341585. ISSN 0004-6256.
- ^ Wilkinson, P.N.; Kus, A.J.; Pearson, T.J.; Readhead, A.C.S.; Cornwell, T.J. (1986). "The Nuclear Jets in 3c 309.1 and 3c 380". International Astronomical Union. 119: 165–166. doi:10.1017/S0074180900152556.
- ^ Akujor, C.E.; Garrington, S.T. (1995). "Compact steep-spectrum sources - polarisation observations at 1.6, 4.9, 8.4 and 15 GHz". Astronomy and Astrophysics Supplement. 112: 235–255. Bibcode:1995A&AS..112..235A.
- ^ Ludke, E.; Garrington, S. T.; Spencer, R. E.; Akujor, C. E.; Muxlow, T. W. B.; Sanghera, H. S.; Fanti, C. (1998-09-01). "MERLIN polarization observations of compact steep-spectrum sources at 5 GHz". Monthly Notices of the Royal Astronomical Society. 299 (2): 467–478. Bibcode:1998MNRAS.299..467L. doi:10.1046/j.1365-8711.1998.01843.x. ISSN 0035-8711.
- ^ Lehnert, Matthew D.; Miley, George K.; Sparks, William B.; Baum, Stefi A.; Biretta, John; Golombek, Daniel; de Koff, Sigrid; Macchetto, Ferdinando D.; McCarthy, Patrick J. (August 1999). "Hubble Space Telescope – Snapshot Survey of 3CR Quasars: The Data". The Astrophysical Journal Supplement Series. 123 (2): 351–376. Bibcode:1999ApJS..123..351L. doi:10.1086/313239. ISSN 0067-0049.
- ^ Forbes, D. A.; Crawford, C. S.; Fabian, A. C.; Johnstone, R. M. (1990-06-01). "Extended emission-line gas around the quasars 3C 254 and 3C 309.1 . Very massive cooling flows". Monthly Notices of the Royal Astronomical Society. 244: 680. Bibcode:1990MNRAS.244..680F. ISSN 0035-8711.
