3C 49

3C 49
DESI Legacy Surveys image of 3C 49
Observation data (J2000.0 epoch)
ConstellationPisces
Right ascension01h 41m 09.16s
Declination+13° 53′ 28.40″
Redshift0.621000
Heliocentric radial velocity186,171 km/s
Distance6.013 Gly
Apparent magnitude (V)20.92
Apparent magnitude (B)22.32
Characteristics
TypeRadio galaxy HEG
Size~171,000 ly (52.5 kpc) (estimated)
Other designations
4C +13.10, PKS 0138+13, DA 056, OC +164, NRAO 0080, SDSS J014109.16+135328.3, NVSS J014109+135328, PGC 2817501

3C 49 is a radio galaxy located in the constellation of Pisces. The redshift of the object is (z) 0.621, and it was first discovered in the Third Cambridge Catalogue of Radio Sources survey in 1962. The radio spectrum of the galaxy is classified as compact and steep, making it a compact steep spectrum source (CSS).

Description

3C 49 has a complex radio structure. The source is classified as an asymmetric double with two components that are orientated at a 90° position angle and separated by around 0.92 arcseconds, based on observations made with MERLIN. There is a western component and a radio emission bridge of low-surface brightness. At 5 GHz frequencies, a radio core is discovered close to the western component, with the spectral index being 0.14. A radio jet is seen connecting together with a hotspot at the western end. The source's total approximate age is found to be at least 105 years, with its estimated hotspot advanced speed as around 0.05c to 0.1c.

The radio lobes of 3C 49 are irregular. The lobe on the western side is mainly circular with a bright and compact appearance, while the eastern lobe has a fainter appearance with a slight bend degree to the north. Apart from that, the eastern lobe is also depicted as having a steep radio spectrum, while the western lobe spectrum is described as initially flat, gradually steepening upon reaching 610 MHz frequencies.

Observations made with the Very Large Array (VLA) at 15 GHz found 3C 49 has no signs of polarization in both the components located in east and west directions. The host galaxy imaged with the Hubble Space Telescope (HST), is an elliptical galaxy displaying an arc of radio emission towards the western side and beyond the envelope. The total stellar mass of the galaxy is estimated to be 4.5 × 1011 M☉ and it has a stellar population mainly made up of young and intermediate stars. HST imaging also found the host galaxy has a slightly elongated appearance along the radio axis path.

In 3C 49 there are massive ionized outflows. Because of its extremely complicated velocity field, four Gaussian components are required to fit the outflow model. This suggests either the outflow interacting with the surrounding interstellar medium or its radio morphology is three-dimensional. A supermassive black hole mass of 17.6 × 107 M☉ was estimated for the galaxy.

References

  1. 1 2 3 4 5 6 7 "NED Search results for 3C 49". NASA/IPAC Extragalactic Database. Retrieved 2025-10-04.
  2. ↑ Hutchings, J. B.; Neff, S. G.; Weadock, J.; Roberts, L.; Ryneveld, S.; Gower, A. C. (February 1994). "Evolution of Radio Galaxies to z=1". The Astronomical Journal. 107: 471. Bibcode:1994AJ....107..471H. doi:10.1086/116869. ISSN 0004-6256.
  3. ↑ Bennett, A. S. (1962). "The revised 3C catalogue of radio sources". Memoirs of the Royal Astronomical Society. 68: 163. Bibcode:1962MmRAS..68..163B.
  4. ↑ Fanti, C.; Fanti, R.; Parma, P.; Venturi, T.; Schilizzi, R. T.; Rendong, Nan; Spencer, R. E.; Muxlow, T. W. B.; van Breugel, W. (June 1989). "Three prototype compact steep spectrum radio sources". Astronomy and Astrophysics. 217: 44–56. Bibcode:1989A&A...217...44F. ISSN 0004-6361.
  5. ↑ Labiano, A.; Vermeulen, R. C.; Barthel, P. D.; O'Dea, C. P.; Gallimore, J. F.; Baum, S.; Vries, W. de (2006-02-01). "H I absorption in 3C 49 and 3C 268.3 - Probing the environment of compact steep spectrum and GHz peaked spectrum sources" (PDF). Astronomy & Astrophysics. 447 (2): 481–487. doi:10.1051/0004-6361:20053856. ISSN 0004-6361.
  6. ↑ Fanti, C.; Fanti, R.; Parma, P.; Schilizzi, R. T.; van Breugel, W. J. M. (February 1985). "Compact steep spectrum 3 CR radio sources. VLBI observations at 18 cm". Astronomy and Astrophysics. 143: 292–306. Bibcode:1985A&A...143..292F. ISSN 0004-6361.
  7. ↑ Sanghera, H. S.; Saikia, D. J.; Luedke, E.; Spencer, R. E.; Foulsham, P. A.; Akujor, C. E.; Tzioumis, A. K. (March 1995). "High-resolution radio observations of compact steep spectrum sources". Astronomy and Astrophysics. 295: 629. Bibcode:1995A&A...295..629S. ISSN 0004-6361.
  8. ↑ 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" (PDF). 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.
  9. 1 2 3 Best, P. N.; Longair, M. S.; Roettgering, H. J. A. (December 1997). "HST, radio and infrared observations of 28 3CR radio galaxies at redshift z~ - I. The observations". Monthly Notices of the Royal Astronomical Society. 292 (4): 758–794. arXiv:astro-ph/9707337. doi:10.1093/mnras/292.4.758. ISSN 0035-8711.
  10. 1 2 Shih, Hsin-Yi; Stockton, Alan; Kewley, Lisa (2013-07-17). "Ionized Outflows from Compact Steep Spectrum Sources". The Astrophysical Journal. 772 (2): 138. arXiv:1306.5237. Bibcode:2013ApJ...772..138S. doi:10.1088/0004-637x/772/2/138. ISSN 0004-637X.
  11. ↑ Dallacasa, D; Orienti, M; Fanti, C; Fanti, R (2021-04-13). "VLBI images at 327 MHz of compact steep spectrum and GHz-peaked spectrum sources from the 3C and PW samples". Monthly Notices of the Royal Astronomical Society. 504 (2): 2312–2324. arXiv:2104.12804. doi:10.1093/mnras/stab1014. ISSN 0035-8711.
  12. ↑ van Breugel, W. J. M.; Fanti, C. (March 1992). "Compact Steep-Spectrum 3CR sources: VLA observations at 1.5, 15 and 22.5 GHz". Astronomy and Astrophysics. 256: 56–78. Bibcode:1992A&A...256...56V.
  13. ↑ de Vries, W. H.; O'Dea, C. P.; Baum, S. A.; Sparks, W. B.; Biretta, J.; de Koff, S.; Golombek, D.; Lehnert, M. D.; Macchetto, F.; McCarthy, P.; Miley, G. K. (June 1997). "Hubble Space Telescope Imaging of Compact Steep Spectrum Radio Sources". The Astrophysical Journal Supplement Series. 110 (2): 191–211. Bibcode:1997ApJS..110..191D. doi:10.1086/313001. ISSN 0067-0049.
  14. ↑ Best, P. N.; Longair, M. S.; R"ottgering, H. J. A. (1997-09-19), "HST, radio and infrared observations of 28 3CR radio galaxies at redshift z ∼ 1 — II. Old stellar populations in central cluster galaxies", Monthly Notices of the Royal Astronomical Society, 295 (3): 549–567, arXiv:astro-ph/9709195, doi:10.1046/j.1365-8711.1998.01245.x
  15. ↑ Holt, J. (2008-12-15), "The host galaxies of Compact Steep Spectrum and Gigahertz-Peaked Spectrum radio sources", Astronomische Nachrichten, 330 (2–3): 226–232, arXiv:0812.2812, doi:10.1002/asna.200811163
  16. ↑ Westhues, Christian; Haas, Martin; Barthel, Peter; Wilkes, Belinda J.; Willner, S. P.; Kuraszkiewicz, Joanna; Podigachoski, Pece; Leipski, Christian; Meisenheimer, Klaus; Siebenmorgen, Ralf; Chini, Rolf (May 2016). "Star Formation in 3CR Radio Galaxies and Quasars at z < 1". The Astronomical Journal. 151 (5): 120. arXiv:1602.07443. Bibcode:2016AJ....151..120W. doi:10.3847/0004-6256/151/5/120. ISSN 0004-6256.