Markarian 478

Markarian 478
SDSS image of Seyfert galaxy Markarian 478
Observation data (J2000.0 epoch)
ConstellationBoötes
Right ascension14h 42m 07.47s[1]
Declination+35° 26′ 22.95″[1]
Redshift0.079055[1]
Heliocentric radial velocity23,700 km/s[1]
Distance1.08 Gly
Apparent magnitude (V)14.58
Characteristics
TypeSpiral Sy1[1]
Size~137,000 ly (42.1 kpc) (estimated)[1]
Other designations
PG 1440+356, IRAS 14400+3539, PGC 52510, CG 0512, RBS 1418, RX J1442.1+3526, NVSS J144207+352624[1]

Markarian 478 also known as MRK 478, is a Seyfert 1 galaxy[2] located in the constellation of Boötes. The redshift of the galaxy is (z) 0.079,[1] giving it a distance of about 1 billion light-years from Earth. It was first discovered in 1974 by astronomers from Arecibo Observatory via a 1000-foot radio telescope.[3] It displays doubly ionized iron emission lines in its spectrum and is classified as a radio-quiet quasar.[4][5]

Description

Markarian 478 is specifically described as a prototype narrow-line Seyfert galaxy. It displays emission lines that are increasing in flux levels in blue wing components with increasing line peaks in velocity shifts. The spectrum of this galaxy also shows the presence of absorption lines on the blue wing components of emission doublets and Lyman β lines. Observations also found the high-ionization emission lines have high velocities at blueshifts suggesting outflowing gas is mainly produced in its broad-line region.[6]

The host of Markarian 478 is a round spiral galaxy with two undisturbed asymmetric and visible spiral arms.[5][7] Its nucleus is elongated northeast to southeast, with its main body also being elongated perpendicular to it. Evidence also showed there are faint shells or arms in the host implying a clear disturbed morphology.[8][9] A 3.3-ɥm PAH emission feature was detected in the galaxy.[10]

Markarian 478 is variable. Based on its EUV (Extreme Ultraviolet Emission) light curve, most of the flux variations occurred in the lines and not in continuum. The amplitude variations are described as highly significant, occurring on a factor of three on a timescale less than one day.[11]

The X-ray spectrum of Markarian 478 is soft and steep.[12] It is also mainly dominated by soft excess with some traces of excess residuals in the 5-7 KeV band.[13] Based on observation results using data from Swift, XMM-Newton and AstroSat, it is shown to have both long-term and intermediate-term variability. Evidence also showed the reflection fraction is anticorrelated, with the spectral index and flux suggesting the variability was caused by hard X-rays that were producing a corona moving closer and away from its central black hole.[14] The mass of the black hole in Markarian 478 is estimated to be 7.30 Mʘ.[15]

References

  1. ^ a b c d e f g h "NED search results for Markarian 478". NASA/IPAC Extragalactic Database. Retrieved 2025-08-10.
  2. ^ Gondhalekar, P. M.; Kellett, B. J.; Pounds, K. A.; Matthews, L.; Quenby, J. J. (June 1994). "ROSAT/XRT-PSPC observations and the ionizing continuum of Seyfert 1 galaxy MKN 478". Monthly Notices of the Royal Astronomical Society. 268 (4): 973–983. Bibcode:1994MNRAS.268..973G. doi:10.1093/mnras/268.4.973. ISSN 0035-8711.
  3. ^ Tovmassian, H. M.; Terzian, Y. (October 1974). "Radio Emission from Some Markarian Galaxies at 430 MHz". Publications of the Astronomical Society of the Pacific. 86 (513): 649. Bibcode:1974PASP...86..649T. doi:10.1086/129658. ISSN 0004-6280.
  4. ^ Rudy, Richard J.; Lynch, David K.; Mazuk, S.; Venturini, Catherine C.; Puetter, R. C.; Hamann, F. (August 2001). "Markarian 478: A Second Seyfert Galaxy with 1 Micron Fe II Emission Lines". Publications of the Astronomical Society of the Pacific. 113 (786): 916–919. Bibcode:2001PASP..113..916R. doi:10.1086/322914. ISSN 0004-6280.
  5. ^ a b Dunlop, J. S.; Taylor, G. L.; Hughes, D. H.; Robson, E. I. (September 1993). "Infrared imaging of the host galaxies of radio-loud and radio-quiet quasars". Monthly Notices of the Royal Astronomical Society. 264 (2): 455–488. Bibcode:1993MNRAS.264..455D. doi:10.1093/mnras/264.2.455. ISSN 0035-8711.
  6. ^ Yuan, Q.; Brotherton, M.; Green, R. F.; Kriss, G. A. (June 2004). "Outflowing Components in the Prototype Narrow-Line Seyfert 1 Galaxy Markarian 478". Recycling Intergalactic and Interstellar Matter. 217: 364. Bibcode:2004IAUS..217..364Y. ISSN 1743-9221.
  7. ^ Guyon, O.; Sanders, D. B.; Stockton, Alan (September 2006). "Near-Infrared Adaptive Optics Imaging of QSO Host Galaxies". The Astrophysical Journal Supplement Series. 166 (1): 89–127. arXiv:astro-ph/0605079. Bibcode:2006ApJS..166...89G. doi:10.1086/505030. ISSN 0067-0049.
  8. ^ Surace, Jason A.; Sanders, D. B.; Evans, A. S. (December 2001). "Optical and Near-Infrared Imaging of Infrared-Excess Palomar-Green Quasars". The Astronomical Journal. 122 (6): 2791–2809. arXiv:astro-ph/0109405. Bibcode:2001AJ....122.2791S. doi:10.1086/324462. ISSN 0004-6256.
  9. ^ "Markarian 478". Frankfurt Quasar Monitoring. Retrieved 2025-08-10.
  10. ^ Rodriguez-Ardila, A.; Viegas, S. M. (2003-04-21). "Hidden starbursts in Seyfert 1 galaxies". Monthly Notices of the Royal Astronomical Society. 340 (4): L33 – L37. arXiv:astro-ph/0302327. Bibcode:2003MNRAS.340L..33R. doi:10.1046/j.1365-8711.2003.06538.x. ISSN 0035-8711.
  11. ^ Hwang, Chorng-Yuan; Bowyer, Stuart (February 1997). "The Extreme-Ultraviolet Emission of the Seyfert Galaxies Markarian 279, Markarian 478, and Ton S180". The Astrophysical Journal. 475 (2): 552–556. Bibcode:1997ApJ...475..552H. doi:10.1086/303562. ISSN 0004-637X.
  12. ^ Marshall, H. L.; Carone, T. E.; Shull, J. Michael; Malkan, M. A.; Elvis, M. (January 1996). "The Steep Soft X-Ray Spectrum of the Highly Variable Active Nucleus in Markarian 478". The Astrophysical Journal. 457: 169. Bibcode:1996ApJ...457..169M. doi:10.1086/176720. ISSN 0004-637X.
  13. ^ Waddell, S G H; Gallo, L C; Gonzalez, A G; Tripathi, S; Zoghbi, A (2019-09-10). "Multi-epoch X-ray spectral analysis of the narrow-line Seyfert 1 galaxy Mrk 478". Monthly Notices of the Royal Astronomical Society. 489 (4): 5398–5412. arXiv:1909.01897. doi:10.1093/mnras/stz2518. ISSN 0035-8711.
  14. ^ Barua, Samuzal; Jithesh, V; Misra, Ranjeev; Medhi, Biman J; Adegoke, Oluwashina (2022-09-23). "Correlated variability of the reflection fraction with the X-ray flux and spectral index for Mrk 478". Monthly Notices of the Royal Astronomical Society. 517 (1): 801–807. doi:10.1093/mnras/stac2690. ISSN 0035-8711.
  15. ^ Kawakatu, Nozomu; Imanishi, Masatoshi; Nagao, Tohru (June 2007). "Anticorrelation between the Mass of a Supermassive Black Hole and the Mass Accretion Rate in Type 1 Ultraluminous Infrared Galaxies and Nearby QSOs". The Astrophysical Journal. 661 (2): 660–671. arXiv:astro-ph/0702552. Bibcode:2007ApJ...661..660K. doi:10.1086/516563. ISSN 0004-637X.
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