NGC 5506

NGC 5506
NGC 5506 by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationVirgo
Right ascension14h 13m 14.9s[1]
Declination−03° 12′ 27″[1]
Redshift0.006084 ± 0.000009 [1]
Heliocentric radial velocity1,824 ± 3 km/s[1]
Distance77 ± 15 Mly (23.6 ± 4.6 Mpc)[1]
Apparent magnitude (V)11.9
Characteristics
TypeSa pec sp [1]
Apparent size (V)3.16′ × 0.75′[1]
Notable featuresSeyfert galaxy
Other designations
UGCΑ 387, MRK 1376, MCG +00-36-028, PGC 50782[1]

NGC 5506 is a spiral galaxy located in the constellation Virgo. It is located at a distance of about 75 million light years from Earth, which, given its apparent dimensions, means that NGC 5506 is about 80,000 light years across.[1] It was discovered by William Herschel on April 15, 1787.[2] It is a Seyfert galaxy.[1]

Characteristics

NGC 5506 is a spiral galaxy seen edge-on, with dust lanes visible south of the nucleus.[3]

Active nucleus

The nucleus of NGC 5506 has been found to be active and it has been categorised as a narrow line type I Seyfert galaxy, and is the brightest such nucleus.[4] The classification of the active nucleus had been an issue of debate, as it lacked broad emission lines in the visual wavelength. However, broader lines were observed in the infrared,[5] indicating that the broad line region is obscured in visual light.[4]

The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The mass of the black hole in the centre of NGC 5506 is estimated to be 8.8×107 M☉ based on stellar velocity dispersion and 5.1×106 M☉ based on the MBH–σ⋆ relation and X-ray variability.[6]

NGC 5506 is a bright X-ray source, detected by all X-ray space observatories, starting with Uhuru.[7] The X-ray spectrum indicates that there is both a compton-thick and a compton-thin absorber. The compton-thick absorber is a dust torus around the supermassive black hole at a distance of around one parsec, while the compton thin absorbs the softer X-rays emitted by the nucleus.[7] The soft emission by the nucleus extends to a distance of about 350 pc and is attributed to reflection of the nuclear emission by photoionized gas.[7] The inclination of the accretion disk is estimated to be between 40° and 50°.[8] The iron line is complex, indicating emission by neutral and ionised iron.[9] A broad component of the Fe Kα fluorescent emission line was observed by XMM-Newton.[10]

The galaxy also emits radiowaves. The galaxy exhibits a central source that accounts for 75% of the total emission and diffuse wing-like emission towards the north-west and east of the nucleus and a low-surface-brightness halo measuring 2.75 arcseconds in diameter that surrounds these features.[11] The features have no clear axis of symmetry.[12] The galaxy has been found to host an H2O megamaser.[13]

Nearby galaxies

NGC 5506 is the foremost galaxy in a galaxy group known as the NGC 5506 Group. Other members of the group include NGC 5507, while IC 978 lies a bit farther away.[14] Garcia identified as members of group also the galaxies NGC 5496, and UGC 9057.[15] NGC 5506 forms a pair with NGC 5507, which lies 4 arcminutes from it.[16] The group is part of the Virgo III Groups, a very obvious chain of galaxy groups on the left side of the Virgo cluster, stretching across 40 million light years of space.[17]

References

  1. ^ a b c d e f g h i j "NASA/IPAC Extragalactic Database". Results for NGC 5506. Retrieved 2023-05-06.
  2. ^ Seligman, Courtney. "NGC 5506". Celestial Atlas. Retrieved 19 November 2018.
  3. ^ Martini, Paul; Regan, Michael W.; Mulchaey, John S.; Pogge, Richard W. (June 2003). "Circumnuclear Dust in Nearby Active and Inactive Galaxies. I. Data". The Astrophysical Journal Supplement Series. 146 (2): 353–406. doi:10.1086/367817.
  4. ^ a b Nagar, N. M.; Oliva, E.; Marconi, A.; Maiolino, R. (August 2002). "NGC 5506 unmasked as a Narrow Line Seyfert 1:: A direct view of the broad line region using near-IR spectroscopy". Astronomy & Astrophysics. 391 (2): L21–L24. doi:10.1051/0004-6361:20021039.
  5. ^ Goodrich, Robert W.; Veilleux, Sylvain; Hill, Gary J. (February 1994). "Infrared spectroscopy of Seyfert 2 galaxies: A look through the obscuring Torus?". The Astrophysical Journal. 422: 521. doi:10.1086/173746.
  6. ^ Nikołajuk, M.; Czerny, B.; Gurynowicz, P. (21 April 2009). "NLS1 galaxies and estimation of their central black hole masses from the X-ray excess variance method". Monthly Notices of the Royal Astronomical Society. 394 (4): 2141–2152. arXiv:0901.1442. doi:10.1111/j.1365-2966.2009.14478.x.
  7. ^ a b c Bianchi, S.; Balestra, I.; Matt, G.; Guainazzi, M.; Perola, G. C. (April 2003). "The recent X–ray history of NGC 5506". Astronomy & Astrophysics. 402 (1): 141–149. doi:10.1051/0004-6361:20030210.
  8. ^ Sun, Shangyu; Guainazzi, Matteo; Ni, Qingling; Wang, Jingchun; Qian, Chenyang; Shi, Fangzheng; Wang, Yu; Bambi, Cosimo (1 August 2018). "Multi-epoch analysis of the X-ray spectrum of the active galactic nucleus in NGC 5506". Monthly Notices of the Royal Astronomical Society. 478 (2): 1900–1910. arXiv:1704.03716. doi:10.1093/mnras/sty1233.
  9. ^ Matt, G.; Guainazzi, M.; Perola, G. C.; Fiore, F.; Nicastro, F.; Cappi, M.; Piro, L. (October 2001). "The complex iron line of NGC 5506". Astronomy & Astrophysics. 377 (3): L31–L34. doi:10.1051/0004-6361:20011209.
  10. ^ Guainazzi, M.; Bianchi, S.; Matt, G.; Dadina, M.; Kaastra, J.; Malzac, J.; Risaliti, G. (June 2010). "Final verdict from XMM-Newton: the X-ray obscured Seyfert galaxy NGC 5506 has a broad Fe Kα line: Broad Kα Fe line in NGC 5506". Monthly Notices of the Royal Astronomical Society: no. arXiv:1004.1442. doi:10.1111/j.1365-2966.2010.16805.x.
  11. ^ Orienti, M.; Prieto, M. A. (1 February 2010). "Radio structures of the nuclei of nearby Seyfert galaxies and the nature of the missing diffuse emission". Monthly Notices of the Royal Astronomical Society. 401 (4): 2599–2610. arXiv:0911.0852. doi:10.1111/j.1365-2966.2009.15837.x.
  12. ^ Middelberg, E.; Roy, A. L.; Nagar, N. M.; Krichbaum, T. P.; Norris, R. P.; Wilson, A. S.; Falcke, H.; Colbert, E. J. M.; Witzel, A.; Fricke, K. J. (April 2004). "Motion and properties of nuclear radio components in Seyfert galaxies seen with VLBI". Astronomy & Astrophysics. 417 (3): 925–944. doi:10.1051/0004-6361:20040019.
  13. ^ Braatz, J. A.; Wilson, A. S.; Henkel, C. (December 1994). "The discovery of five new H2O megamasers in active galaxies". The Astrophysical Journal. 437: L99. doi:10.1086/187692.
  14. ^ Makarov, Dmitry; Karachentsev, Igor (21 April 2011). "Galaxy groups and clouds in the local (z~ 0.01) Universe". Monthly Notices of the Royal Astronomical Society. 412 (4): 2498–2520. arXiv:1011.6277. Bibcode:2011MNRAS.412.2498M. doi:10.1111/j.1365-2966.2010.18071.x. S2CID 119194025.
  15. ^ Garcia, A. M. (1 July 1993). "General study of group membership. II. Determination of nearby groups". Astronomy and Astrophysics Supplement Series. 100: 47–90. Bibcode:1993A&AS..100...47G. ISSN 0365-0138.
  16. ^ de Vaucouleurs, G.; de Vaucouleurs, A.; Corwin, J. R. (1 January 1976). "Second reference catalogue of bright galaxies". Second Reference Catalogue of Bright Galaxies. 1976. Bibcode:1976RC2...C......0D.
  17. ^ "The Virgo III Groups". www.atlasoftheuniverse.com. Retrieved 9 January 2019.
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