UGC 5101 has a single nucleus surrounded by spiral isophotes.[3] The nucleus of UGC 5101 has been found to be active and it has been categorised as a type 1.5 Seyfert galaxy or a LINER based on the radio continuum.[4][5] 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 UGC 5101 is estimated to be 108.2 (160 million) M☉ based on stellar velocity dispersion.[6]
The galaxy also hosts a water megamaser, probably originating from the nucleus.[7]
The nucleus emits hard X-rays, which are strongly absorbed, while there is also a soft X-rays component, which could originate from a hidden starburst region.[8] Also NeV emission has been detected in the nucleus, indicating the presence of a hot gas in the coronal line region, while hot dust has been detected around the nucleus, as indicated by the presence of PAH emission and strong silicate absorption.[9][10][11] The nucleus is surrounded by a dust torus with an opening angle larger than 41° which partly obstructs the nucleus with a column density of NHLS about 1.3×1024 cm−2. The hole of the torus is covered with compton thin material.[12] The integrated intensities of HCN to 13CO indicate the gas in the torus is very dense.[13] When observed with very-long-baseline interferometry the galaxy features a ridgeline that could be compact jets generated by the active nucleus.[14]
The galaxy has a tidal tail, seen edge on, and a faint halo of stars that was created during the merger.[15] A second tidal tail appears to loop around the nucleus, forming a ring.[3]
See also
NGC 6240 and Markarian 273 - two other near ultraluminous infrared galaxies with active nuclei
^ abScoville, N. Z.; Evans, A. S.; Thompson, R.; Rieke, M.; Hines, D. C.; Low, F. J.; Dinshaw, N.; Surace, J. A.; Armus, L. (March 2000). "NICMOS Imaging of Infrared-Luminous Galaxies". The Astronomical Journal. 119 (3): 991–1061. arXiv:astro-ph/9912246. Bibcode:2000AJ....119..991S. doi:10.1086/301248. S2CID14039970.
^Abrahamyan, H. V.; Mickaelian, A. M.; Paronyan, G. M.; Mikayelyan, G. A. (September 2020). "Classification by Activity Type of a Sample of Active Galaxies with Radio Emission". Astrophysics. 63 (3): 322–333. Bibcode:2020Ap.....63..322A. doi:10.1007/s10511-020-09637-0. S2CID225182307.
^Armus, L.; Charmandaris, V.; Bernard-Salas, J.; Spoon, H. W. W.; Marshall, J. A.; Higdon, S. J. U.; Desai, V.; Teplitz, H. I.; Hao, L.; Devost, D.; Brandl, B. R.; Wu, Y.; Sloan, G. C.; Soifer, B. T.; Houck, J. R.; Herter, T. L. (10 February 2007). "Observations of Ultraluminous Infrared Galaxies with the Infrared Spectrograph on the Spitzer Space Telescope . II. The IRAS Bright Galaxy Sample". The Astrophysical Journal. 656 (1): 148–167. arXiv:astro-ph/0610218. Bibcode:2007ApJ...656..148A. doi:10.1086/510107. S2CID25489647.
^Armus, L.; Charmandaris, V.; Spoon, H. W. W.; Houck, J. R.; Soifer, B. T.; Brandl, B. R.; Appleton, P. N.; Teplitz, H. I.; Higdon, S. J. U.; Weedman, D. W.; Devost, D.; Morris, P. W.; Uchida, K. I.; van Cleve, J.; Barry, D. J.; Sloan, G. C.; Grillmair, C. J.; Burgdorf, M. J.; Fajardo-Acosta, S. B.; Ingalls, J. G.; Higdon, J.; Hao, L.; Bernard-Salas, J.; Herter, T.; Troeltzsch, J.; Unruh, B.; Winghart, M. (September 2004). "Observations of Ultraluminous Infrared Galaxies with the Infrared Spectrograph (IRS) on the Spitzer Space Telescope : Early Results on Markarian 1014, Markarian 463, and UGC 5101". The Astrophysical Journal Supplement Series. 154 (1): 178–183. arXiv:astro-ph/0406179. Bibcode:2004ApJS..154..178A. doi:10.1086/422915. S2CID43204883.
^Cruz-González, I; Gómez-Ruiz, A I; Caldú-Primo, A; Benítez, E; Rodríguez-Espinosa, J M; Krongold, Y; Aretxaga, I; Snell, R; González-Martin, O; Negrete, C A; Narayanan, G; Hughes, D H; Yun, M S; Fazio, G G; Chavushyan, V; Hiriart, D; Jiménez-Bailón, E; Herrera-Endoqui, M; Martínez-Paredes, M; González, J J (17 October 2020). "Early science with the LMT: molecular torus in UGC 5101". Monthly Notices of the Royal Astronomical Society. 499 (2): 2042–2050. doi:10.1093/mnras/staa2949.
^Lonsdale, Carol J.; Lonsdale, Colin J.; Smith, Harding E.; Diamond, Philip J. (August 2003). "VLBI Imaging of Luminous Infrared Galaxies: Active Galactic Nucleus Cores in Markarian 231, UGC 5101, and NGC 7469". The Astrophysical Journal. 592 (2): 804–818. arXiv:astro-ph/0304335. Bibcode:2003ApJ...592..804L. doi:10.1086/375778. S2CID14352535.
^"UGC 5101". www.spacetelescope.org. 24 April 2008. Retrieved 19 June 2023.