| UGC 5101 | |
|---|---|
UGC 5101 by the Hubble Space Telescope
| |
| Observation data (J2000 epoch) | |
| Constellation | Ursa Major |
| Right ascension | 09h35m 51.6s[1] |
| Declination | +61° 21′ 11″[1] |
| Redshift | 0.039367 ± 0.000007 [1] |
| Heliocentric radial velocity | 11,802 ± 2 km/s[1] |
| Distance | 528 Mly (162 Mpc)[1] |
| Apparent magnitude (V) | 15.1 |
| Characteristics | |
| Type | S? [1] |
| Apparent size (V) | 0.83′ × 0.45′[1] |
| Notable features | Ultraluminous infrared galaxy |
| Other designations | |
| MCG +10-14-025, IRAS 09320+6134, PGC 27292[1] | |
UGC 5101 is a galaxy merger located in the constellation Ursa Major. It is located at a distance of about 530 million light years from Earth. It is an ultraluminous infrared galaxy.[1] The total infrared luminosity of the galaxy is estimated to be 1011.95 L☉ and the galaxy has a total star formation rate of 105 M☉ per year.[2]
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 1.3×1024cm−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]
