PG 1612+261 known alternatively as TON 256 (abbreviation of Tonantzintla 256), is a Seyfert 1 galaxy located in the constellation of Corona Borealis. It is located 1.6 billion light-years away from Earth and was first discovered as a blue quasi-stellar galaxy in 1965.
Description PG 1612+261 is a radio-quiet quasar with a redshift of (z) 0.131. It has a supermassive black hole mass of M☉ and a star formation rate of M☉ yr–1. Its host galaxy is undisturbed based on H band imaging, with a bright central nucleus. Further evidence also showed it has either a normal or slightly reddened appearance.
The spectrum of PG 1612+261 shows evidence of a helium broad emission feature. The source of the object is described having a steep radio spectrum between 5 and 8.5 GHz frequencies. It is also known to show radio outflows but no traces of broadline region wind.
The radio structure of PG 1612+261 can be described as a triple structure that is being aligned in all directions with a compact faint source having a flux density of 0.17 mJy. There is also presence of diffused radio emission with an extension of 3 kiloparsecs. When revealed by a 8.4 GHz mapping by Very Large Array (VLA), the nuclear component is fully resolved into a double source with a one-sided jet found heading towards southwest. Radio imaging by Very Long Baseline Array (VLBA) at 1.4 GHz found it is found elongated by east to west direction while a 1.6 GHz radio image shows there are two components instead, with the western component having a spectral index of = .
An emission narrow-line region is found surrounding PG 1612+261. Based on studies, the region is found dominated by large scale rotation motion. There is a doubly ionized oxygen line profile located close to the nucleus of PG 1612+261 with a line width of km s–1. The radial velocity offset of the line is estimated to be km s–1.
References
External links PG 1612+261 on SIMBAD