PG 0844+349
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| PG 0844+349 | |
|---|---|
 PG 0844+349 and its companion galaxy captured by SDSS | |
| Observation data (J2000 epoch) | |
| Constellation | Lynx |
| Right ascension | 08h 47m 42.47s |
| Declination | +34d 45m 04.40s |
| Redshift | 0.064000 |
| Heliocentric radial velocity | 19,187 km/s |
| Distance | 849 Mly (260.3 Mpc) |
| Apparent magnitude (V) | 0.10 |
| Apparent magnitude (B) | 0.13 |
| Surface brightness | 13.5 |
| Characteristics | |
| Type | Sp (d), Sy1, |
| Notable features | Seyfert galaxy containing a quasar |
| Other designations | |
| TON 951, RBS 724, PGC 24702, RX J0847.6+3445, LAMOST J084742.44+344504.4, CSO 204, 2E 2048, 1ES 0844+349, 2PBC J0848.2+3443 | |
PG 0844+349, also known as TON 951 (abbreviation of Tonantzintla 951), is a galaxy in the southern constellation Lynx, near the border of Cancer. Its redshift is 0.064000, putting the galaxy at 849 million light-years away from Earth.[1]
PG 0844+349 was first discovered in 1957 by the Tonantzintla Observatory who was searching for blue stellar objects (mainly white dwarfs) as quasar candidates.[2] Because quasars were not identified until 1963,[3] the nature of this object was unknown. Studying photographic plates that were taken with the 0.7 m Schmidt telescope, it was discovered PG 0844+349 has a Seyfert 1 spectrum, classifying it as a quasar. Mexican astronomers Braulio Iriarte and Enrique Chavira subsequently listed it as the 951st object in the Tonantzintla Catalogue.[4] The same case was applied with TON 618.
In 2009, PG 0844+349 was observed again, by the Swift observatory, and it was noted to have a weak X-ray state. Several weeks later, a follow-up observation by XMM-Newton found it showing a spectral hardening and substantial curvature. This shows that PG 0844+349 is in the phase of reflection-dominated state and its light bending scenario can be accounted for short-term ( ∼1000 s) spectral variability in its source.[5]
Characteristics
PG 0844+349 has an active galactic nucleus. It is classified a Seyfert type 1.0 galaxy,[6] containing two sets of emission lines superimposed onto each other. One set of lines is a low-density (electron density ne 103-106 cm−3) ionized gas that has widths which corresponds to velocities of several hundred kilometers per second. The other is a set of broad lines, with widths as high as 104 km s−1; but the absence of broad forbidden-line emission indicates that the broad-line gas is of high density (ne 109 cm−3 or higher).[7] It can be said PG 0844+349 is a narrow-line Seyfert 1 galaxy considered having all characteristics of type 1 Seyfert galaxies,[8] but it does not have any hardness ratio variations as a single observation finds no strong correlation between the hardness ratio and the continuum luminosity.[9]
PG 0844+349 is also a quasar but with low luminosity.[2] The quasar host is a disturbed face-on barred spiral galaxy,[10][11] which is found interacting with its companion galaxy, 2MASX J08474179+3444405.[12] Both galaxies show signs of gravitational distortion, in which tidal tails and a hot blue stellar component can be seen.[2] Through the interaction with 2MASX J08474179+3444405, this causes the activity in the central region of PG 0844+349 to awaken causing it to create more star formation with its black hole mass suppressed by its increasing starburst luminosity.[13] This gives it its quasar appearance.