Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-12-14
Astronomy and Astrophysics
Astrophysics
21 pages, 9 Figures, 2 Tables; to appear in ApJ
Scientific paper
10.1086/320458
We have identified a large (~200 kpc), powerful double radio source whose host galaxy is clearly a disk and most likely a spiral. This FR I radio galaxy is located very near the center of the RC 0 cluster Abell 428. The existence of such an object violates a fundamental paradigm for radio loud AGN. In paper I, we showed that this object was most likely a spiral host with optical line ratios and colors consistent with an AGN. In this paper, we present new, higher resolution radio imaging, a radio/mm continuum spectrum for the nucleus, a detection of HI absorption against the bright radio core, an upper-limit to CO and the gas mass, and 70 optical redshifts. We confirm the existence of a radio jet at 20cm extending 42 kpc into the southern lobe. At 3.6cm, we also detect a nuclear jet similar in length to that in M87 but 10 times weaker. We believe that this is the first detection of a radio jet on these scales in a disk or spiral host galaxy. The nuclear radio spectrum is similar to many blazar or QSO like objects, suggesting that the galaxy harbors an imbedded and obscured AGN. We model a turnover in the spectrum at low frequencies as Free-Free absorption. We detect very strong and narrow HI absorption with nearly the entire 20 cm core continuum absorbed, implying an unusually large optical depth (tau~1). We suggest that the nucleus is seen through a disk-like distribution of ISM gas, possibly through a spiral arm or a warp to account for the high column density. From the radial velocities, we find that A428 is in fact made up of at least 2 clumps of galaxies separated by 3300 km/s, which are imbedded in a nearly continuous distribution of galaxies over 13000 km/s in velocity. Thus, the environment resembles a poor group within a filament viewed end-on.
Hill John M.
Ledlow Michael J.
Owen Frazer N.
Yun Min. S.
No associations
LandOfFree
A Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host Properties and External Environment does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host Properties and External Environment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host Properties and External Environment will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-510310