Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2011-07-26
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
11 pages, 5 figures, 2 tables. Accepted by Astronomy & Astrophysics
Scientific paper
[Abridged] Narrow-line Seyfert 1 (NLS1) galaxies are a class of active galactic nuclei (AGN) that have all the properties of type 1 Seyfert galaxies but show peculiar characteristics, including the narrowest Balmer lines, strongest Fe II emission, and extreme properties in the X-rays. Line and continuum radio observations provide an optimal tool to access the (often) optically obscured innermost regions of AGN and reveal the kinematics of the gas around their central engines. We investigate the interplay between the peculiar NLS1 class of AGN and the maser phenomenon, to help us understand the nature of the maser emission in some NLS1s where water maser emission has been detected. We observed a sample of NLS1 galaxies with the Green Bank Telescope in a search for water maser emission at 22 GHz. We also reduced and analysed archival Green Bank Telescope and Very Large Array data and produced 22-GHz spectra for the five NLS1 galaxies with detected maser emission. In particular, we imaged the maser and nuclear radio continuum of NGC5506 at subarcsec scales with the Very Large Array. We discovered maser emission in two NLS1 galaxies: IGRJ16385-2057, and IRAS03450+0055. In addition to the three previously known maser detections in the NLS1s Mrk766, NGC4051, and NGC5506, this yields a water maser detection rate in NLS1 galaxies of ~7% (5/71). This value rises significantly to ~21% (5/24) when considering only NLS1 galaxies at recessional velocities less than 10000 km/s. For NGC4051 and NGC5506, we find that the water maser emission is located within 5 and 12 pc, respectively, of nuclear radio continuum knots, which are interpreted as core-jet structures.
Braatz James A.
Castangia Paola
Columbano A.
Panessa Francesca
Tarchi Andrea
No associations
LandOfFree
Narrow-line Seyfert 1 galaxies: an amasing class of AGN 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 Narrow-line Seyfert 1 galaxies: an amasing class of AGN, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Narrow-line Seyfert 1 galaxies: an amasing class of AGN will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-93307