Kiloparsec-Scale Jets in Three Radio-Loud Narrow-Line Seyfert 1 Galaxies
Abstract
We have discovered kiloparsec-scale extended radio emission in three narrow-line Seyfert 1 galaxies (NLS1s) in sub-arcsecond resolution 9 GHz images from the Karl G. Jansky Very Large Array. We find all sources show two-sided, mildly core-dominated jet structures with diffuse lobes dominated by termination hotspots. These span 20-70 kpc with morphologies reminiscent of FR II radio galaxies, while the extended radio luminosities are intermediate between FR I and FR II sources. In two cases the structure is linear, while a 45° bend is apparent in the third. Very Long Baseline Array images at 7.6 GHz reveal parsec-scale jet structures, in two cases with extended structure aligned with the inner regions of the kiloparsec-scale jets. Based on this alignment, the ratio of the radio core-luminosity to the optical luminosity, the jet/counter-jet intensity and extension length ratios, and moderate core brightness temperatures (≲1010 K), we conclude these jets are mildly relativistic (β ≲ 0.3, δ ∼ 1-1.5) and aligned at moderately small angles to the line of sight (10-15°). The derived kinematic ages of ∼ {{10}6}-107 yr are much younger than radio galaxies but comparable to other NLS1s. Our results increase the number of radio-loud NLS1s with known kiloparsec-scale extensions from 7 to 10 and suggest that such extended emission may be common, at least among the brightest of these sources.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 2015
- DOI:
- 10.1088/2041-8205/800/1/L8
- arXiv:
- arXiv:1501.05299
- Bibcode:
- 2015ApJ...800L...8R
- Keywords:
-
- galaxies: active;
- galaxies: individual: J0953+2836;
- J1435+3131;
- J1722+5654;
- galaxies: jets;
- galaxies: Seyfert;
- radio continuum: galaxies;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 5 pages, 3 figures, 2 tables, accepted to ApJ Letters