Astronomy and Astrophysics – Astrophysics
Scientific paper
1998-11-04
Astronomy and Astrophysics
Astrophysics
accepted for publication in MNRAS, 10 pages; typos/minor correction
Scientific paper
10.1046/j.1365-8711.1999.02234.x
We investigate the correlations between spectral index, jet side and extent of the radio lobes for a sample of nearby FRII radio galaxies. In Dennett-Thorpe et al. (1997) we studied a sample of quasars and found that the high surface brightness regions had flatter spectra on the jet side (explicable as a result of Doppler beaming) whilst the extended regions had spectral asymmetries dependent on lobe length. Unified schemes predict that asymmetries due to beaming will be much smaller in narrow-line radio galaxies than in quasars: we therefore investigate in a similar manner, a sample of radio galaxies with detected jets. We find that spectral asymmetries in these objects are uncorrelated with jet sidedness at all brightness levels, but depend on relative lobe volume. Our results are not in conflict with unified schemes, but suggest that the differences between the two samples are due primarily to power or redshift, rather than to orientation. We also show directly that hotspot spectra steepen as a function of radio power or redshift. Whilst a shift in observed frequency due to the redshift may account for some of the steepening, it cannot account for all of it, and a dependence on radio power is required.
Bridle Alan H.
Dennett-Thorpe Jane
Laing Robert A.
Scheuer P. A. G.
No associations
LandOfFree
Asymmetry of jets, lobe size and spectral index in radio galaxies and quasars 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 Asymmetry of jets, lobe size and spectral index in radio galaxies and quasars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Asymmetry of jets, lobe size and spectral index in radio galaxies and quasars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-610537