Testing Models of Radio Galaxy Evolution and the Cosmological Impact of FR II Radio Galaxies
Open Access
- 20 March 2007
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 658 (1), 217-231
- https://doi.org/10.1086/511175
Abstract
We investigate aspects of the cosmological evolution of FR II radio galaxies, focusing first on the abilities of models to match data for linear-sizes, radio powers, redshifts and spectral indices. Here we consider modifications to the theoretical models we had treated earlier, primarily by accounting for the growth of the radius of hotspots with source size. Better fits to the distributions of most of the data in three low-frequency surveys can be found with sensible choices of model parameters but no model yet considered gives a good match to all of the survey data simultaneously, nor does any do a good job of producing the spectral index distributions. The observational datasets are too small to completely discriminate among the models. We calculate the volume fraction of the ``relevant universe'' cumulatively occupied by the expanding radio galaxy lobes over the quasar era, when these powerful radio galaxies were much more common, and when they have been argued to play an important role in triggering galaxy formation and spreading magnetic fields and metals. We found the cumulative relevant volume filling factor of radio galaxies to be $sim 5 %$, so we conclude that these impacts are smaller than previously estimated but that they are still significant.Comment: 51 pages in ApJ preprint version, 7 figures, 7 tables. Accepted for publication in The Astrophysical Journa
Keywords
This publication has 69 references indexed in Scilit:
- Testing models of the individual and cosmological evolutions of powerful radio galaxiesMonthly Notices of the Royal Astronomical Society, 2006
- New Corroborative Evidence for the Overdensity of Galaxies around the Radio-Loud Quasar SDSS J0836+0054 at z = 5.8Publications of the Astronomical Society of Japan, 2006
- Discovery of the Low-Energy Cutoff in a Powerful Giant Radio GalaxyThe Astrophysical Journal, 2006
- A Systematic Study of Radio‐induced X‐Ray Cavities in Clusters, Groups, and GalaxiesThe Astrophysical Journal, 2004
- Metallicity of the Intergalactic Medium Using Pixel Statistics. III. SiliconThe Astrophysical Journal, 2004
- The inevitable youthfulness of known high-redshift radio galaxiesNature, 1999
- The Nature and Evolution of Classical Double Radio Sources from Complete SamplesThe Astronomical Journal, 1999
- The FIRST Survey: Faint Images of the Radio Sky at Twenty CentimetersThe Astrophysical Journal, 1995
- Toward Understanding the Fanaroff-Riley Dichotomy in Radio Source Morphology and PowerThe Astrophysical Journal, 1995
- Overpressured cocoons in extragalactic radio sourcesThe Astrophysical Journal, 1989