Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-11-13
Astronomy and Astrophysics
Astrophysics
Accepted for publication in the Astronomical Journal
Scientific paper
10.1086/323913
Deep optical images have been gathered for a nearly complete sample of radio galaxies from the Revised 3rd Cambridge (3CR) Catalog in the redshift range 0.15 < z < 0.65. Total and nuclear magnitudes and colors have been extracted. The richness of the galaxy clustering environment has also been quantified by calculating the amplitude of the galaxy-galaxy spatial covariance function (B_gg), showing overdensities ranging up to Abell class 0-1 clusters. These optical data are compared to similar data from an existing sample of radio-loud quasars in the same redshift range for the purpose of determining the relationship between radio galaxies and quasars. In the range 0.15 < z < 0.4, we find that quasars and radio galaxies have significantly different environments in that only radio galaxies are found in rich cluster environments. This comparison appears to rule out the hypothesis that all quasars are radio galaxies viewed from a particular angle at the 97% confidence level (99.6% confidence level if N-galaxies are considered quasars). The existence of quasars in clusters at z > 0.4 supports the hypothesis that some radio-loud quasars may dim with time and evolve into radio galaxies with an e-folding time of ~0.9 Gyr. A compatible scenario is presented for this evolution in which the quasar dims due to the absence of low velocity interactions between the quasar host and companion galaxies which trigger quasar activity and/or a diminishing fuel supply caused by the more effective gas ``sweeping'' of a growing intracluster medium.
Ellingson Erica E.
Harvanek Michael
Stocke John T.
No associations
LandOfFree
A Study of 3CR Radio Galaxies from z = 0.15 to 0.65. I. Evidence for an Evolutionary Relationship Between Quasars and Radio Galaxies 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 Study of 3CR Radio Galaxies from z = 0.15 to 0.65. I. Evidence for an Evolutionary Relationship Between Quasars and Radio Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Study of 3CR Radio Galaxies from z = 0.15 to 0.65. I. Evidence for an Evolutionary Relationship Between Quasars and Radio Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-631916