NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-22 T07:00:39 PDT
Help | Comment | NED Home

For refcode 2015MNRAS.446.2709E:
Retrieve 157 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by Royal Astronomical Society. 2015MNRAS.446.2709E X-ray bright active galactic nuclei in massive galaxy clusters - III. New insights into the triggering mechanisms of cluster AGN Ehlert, S.; Allen, S. W.; Brandt, W. N.; Canning, R. E. A.; Luo, B.; Mantz, A.; Morris, R. G.; von der Linden, A.; Xue, Y. Q. Abstract. We present the results of a new analysis of the X-ray selected active galactic nuclei (AGN) population residing in and behind 135 of the most massive galaxy clusters in the redshift range of 0.2 < z < 0.9 observed with Chandra. With a sample of more than 11 000 X-ray point sources, we are able to measure, for the first time, evidence for evolution in the cluster AGN population beyond the expected evolution of field AGN. Our analysis shows that overall number density of cluster AGN scales with the cluster mass as ~ M_500_^- 1.2^. There is no evidence for the overall number density of cluster member X-ray AGN depending on the cluster redshift in a manner different than field AGN, nor is there any evidence that the spatial distribution of cluster AGN (given in units of the cluster overdensity radius r_500_) strongly depends on the cluster mass or redshift. The M^-1.2 +/- 0.7^ scaling relation we measure is consistent with theoretical predictions of the galaxy merger rate in clusters, which is expected to scale with the cluster velocity dispersion, sigma, as ~sigma^-3^ or ~M^-1^. This consistency suggests that galaxy mergers may be an important contributor to the cluster AGN population, a result that is further corroborated by visual inspection of Hubble images for 23 spectroscopically confirmed cluster member AGN in our sample. A merger-driven scenario for the triggering of X-ray AGN is not strongly favoured by studies of field galaxies, however, suggesting that different mechanisms may be primarily responsible for the triggering of cluster and field X-ray AGN. Key words: galaxies: active, galaxies: clusters: general, X-rays: galaxies, X-rays: galaxies: clusters
Retrieve 157 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home