Radio AGN in 13,240 galaxy clusters from the Sloan Digital Sky Survey

Steve Croft, Wim de Vries, and Robert H. Becker

The Astrophysical Journal, Vol. 667, Issue 1, pp. L13-L16

We have correlated the positions of 13,240 Brightest Cluster Galaxies (BCGs) with redshifts between 0.1 and 0.3 from the maxBCG catalog with radio sources from the FIRST survey to study the sizes and distributions of radio AGN in galaxy clusters. We find that 19.7% of our BCGs are associated with FIRST sources, and this fraction depends on the stellar mass of the BCG, and to a lesser extent on the richness of the parent cluster (in the sense of increasing radio loudness with increasing mass). The intrinsic size of the radio emission associated with the BCGs peaks at 55 kpc, with a tail extending to 200 kpc. The radio power of the extended sources places them on the divide between FR I and FR II type sources, while sources compact in the radio tend to be somewhat less radio-luminous. We also detect an excess of radio sources associated with the cluster, instead of with the BCG itself, extending out to approximately 1.4 Mpc.

Our Astrophysical Journal Letters paper on this work is available here. Please cite this paper if you make use of this work.

Here we provide a 2 MB text file containing our catalog of BCGs matched to the FIRST survey. This text file lists all 13,823 BCGs from the maxBCG sample, along with the RA, Dec, photometric redshift etc. as tabulated by Koester et al. (2007). Column 1 lists the J2000 ID of the BCG, columns 2 - 11 the maxBCG information from Koester et al., columns 12 - 19 the position, flux densities, deconvolved major and minor axes and position angle as listed in the FIRST catalog. Column 20 gives the distance in arcseconds from the BCG position (columns 2 and 3) to the closest FIRST position (columns 12 and 13). In this version of the table, BCGs with no FIRST source closer than 600 arcseconds have the value 99999.99 in column 20, and zeroes in columnns 12 - 19. Column 21 gives the luminosity distance in Mpc at the photometric redshift of the BCG (from column 4).

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©2007 Steve Croft
Last updated: November 6, 2007