Radio-selected Galaxies in Very Rich Clusters at z < 0.25: I. Multi-wavelength Observations and Data Reduction Techniques

Abstract

Radio observations were used to detect the `active' galaxy population within rich clusters of galaxies in a non-biased manner that is not plagued by dust extinction or the K-correction. We present wide-field radio, optical (imaging and spectroscopy), and ROSAT All-Sky Survey (RASS) X-ray data for a sample of 30 very rich Abell (R > 2) cluster with z < 0.25. The VLA radio data samples the ultra-faint radio (L(1.4 GHz) > 2E22 W/Hz) galaxy population within these extremely rich clusters for galaxies with M_R < -21. This is the largest sample of low luminosity 20 cm radio galaxies within rich Abell clusters collected to date. The radio-selected galaxy sample represents the starburst (Star formation rate > 5 M_sun/yr) and active galactic nuclei (AGN) populations contained within each cluster. Archival and newly acquired redshifts were used to verify cluster membership for most (~95%) of the optical identifications. Thus we can identify all the starbursting galaxies within these clusters, regardless of the level of dust obscuration that would affect these galaxies being identified from their optical signature. Cluster sample selection, observations, and data reduction techniques for all wavelengths are discussed.