Quenched Galaxies in Clusters of Galaxies and Their Outskirts

Abstract

Based on the SDSS data, the properties of galaxies with quenched star formation (QGs) within the "splashback"-radius of galaxy clusters $R_{\rm sp}$ and beyond it have been studied. We used a sample of 40 groups and galaxy clusters and a sample of field galaxies at $0.02<z<0.045$. The radii $R_{\rm sp}$ were defined from the observed integrated distribution of the number of galaxies as a function of the squared distance from the center of the galaxy systems. We show that in galaxy clusters 72% of the QGs we have found are within $R_{\rm sp}$. About 40% of these galaxies are late-type ones with ${frac}DeV < 0.8$. Approximately 80% of galaxies with quenched star formation have stellar masses in the range of $\log M_*/M_{\odot} = [10; 11]$. We found that QGs of late types and of early types in a less degree have maximum angular radii $R_{90,r}$ and $R_{50,r}$ near the "splashback"-radius of groups and clusters of galaxies. Our results confirm the assumption that in the filaments directed toward clusters, the quenched galaxies are more massive near the boundaries of clusters of galaxies than at the outskirts.