On the relationship between environment and galaxy properties in clusters of galaxies

TL;DR

This study investigates how galaxy properties in clusters relate to their environment, finding that galaxy colors are more influenced by cluster-centric distance than by cluster mass, across different cluster samples.

Contribution

It demonstrates that galaxy properties are primarily correlated with cluster-centric distance rather than cluster mass in massive clusters, using SDSS data and a novel analysis technique.

Findings

Galaxy properties do not depend strongly on cluster mass for M > 10^{14} M_sun.

Galaxy colors, especially g-r and u-r, correlate with cluster-centric distance.

The environment predictor is consistent across different cluster selection methods.

Abstract

We study the correlation between different properties of bright (L>L*) galaxies in clusters and the environment in the Sloan Digital Sky Survey (SDSS). Samples of clusters of galaxies used in this paper are those selected by Coenda & Muriel that are drawn from the Popesso et al. and Koester et al. samples. Galaxies in these clusters have been identified in the Main Galaxy Sample of the Fifth Data Release (DR5) of SDSS. We analyse which galaxy properties correlate best with either, cluster mass or cluster-centric distance using the technique by Blanton et al. We find that galaxy properties do not clearly depend on cluster mass for clusters more massive than M~10^{14}M_sun. On the other hand, galaxy properties correlate with cluster-centric distance. The property most affected by the cluster-centric distance is g-r colour, closely followed by the u-r colour. These results are irrespective of the cluster selection criteria. The two samples of clusters were identified based on the X-ray emission and the galaxy colours, respectively. Moreover, the parameter that best predicts environment (i.e. cluster-centric distance) is the same found by Martinez & Muriel for groups of galaxies and Blanton at al. for the local density of field galaxies.