Disentangling star formation, environment, and morphology in galaxy evolution

Abstract

Statistical studies of galaxies have matured beyond the calculation of luminosity functions, and by simultaneously analyzing a large number of parameters, such as star formation rates, morphology, and environment, new insights into the mechanisms that drive the evolution of galaxies can be gained. We present a study of the photometric and spectroscopic properties of galaxies in six nearby, rich clusters. The primary issues that we address are: 1) variations of the luminosity function between the field, groups, and clusters, and what this implies for environmental influences, 2) Luminosity Functions for bulges and disks, how they vary with morphology, and what this implies for the mechanisms by which early-type galaxies are formed in dense environments, and 3) whether residual correlations between star formation and environment exist after taking into account the fundamental differences in morphology, stellar mass, and stellar age that already exist between galaxy populations in different environments, and what this implies for the mechanisms that influence star formation.