Interacting Galaxies in Sparsely Populated Groups

Abstract

We calculated the median values of the following parameters for 87 groups of galaxies with three to eight components: the mean rms velocity of the galaxies in the group, S_v = 166 km/s; the harmonic mean radius, R_h = 29 kpc; and the mass-to-light ratio, M_vir/L = 33 Msun/Lsun. The M_vir/L ratio depends on the population of the system, while S_v does not depend on R_h. To ascertain the relationship between the activity of galaxies in groups and their morphological composition and the effect of the environment on the evolutionary processes in groups, we consider the fraction of galaxies with UV excess in the sample of interacting galaxies in groups (6%), single peculiar galaxies (8%), and isolated galaxies (4%) and their morphological composition. We also show that the number of active galaxies decreases with increasing population of the group of galaxies, while the frequency of occurrence of early-type (E/S0) galaxies increases.