Compact group

A compact group is a galaxy cluster with galaxies in such close proximity to each other they interact gravitationally and may share material.

Compact groups are associations of a few galaxies in which the environment plays an important role in galaxy evolution.

Studies indicate an evolutionary sequence for compact groups in which the amount of diffuse light increases with the dynamical evolution of the group. The low group velocity dispersion favors tidal interactions and mergers, which may bring stars from galaxies to the diffuse intragroup light. Numerical simulations of galaxy clusters in hierarchical cosmologies show that the amount of the diffuse light increases with the dynamical evolution of the cluster.