The Fate of Gas rich Satellites in Clusters

TL;DR

This paper models how gas-rich satellite galaxies lose stars due to gravitational potential changes caused by ram pressure stripping in clusters, explaining the formation of ultra diffuse galaxies and intracluster light.

Contribution

It introduces a model for stellar mass loss in gas-rich satellites during cluster infall, linking gas stripping to galaxy morphology and intracluster light formation.

Findings

Less-massive satellites experience more significant stellar stripping.

Gas-rich satellites can appear as ultra diffuse galaxies after puffing up.

Stripping contributes to the intracluster light and affects galaxy color distribution.

Abstract

We investigate the stellar mass loss of gas rich galaxies falling into clusters due to the change in the gravitational potential caused by the ram pressure stripping of their gas. We model the satellites with exponential stellar and gas disk profiles, assume rapid ram pressure stripping, and follow the stellar orbits in the shocked potential. Due to the change of the potential, the stars move from circular orbits to elliptical orbits with apocenters that are often outside the tidal radius, causing those stars to be stripped. We explore the impact of the redshift of infall, gas fraction, satellite halo mass and cluster mass on this process. The puffing of the satellites makes them appear as ultra diffuse galaxies, and the stripped stars contribute to the intracluster light. Our results show these effects are most significant for less-massive satellites, which have larger gas fractions when they are accreted into clusters. The preferential destruction of low mass systems causes the red fraction of cluster galaxies to be smaller at lower masses, an observation that is otherwise difficult to explain.