The Fate of Dwarf Galaxies in Clusters and the Origin of Intracluster Stars. I. Isolated Clusters

TL;DR

This study uses simulations to compare tidal destruction and mergers of dwarf galaxies in clusters, finding mergers dominate but tidal destruction can explain intracluster stars.

Contribution

It introduces a simple simulation algorithm to evaluate the relative importance of tidal destruction versus mergers in dwarf galaxy evolution within clusters.

Findings

Mergers are the primary destruction mechanism for dwarf galaxies.

Tidal destruction alone can account for observed intracluster light.

Simulations support the viability of tidal destruction as a source of intracluster stars.

Abstract

The main goal of this paper is to compare the relative importance of destruction by tides, vs. destruction by mergers, in order to assess if tidal destruction of dwarf galaxies in clusters is a viable scenario for explaining the origin of intracluster stars. We have designed a simple algorithm for simulating the evolution of isolated clusters. The distribution of galaxies in the cluster is evolved using a direct gravitational N-body algorithm combined with a subgrid treatment of physical processes such as mergers, tidal disruption, and galaxy harassment. Using this algorithm, we have performed a total of 227 simulations. Our main results are (1) destruction of dwarf galaxies by mergers dominates over destruction by tides, and (2) the destruction of dwarf galaxies by tides is sufficient to explain the observed intracluster light in clusters.