The Signatures of Self-Interacting Dark Matter and Subhalo Disruption on Cluster Substructure

Understand

The abundance, distribution and inner structure of satellites of galaxy clusters can be sensitive probes of the properties of dark matter.

• We run 30 cosmological zoom-in simulations with self-interacting dark matter (SIDM), with a velocity-dependent cross-section, to study the properties of subhalos within cluster-mass hosts.
• We find that the abundance of subhalos that survive in the SIDM simulations are suppressed relative to their cold dark matter (CDM) counterparts.
• Once the population of disrupted subhalos -- which may host orphan galaxies -- are taken into account, satellite galaxy populations in CDM and SIDM models can be reconciled.