Baryon Content of Massive Galaxy Clusters at z=0-0.6

TL;DR

This study investigates how the baryonic components, stars and ionized gas, in galaxy clusters evolve over redshift 0 to 0.6, revealing different evolutionary patterns for these components within cluster cores.

Contribution

It provides a self-consistent analysis of the evolution of stellar and ICM masses in galaxy clusters across redshift, highlighting different evolutionary behaviors.

Findings

ICM mass--total mass relation evolves self-similarly

No redshift evolution in stellar mass--total mass relation

Stellar and ICM components evolve differently in cluster cores

Abstract

We study the relationship between two major baryonic components in galaxy clusters, namely the stars in galaxies, and the ionized gas in the intracluster medium (ICM), using 94 clusters that span the redshift range 0-0.6. Accurately measured total and ICM masses from Chandra observations, and stellar masses derived from the Wide-field Infrared Survey Explorer and the Two-Micron All-Sky Survey allow us to trace the evolution of cluster baryon content in a self-consistent fashion. We find that, within r_{500}, the evolution of the ICM mass--total mass relation is consistent with the expectation of self-similar model, while there is no evidence for redshift evolution in the stellar mass--total mass relation. This suggests that the stellar mass and ICM mass in the inner parts of clusters evolve differently.