The chemical enrichment of the ICM from hydrodynamical simulations

TL;DR

This paper reviews hydrodynamical simulations and other models of the chemical enrichment of the intra-cluster medium, highlighting recent successes and open questions in understanding cosmic baryon evolution.

Contribution

It provides a comprehensive overview of modeling approaches for ICM enrichment, emphasizing the role of chemo-dynamical models and recent observational comparisons.

Findings

Recent models reproduce key features of ICM metal content.

Hydrodynamical simulations align with X-ray observations.

Open questions remain in modeling feedback processes.

Abstract

The study of the metal enrichment of the intra-cluster and inter-galactic media (ICM and IGM) represents a direct means to reconstruct the past history of star formation, the role of feedback processes and the gas-dynamical processes which determine the evolution of the cosmic baryons. In this paper we review the approaches that have been followed so far to model the enrichment of the ICM in a cosmological context. While our presentation will be focused on the role played by hydrodynamical simulations, we will also discuss other approaches based on semi-analytical models of galaxy formation, also critically discussing pros and cons of the different methods. We will first review the concept of the model of chemical evolution to be implemented in any chemo-dynamical description. We will emphasise how the predictions of this model critically depend on the choice of the stellar initial mass function, on the stellar life-times and on the stellar yields. We will then overview the comparisons presented so far between X-ray observations of the ICM enrichment and model predictions. We will show how the most recent chemo-dynamical models are able to capture the basic features of the observed metal content of the ICM and its evolution. We will conclude by highlighting the open questions in this study and the direction of improvements for cosmological chemo-dynamical models of the next generation.