The Hot Interstellar Medium

TL;DR

This paper reviews the current understanding of the hot interstellar medium in galaxies, focusing on its origins, properties, and role in galaxy evolution through combined theoretical and observational insights.

Contribution

It provides a comprehensive synthesis of recent observational data and theoretical models explaining the hot ISM in different galaxy types.

Findings

Hot ISM is a key diagnostic of galaxy evolution.

Interactions between gravitational, environmental, and feedback processes shape the hot ISM.

Observations and models together enhance understanding of galaxy lifecycle.

Abstract

The interstellar medium (ISM) of galaxies very often contains a gas component that reaches the temperature of several million degrees, whose physical and chemical properties can be investigated through imaging and spectroscopy in the X-rays. We review the current knowledge on the origin and retention of the hot ISM in star-forming and early-type galaxies, from a combined theoretical and observational standpoint. As a complex interplay between gravitational processes, environmental effects, and feedback mechanisms contributes to its physical conditions, the hot ISM represents a key diagnostic of the evolution of galaxies.