ISM Simulations: An Overview of Models

TL;DR

This paper reviews models of the interstellar medium (ISM), emphasizing the transition from equilibrium assumptions to multi-fluid simulations that incorporate thermal and dynamical evolution for more accurate representations.

Contribution

It introduces a multi-fluid modeling approach that accounts for the coupled thermal and dynamical processes in the ISM, advancing beyond previous equilibrium-based simulations.

Findings

Multi-fluid models better capture ISM dynamics.

Non-equilibrium conditions significantly affect ISM evolution.

Enhanced simulation accuracy over traditional CIE assumptions.

Abstract

Until recently the dynamical evolution of the interstellar medium (ISM) was simulated using collisional ionization equilibrium (CIE) conditions. However, the ISM is a dynamical system, in which the plasma is naturally driven out of equilibrium due to atomic and dynamic processes operating on different timescales. A step forward in the field comprises a multi-fluid approach taking into account the joint thermal and dynamical evolutions of the ISM gas.