Disk dynamics and the X-ray emission of S0 and flat early-type galaxies

TL;DR

This study uses 2D hydrodynamical simulations to explore how galaxy rotation influences the thermal state and X-ray emission of hot gas in early-type galaxies, revealing rotation's role in thermal stability and luminosity.

Contribution

It introduces detailed simulations of hot gas dynamics in early-type galaxies considering various rotational support scenarios, including counter rotation, to understand their impact on ISM properties.

Findings

Rotational support increases susceptibility to thermal instabilities.

Rotating models have lower ISM temperature and X-ray luminosity.

Counter rotating models show intermediate behavior.

Abstract

With 2D hydrodynamical simulations, we study the evolution of the hot gas flows in early-type galaxies, focussing on the effects of galaxy rotation on the thermal and dynamical status of the ISM. The galaxy is modelled as a two-component axisymmetric system (stars and dark matter), with a variable amount of azimuthal velocity dispersion and rotational support; the presence of a counter rotating stellar disk is also considered. It is found that the ISM of the rotationally supported (isotropic) model is more prone to thermal instabilities than the fully velocity dispersion counterpart, while its ISM temperature and X-ray luminosity are lower. The model with counter rotation shows an intermediate behaviour.