Simulations of galactic disks including a dark baryonic component

TL;DR

This paper presents N-body simulations of galactic disks with increased gas content, exploring the impact of a substantial unseen baryonic component on disk stability and structure.

Contribution

It introduces a novel simulation approach incorporating a cold, collisionless baryonic phase to account for missing baryons in galactic disks.

Findings

Enhanced gas content affects disk stability.

Two-phase ISM model supports unseen baryons.

Simulation results align with observational hints of massive disks.

Abstract

$\Lambda$CDM numerical simulations predict that the "missing baryons" reside in a Warm-Hot gas phase in the over-dense cosmic filaments. However, there are now several theoretical and observational arguments that support the fact that galactic disks may be more massive than usually thought, containing a substantial fraction of the "missing baryons". Hereafter, we present new N-body simulations of galactic disks, where the gas content has been multiplied by a factor 5. The stability of the disk is ensured by assuming that the ISM is composed out of two partially coupled phases, a warm phase, corresponding the observed CO and HI gas and a cold collisionless phase corresponding to the unseen baryons.