Simulations of galactic disks including a dark baryonic component

Abstract

$Λ$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.

4 pages, 2 figures. To appear in the proceedings of "Formation and Evolution of Galaxy Disks", ed. J. Funes & E. Corsini. Higher resolution version may be downloaded at https://obswww.unige.ch/~revaz/public/Rome2007/revaz.pdf