Properties of Simulated Compact Groups of Galaxies
Abstract
We analyze compact groups of galaxies appearing in a galaxy formation simulation dominated by cold dark matter (omega_0=1, omega_{baryon}=0.1). The simulation uses an N-body code to model the behavior of the non-baryonic matter and smoothed particle hydrodynamics to model the baryons. One run includes gas dynamics alone, and the other incorporates star formation as well. Groups identified as physically compact at z=0 form originally along filaments and become compact in the final ~20% of the simulation; they contain x-ray--luminous diffuse gas well before becoming compact. The component masses, baryon fractions, and gas-to-galaxy mass fractions of the simulated groups are roughly similar somewhat more gas-rich and have x-ray temperatures a factor of 3 lower than those seen in HCGs. These discrepancies may be alleviated by adding the effects of energy input into the diffuse group gas by star formation and supernovae.
Cite
@article{arxiv.astro-ph/9604145,
title = {Properties of Simulated Compact Groups of Galaxies},
author = {Rachel A. Pildis and August E. Evrard and Joel N. Bregman},
journal= {arXiv preprint arXiv:astro-ph/9604145},
year = {2009}
}
Comments
to appear in AJ in August 1996; 32 pages using AASTeX 4.0 macros; paper with full-resolution figures available at http://hea-www.harvard.edu/~pildis/sims.html