The Cluster M/L and the Value of Omega_m
Abstract
From an up-to-date compilation of ACO cluster redshifts and velocity dispersions we extract a homogeneous sample of 459 clusters with robust velocity dispersion. Using the virial theorem to estimate cluster masses, and a correlation between Abell galaxy counts and R-band luminosity, we find a median M/L_R of 174 h_50 M_sun/L_sun. However, if we correct the virial masses according to the X-ray vs. virial mass correlation, as derived from our analysis, we obtain M/L_R ~100 h_50 M_sun/L_sun. These two values of M/L imply a mass content of the Universe of Omega_m ~0.26 and 0.15, respectively.
Cite
@article{arxiv.astro-ph/0407098,
title = {The Cluster M/L and the Value of Omega_m},
author = {H. Andernach and M. Plionis and O. L'opez-Cruz and E. Tago and S. Basilakos},
journal= {arXiv preprint arXiv:astro-ph/0407098},
year = {2007}
}
Comments
4 pages, no figures, uses asp2004.sty; to appear in "Nearby Large-Scale Structures and the Zone of Avoidance", eds. A.P. Fairall, P. Woudt, ASP Conf. Series, en prensa, San Francisco: Astronomical Society of the Pacific