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The Cluster M/L and the Value of Omega_m

H. Andernach·M. Plionis·O. L'opez-Cruz·E. Tago·S. Basilakos
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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.

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H. Andernach, M. Plionis, O. L'opez-Cruz, E. Tago, S. Basilakos. 2004-07-05. The Cluster M/L and the Value of Omega_m. https://arxiv.org/abs/astro-ph/0407098

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