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arXiv · astro-ph/9804312

The Omega_M-Omega_Lambda Constraint from CNOC Clusters

R. G. Carlberg·H. K. C. Yee·E. Ellingson·S. L. Morris·H. Lin·M. Sawicki·D. Patton·G. Wirth·R. Abraham·P. Gravel·C. J. Pritchet·T. Smecker-Hane·D. Schade·F. D. A. Hartwick·J. E. Hesser·J. B. Hutchings·J. B. Oke
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Abstract

The CNOC redshift survey of galaxy clusters measures Omega_M from Omega_e(z)= M/L x j/ρ_c which can be applied on a cluster-by-cluster basis. The mass-to-light ratios, M/L, are estimated from rich galaxy clusters, corrected to the field population over the 0.18 to 0.55 redshift range. Since the luminosity density depends on cosmological volumes, the resulting Omega_e(z) has a strong dependence on cosmology which allows us to place the results in the Omega_M-Omega_Lambda plane. The resulting Omega_M declines if Omega_Lambda>0 and we find that Omega_Lambda<1.5.

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R. G. Carlberg, H. K. C. Yee, E. Ellingson, S. L. Morris, H. Lin, M. Sawicki, D. Patton, G. Wirth, R. Abraham, P. Gravel, C. J. Pritchet, T. Smecker-Hane, D. Schade, F. D. A. Hartwick, J. E. Hesser, J. B. Hutchings, J. B. Oke. 1998-04-28. The Omega_M-Omega_Lambda Constraint from CNOC Clusters. https://arxiv.org/abs/astro-ph/9804312

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