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arXiv · astro-ph/9704060

The CNOC Cluster Survey: Omega, sigma_8, Phi(L,z) Results, and Prospects for Lambda Measurement

Abstract

Rich galaxy clusters are powerful probes of both cosmological and galaxy evolution parameters. The CNOC cluster survey was primarily designed to distinguish between Omega=1 and Omega~0.2 cosmologies. Projected foreground and background galaxies provide a field sample of comparable size. The results strongly support a low-density universe. The luminous cluster galaxies are about 10-30% fainter, depending on color, than the comparable field galaxies, but otherwise they show a slow and nearly parallel evolution. On the average, there is no excess star formation when galaxies fall into clusters. These data provide the basis for a simple Lambda measurement using the survey's clusters and the field data. The errors in Omega_M, Lambda, sigma_8 and galaxy evolution parameters could be reduced to a few percent with a sample of a few hundred clusters spread over the 0<z<1 range.

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R. G. Carlberg, H. K. C. Yee, H. Lin, C. W. Shepherd, P. Gravel, E. Ellingson, S. L. Morris, D. Schade, J. E. Hesser, J. B. Hutchings, J. B. Oke, R. Abraham, M. Balogh, G. Wirth, F. D. A. Hartwick, C. J. Pritchet, T. Smecker-Hane. 1997-04-08. The CNOC Cluster Survey: Omega, sigma_8, Phi(L,z) Results, and Prospects for Lambda Measurement. https://arxiv.org/abs/astro-ph/9704060

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