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

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
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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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