Cluster Evolution in the Wide Angle ROSAT Pointed Survey (WARPS)

C. A. Scharf; L. R. Jones; E. Perlman; H. Ebeling; G. Wegner; M. Malkan; D. Horner

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Cluster Evolution in the Wide Angle ROSAT Pointed Survey (WARPS)

C. A. Scharf·L. R. Jones·E. Perlman·H. Ebeling·G. Wegner·M. Malkan·D. Horner

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Abstract

A new flux limited catalogue of low luminosity (Lx <= 10^44 erg/s) X-ray galaxy clusters and groups covering a redshift range of z~0.1 to z~0.7 has been produced from the WARPS project. We present the number counts of this low luminosity population at high redshifts (z>0.3). The results are consistent with an unevolving population which does not exhibit the evolution seen in the higher luminosity cluster population. These observations can be qualitatively described by self-similarly evolving dark matter and preheated IGM models of X-ray cluster gas, with a power law index for the spectrum of matter density fluctuations n >= -1.

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C. A. Scharf, L. R. Jones, E. Perlman, H. Ebeling, G. Wegner, M. Malkan, D. Horner. 1997-01-31. Cluster Evolution in the Wide Angle ROSAT Pointed Survey (WARPS). https://arxiv.org/abs/astro-ph/9702009

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