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

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 نشر من قبل Caleb Scharf
 تاريخ النشر 1997
  مجال البحث فيزياء
والبحث باللغة English
 تأليف C. A. Scharf




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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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