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arXiv · 1004.4683

The X-ray brightest clusters of galaxies from the Massive Cluster Survey

H. Ebeling·A. C. Edge·A. Mantz·E. Barrett·J. P. Henry·C. J. Ma·L. van Speybroeck
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Abstract

We present a statistically complete sample of very X-ray luminous galaxy clusters detected in the MAssive Cluster Survey (MACS). This second MACS release comprises all 34 MACS clusters with nominal X-ray fluxes in excess of 2x10^(-12) erg/s/cm^2 (0.1-2.4 keV) in the ROSAT Bright Source Catalogue; two thirds of them are new discoveries. Extending over the redshift range from 0.3 to 0.5, this subset complements the complete sample of the 12 most distant MACS clusters (z>0.5) published in 2007 and further exemplifies the efficacy of X-ray selection for the compilation of samples of intrinsically massive galaxy clusters. Extensive follow-up observations with Chandra/ACIS led to three additional MACS cluster candidates being eliminated as (predominantly) X-ray point sources. For another four clusters --- which, however, remain in our sample of 34 --- the point-source contamination was found to be about 50%. The median X-ray luminosity of 1.3x10^45 erg/s (0.1-2.4 keV, Chandra, within r_500) of the clusters in this subsample demonstrates the power of the MACS survey strategy to find the most extreme and rarest clusters out to significant redshift. A comparison of the optical and X-ray data for all clusters in this release finds a wide range of morphologies with no obvious bias in favour of either relaxed or merging systems.

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H. Ebeling, A. C. Edge, A. Mantz, E. Barrett, J. P. Henry, C. J. Ma, L. van Speybroeck. 2010-04-27. The X-ray brightest clusters of galaxies from the Massive Cluster Survey. https://doi.org/10.1111/j.1365-2966.2010.16920.x

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