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arXiv · 1408.6325

The XMM-LSS survey: the Class 1 cluster sample over the extended 11 deg$^2$ and its spatial distribution

N. Clerc·C. Adami·M. Lieu·B. Maughan·F. Pacaud·M. Pierre·T. Sadibekova·G. P. Smith·P. Valageas·B. Altieri·C. Benoist·S. Maurogordato·J. P. Willis
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Abstract

This paper presents 52 X-ray bright galaxy clusters selected within the 11 deg$^2$ XMM-LSS survey. 51 of them have spectroscopic redshifts ($0.05 3 σ$) constraints on the presence of a large void in the cluster distribution. We work out alternative hypotheses and demonstrate that a negative redshift evolution in the normalization of the $L_{X}-T_X$ relation (with respect to a self-similar evolution) is a plausible explanation for the observed deficit. We confirm this evolutionary trend by directly studying how C1 clusters populate the $L_{X}-T_X-z$ space, properly accounting for selection biases. We point out that a systematically evolving, unresolved, central component in clusters and groups (AGN contamination or cool core) can impact the classification as extended sources and be partly responsible for the observed redshift distribution.[abridged]

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N. Clerc, C. Adami, M. Lieu, B. Maughan, F. Pacaud, M. Pierre, T. Sadibekova, G. P. Smith, P. Valageas, B. Altieri, C. Benoist, S. Maurogordato, J. P. Willis. 2014-08-27. The XMM-LSS survey: the Class 1 cluster sample over the extended 11 deg$^2$ and its spatial distribution. https://doi.org/10.1093/mnras%2Fstu1625

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