Article

The XMM Cluster Survey: X-ray analysis methodology

E. J. Lloyd-DaviesAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHA. K. RomerAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHNicola MehrtensAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHMark HosmerAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHM. DavidsonSUPA Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJKivanc SabirliDepartment of Physics, Carnegie‐Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USARobert G. MannSUPA Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJMatt HiltonSchool of Mathematical Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South AfricaAndrew R. LiddleAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHP. T. P. VianaDepartamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169‐007 Porto, PortugalH. CampbellInstitute of Cosmology and Gravitation, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FXC. A. CollinsAstrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead Ch41 1LDE. N. DuboisAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHPeter E. FreemanDepartment of Statistics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USACraig HarrisonDepartment of Astronomy, University of Michigan, Ann Arbor MI 48109, USAB. HoyleScott T. KayJodrell Bank Centre for Astrophysics, School of Physics & Astronomy, The University of Manchester, Manchester M13 9PLE. S. KuwertzAstronomy Centre, University of Sussex, Falmer, Brighton BN1 9QHChristopher J. MillerDepartment of Astronomy, University of Michigan, Ann Arbor MI 48109, USAR. C. NicholM SahlénThe Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, SE-106 91 Stockholm, SwedenS. A. StanfordInstitute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory, Livermore CA 94551, USAJ. P. StottAstrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead Ch41 1LD

2011en

ABI

Abstract

The XMM Cluster Survey (XCS) is a serendipitous search for galaxy clusters using all publicly available data in the XMM-Newton Science Archive. Its main aims are to measure cosmological parameters and trace the evolution of X-ray scaling relations. In this paper we describe the data processing methodology applied to the 5776 XMM observations used to construct the current XCS source catalogue. A total of 3675 > 4s cluster candidates with >50 background-subtracted X-ray counts are extracted from a total non-overlapping area suitable for cluster searching of 410 deg2. Of these, 993 candidates are detected with >300 background-subtracted X-ray photon counts, and we demonstrate that robust temperature measurements can be obtained down to this count limit. We describe in detail the automated pipelines used to perform the spectral and surface brightness fitting for these candidates, as well as to estimate redshifts from the X-ray data alone. A total of 587 (122) X-ray temperatures to a typical accuracy of <40 (<10) per cent have been measured to date. We also present the methodology adopted for determining the selection function of the survey, and show that the extended source detection algorithm is robust to a range of cluster morphologies by inserting mock clusters derived from hydrodynamical simulations into real XMMimages. These tests show that the simple isothermal ß-profiles is sufficient to capture the essential details of the cluster population detected in the archival XMM observations. The redshift follow-up of the XCS cluster sample is presented in a companion paper, together with a first data release of 503 optically confirmed clusters.

Identifiers

DOI: 10.1111/j.1365-2966.2011.19117.x

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Cited by 20 references

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