Distant clusters of galaxies in a deep XMM-Newton observation
Abstract
The XMM-Newton Distant Cluster Project (XDCP) aims at the identification of a well defined sample of X-ray selected clusters of galaxies at redshifts z ≥ 0.8. As part of this project, we analyse the deep archival XMM-Newton exposure of LBQS 2212-1759 to quantify the cluster content. We validate the optical follow-up strategy as well as the X-ray selection function. We base the cluster identification of the extended X-ray sources on deep imaging with the ESO-VLT and on the CFHT-LS. The confirmation of cluster candidates is done by VLT/FORS2 spectroscopy. Photometric redshifts from CFTH-LS D4 are utilised to confirm the effectiveness of the X-ray cluster selection method. The survey sensitivity is computed to have a flux limit of S_{0.5-2.0 keV}∼ 2.5×10-15 erg s-1 for 50 % completeness in an area ∼ 0.13 deg2. We detect six clusters of galaxies above this level both in X-rays and the optical. Two newly discovered X-ray luminous clusters of galaxies in this work are at z≥1.0 and one is at z=0.41. The constructed log N-log S tends to favour a scenario where no evolution in the cluster X-ray luminosity function takes place.
- Publication:
-
Astronomische Nachrichten
- Pub Date:
- April 2013
- DOI:
- 10.1002/asna.201211883
- Bibcode:
- 2013AN....334..470D
- Keywords:
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- cosmology: observations;
- cosmology: large-scale structure;
- dark matter;
- galaxies: clusters: general;
- surveys;
- X-rays: surveys