Distant galaxy clusters in the XMM Large Scale Structure survey

作者：Willis J P^*; Clerc N; Bremer M N; Pierre M; Adami C; Ilbert O; Maughan B; Maurogordato S; Pacaud F; Valtchanov I; Chiappetti L; Thanjavur K; Gwyn S; Stanway E R; Winkworth C

来源：Monthly Notices of the Royal Astronomical Society, 2013, 430(1): 134-156.

DOI：10.1093/mnras/sts540

• galaxies: clusters: general
• galaxies: high-redshift

Distant galaxy clusters provide important tests of the growth of large-scale structure in addition to highlighting the process of galaxy evolution in a consistently defined environment at large look-back time. We present a sample of 22 distant (z %26gt; 0.8) galaxy clusters and cluster candidates selected from the 9 deg(2) footprint of the overlapping X-ray Multi Mirror (XMM) Large Scale Structure (LSS), CFHTLS-Wide and Spitzer-SWIRE surveys. Clusters are selected as extended X-ray sources with an accompanying overdensity of galaxies displaying optical to mid-infrared photometry consistent with z %26gt; 0.8. Nine clusters have confirmed spectroscopic redshifts in the interval 0.8 %26lt; z %26lt; 1.2, four of which are presented here for the first time. A further 11 candidate clusters have between 8 and 10 band photometric redshifts in the interval 0.8 %26lt; z %26lt; 2.2, while the remaining two candidates do not have information in sufficient wavebands to generate a reliable photometric redshift. All of the candidate clusters reported in this paper are presented for the first time. Those confirmed and candidate clusters with available near-infrared photometry display evidence for a red sequence galaxy population, determined either individually or via a stacking analysis, whose colour is consistent with the expectation of an old, coeval stellar population observed at the cluster redshift. We further note that the sample displays a large range of red fraction values indicating that the clusters may be at different stages of red sequence assembly. We compare the observed X-ray emission to the flux expected from a suite of model clusters and find that the sample displays an effective mass limit M-200 similar to 1 x 10(14) M-circle dot with all clusters displaying masses consistent with M-200 %26lt; 5 x 10(14) M-circle dot. This XMM distant cluster study represents a complete sample of X-ray-selected z %26gt; 0.8 clusters. We discuss the importance of this sample to investigate the abundance of high-redshift clusters and to provide a relatively unbiased view of distant cluster galaxy populations.

• 出版日期2013-3
• 单位中国地震局