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Batch discovery of nine z~1 clusters using x-ray and K or R,z' images

S. Andreon·I. Valtchanov·L. R. Jones·B. Altieri·M. Bremer·J. Willis·M. Pierre·H. Quintana
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Abstract

We present results of an initial search for clusters of galaxies at z~1 and above, using data from 2.9 square degrees of XMM-Newton images. By selecting weak potentially extended X-ray sources with faint or no identifications in deep, ground-based optical imaging, we have constructed a starting sample of 19 high redshift cluster candidates. Near-IR and R,z' imaging of these fields identified nine of them as high redshift systems. Six of these were confirmed spectroscopically, three at z~1.0 and the other three in 0.8 ~1 clusters, after discarding "low" redshift systems at z <~ 0.92 is about 1.7 /deg2 (with 68 % confidence interval equal to [1.0,2.9]) for f_X >~2.5 10^{-15} ergs/cm2/s ([0.5-2] keV) and this is a lower limit, having screened not all potential z~1 candidate clusters. Coordinates, x-ray measures and evidence for nine x-ray selected high redshift clusters is given.

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S. Andreon, I. Valtchanov, L. R. Jones, B. Altieri, M. Bremer, J. Willis, M. Pierre, H. Quintana. 2005-03-10. Batch discovery of nine z~1 clusters using x-ray and K or R,z' images. https://doi.org/10.1111/j.1365-2966.2005.08998.x

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