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The XMM Large-Scale Structure Survey: An initial sample of galaxy groups and clusters to a redshift z<0.6

J. P. Willis·F. Pacaud·I. Valtchanov·M. Pierre·T. Ponman·A. Read·S. Andreon·B. Altieri·H. Quintana·S. Dos Santos·M. Birkinshaw·M. Bremer·P. A. Duc·G. Galaz·E. Gosset·L. Jones·J. Surdej
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Abstract

We present X-ray and optical spectroscopic observations of twelve galaxy groups and clusters identified within the XMM Large-Scale Structure (LSS) survey. Groups and clusters are selected as extended X-ray sources from a 3.5 deg2 XMM image mosaic above a flux limit 8e-15 ergs/s/cm2 in the [0.5-2] keV energy band. Deep BVRI images and multi-object spectroscopy confirm each source as a galaxy concentration located within the redshift interval 0.29<z<0.56. We combine line-of-sight velocity dispersions with the X-ray properties of each structure computed from a two-dimensional surface brightness model and a single temperature fit to the XMM spectral data. The resulting distribution of X-ray luminosity, temperature and velocity dispersion indicate that the XMM-LSS survey is detecting low-mass clusters and galaxy groups to redshifts z < 0.6. Confirmed systems display little or no evidence for X-ray luminosity evolution at a given X-ray temperature compared to lower redshift X-ray group and cluster samples. A more complete understanding of these trends will be possible with the compilation of a statistically complete sample of galaxy groups and clusters anticipated within the continuing XMM-LSS survey.

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J. P. Willis, F. Pacaud, I. Valtchanov, M. Pierre, T. Ponman, A. Read, S. Andreon, B. Altieri, H. Quintana, S. Dos Santos, M. Birkinshaw, M. Bremer, P. A. Duc, G. Galaz, E. Gosset, L. Jones, J. Surdej. 2005-07-29. The XMM Large-Scale Structure Survey: An initial sample of galaxy groups and clusters to a redshift z<0.6. https://doi.org/10.1111/j.1365-2966.2005.09651.x

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