English

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

Astrophysics 2009-11-13 v1

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.

Keywords

Cite

@article{arxiv.astro-ph/0508003,
  title  = {The XMM Large-Scale Structure Survey: An initial sample of galaxy groups and clusters to a redshift z<0.6},
  author = {J. P. Willis and F. Pacaud and I. Valtchanov and M. Pierre and T. Ponman and A. Read and S. Andreon and B. Altieri and H. Quintana and S. Dos Santos and M. Birkinshaw and M. Bremer and P. A. Duc and G. Galaz and E. Gosset and L. Jones and J. Surdej},
  journal= {arXiv preprint arXiv:astro-ph/0508003},
  year   = {2009}
}

Comments

18 pages, MNRAS accepted