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A serendipitous survey for galaxy clusters by the XMM-Newton Survey Science Center

A. D. Schwope·G. Lamer·D. Burke·M. Elvis·M. G. Watson·M. P. Schulze·G. Szokoly·T. Urrutia
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Abstract

We describe the initial results of a programme to detect and identify extended X-ray sources found serendipitously in XMM-Newton observations. We have analysed 186 EPIC-PN images at high galactic latitude with a limiting flux of $1\times 10^{-14}$ \ergcms and found 62 cluster candidates. Thanks to the enhanced sensitivity of the XMM-Newton telescopes, the new clusters found in this pilot study are on the average fainter, more compact, and more distant than those found in previous X-ray surveys. At our survey limit the surface density of clusters is about 5 deg$^{-2}$. We also present the first results of an optical follow-up programme aiming at the redshift measurement of a large sample of clusters. The results of this pilot study give a first glimpse on the potential of serendipitous cluster science with XMM-Newton based on real data. The largest, yet to be fulfilled promise is the identification of a large number of high-redshift clusters for cosmological studies up to $z=1$ or 1.5.

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A. D. Schwope, G. Lamer, D. Burke, M. Elvis, M. G. Watson, M. P. Schulze, G. Szokoly, T. Urrutia. 2003-06-05. A serendipitous survey for galaxy clusters by the XMM-Newton Survey Science Center. https://doi.org/10.1016/j.asr.2003.04.073

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