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arXiv · 0708.3671

A Multiwavelength Analysis of the Strong Lensing Cluster RCS 022434-0002.5 at z=0.778

Amalia K. Hicks·Erica Ellingson·Henk Hoekstra·Mike Gladders·Howard Yee·Mark Bautz·David Gilbank·Tracy Webb·Rob Ivison
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Abstract

We present the results of two (101 ks total) Chandra observations of the z=0.778 optically selected lensing cluster RCS022434-0002.5, along with weak lensing and dynamical analyses of this object. An X-ray spectrum extracted within R(2500) (362 h(70)^(-1) kpc) results in an integrated cluster temperature of 5.1 (+0.9,-0.5) keV. The surface brightness profile of RCS022434-0002.5 indicates the presence of a slight excess of emission in the core. A hardness ratio image of this object reveals that this central emission is primarily produced by soft X-rays. Further investigation yields a cluster cooling time of 3.3 times 10^9 years, which is less than half of the age of the universe at this redshift given the current LCDM cosmology. A weak lensing analysis is performed using HST images, and our weak lensing mass estimate is found to be in good agreement with the X-ray determined mass of the cluster. Spectroscopic analysis reveals that RCS022434-0002.5 has a velocity dispersion of 900 +/- 180 km/s, consistent with its X-ray temperature. The core gas mass fraction of RCS022434-0002.5 is, however, found to be three times lower than expected universal values. The radial distribution of X-ray point sources within R(200) of this cluster peaks at ~0.7 R(200), possibly indicating that the cluster potential is influencing AGN activity at that radius. Correlations between X-ray and radio (VLA) point source positions are also examined.

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Amalia K. Hicks, Erica Ellingson, Henk Hoekstra, Mike Gladders, Howard Yee, Mark Bautz, David Gilbank, Tracy Webb, Rob Ivison. 2007-08-27. A Multiwavelength Analysis of the Strong Lensing Cluster RCS 022434-0002.5 at z=0.778. https://doi.org/10.1086/522879

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