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arXiv · 1503.07188

A Multi-Wavelength Mass Analysis of RCS2 J232727.6-020437, a ~3x10$^{15}$M$_{\odot}$ Galaxy Cluster at z=0.7

K. Sharon·M. D. Gladders·D. P. Marrone·H. Hoekstra·E. Rasia·H. Bourdin·D. Gifford·A. K. Hicks·C. Greer·T. Mroczkowski·L. F. Barrientos·M. Bayliss·J. E. Carlstrom·D. G. Gilbank·M. Gralla·J. Hlavacek-Larrondo·E. Leitch·P. Mazzotta·C. Miller·S. J. C. Muchovej·T. Schrabback·H. K. C. Yee
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Abstract

We present an initial study of the mass and evolutionary state of a massive and distant cluster, RCS2 J232727.6-020437. This cluster, at z=0.6986, is the richest cluster discovered in the RCS2 project. The mass measurements presented in this paper are derived from all possible mass proxies: X-ray measurements, weak-lensing shear, strong lensing, Sunyaev Zel'dovich effect decrement, the velocity distribution of cluster member galaxies, and galaxy richness. While each of these observables probe the mass of the cluster at a different radius, they all indicate that RCS2 J232727.6-020437 is among the most massive clusters at this redshift, with an estimated mass of M_200 ~3 x10^15 h^-1 Msun. In this paper, we demonstrate that the various observables are all reasonably consistent with each other to within their uncertainties. RCS2 J232727.6-020437 appears to be well relaxed -- with circular and concentric X-ray isophotes, with a cool core, and no indication of significant substructure in extensive galaxy velocity data.

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K. Sharon, M. D. Gladders, D. P. Marrone, H. Hoekstra, E. Rasia, H. Bourdin, D. Gifford, A. K. Hicks, C. Greer, T. Mroczkowski, L. F. Barrientos, M. Bayliss, J. E. Carlstrom, D. G. Gilbank, M. Gralla, J. Hlavacek-Larrondo, E. Leitch, P. Mazzotta, C. Miller, S. J. C. Muchovej, T. Schrabback, H. K. C. Yee. 2015-03-24. A Multi-Wavelength Mass Analysis of RCS2 J232727.6-020437, a ~3x10$^{15}$M$_{\odot}$ Galaxy Cluster at z=0.7. https://doi.org/10.1088/0004-637x/814/1/21

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