Rooney, Philip, Romer, Kathy, Bermeo-Hernandez, Alberto and The DES Collaboration, et al (2016) Galaxies in X-ray selected clusters and groups in Dark Energy Survey Data. I. stellar mass growth of bright central galaxies since z~1.2. Astrophysical Journal, 816 (2). p. 98. ISSN 0004-637X

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Abstract

Using the science verification data of the Dark Energy Survey for a new sample of 106 X-ray selected clusters and groups, we study the stellar mass growth of bright central galaxies (BCGs) since redshift z ~ 1.2. Compared with the expectation in a semi-analytical model applied to the Millennium Simulation, the observed BCGs become under-massive/under-luminous with decreasing redshift. We incorporate the uncertainties associated with cluster mass, redshift, and BCG stellar mass measurements into an analysis of a redshift-dependent BCG-cluster mass relation, {m}*∝ ({M}200}/{1.5×{10}14{M}&sun;}) 0.24+/-0.08(1+z)-0.19+/- 0.34, and compare the observed relation to the model prediction. We estimate the average growth rate since z = 1.0 for BCGs hosted by clusters of M200,z = 1013.8 M&sun; at z = 1.0: m*,BCG appears to have grown by 0.13 ± 0.11 dex, in tension at the ˜2.5sigma significance level with the 0.40 dex growth rate expected from the semi-analytic model. We show that the build-up of extended intracluster light after z = 1.0 may alleviate this tension in BCG growth rates.

Item Type:	Article
Schools and Departments:	School of Mathematical and Physical Sciences > Physics and Astronomy
Subjects:	Q Science > QB Astronomy
Depositing User:	Richard Chambers
Date Deposited:	27 Jun 2016 10:41
Last Modified:	02 Jul 2019 20:23
URI:	http://sro.sussex.ac.uk/id/eprint/61732

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