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

Zhang, Y. and Miller, C. and McKay, T. and Rooney, P. and Evrard, A. E. and Romer, A. K. and Perfecto, R. and Song, J. and Desai, S. and Mohr, J. and Wilcox, H. and Bermeo-Hernandez, A. and Jeltema, T. and Hollowood, D. and Bacon, D. and Capozzi, D. and Collins, C. and Das, R. and Gerdes, D. and Hennig, C. and Hilton, M. and Hoyle, B. and Kay, S. and Liddle, A. and Mann, R. G. and Mehrtens, N. and Nichol, R. C. and Papovich, C. and Sahlen, M. and Soares-Santos, M. and Stott, J. and Viana, P. T. and Abbott, T. and Abdalla, F. B. and Banerji, M. and Bauer, A. H. and Benoit-Levy, A. and Bertin, E. and Brooks, D. and Buckley-Geer, E. and Burke, D. L. and Rosell, A. Carnero and Castander, F. J. and Diehl, H. T. and Doel, P. and Cunha, C. E. and Eifler, T. F. and Fausti Neto, A. and Fernandez, E. and Flaugher, B. and Fosalba, P. and Frieman, J. and Gaztanaga, E. and Gruen, D. and Gruendl, R. A. and Honscheid, K. and James, D. and Kuehn, K. and Kuropatkin, N. and Lahav, O. and Maia, M. A. G. and Makler, M. and Marshall, J. L. and Martini, Paul and Miquel, R. and Ogando, R. and Plazas, A. A. and Roodman, A. and Rykoff, E. S. and Sako, M. and Sanchez, E. and Scarpine, V. and Schubnell, M. and Sevilla, I. and Smith, R. C. and Sobreira, F. and Suchyta, E. and Swanson, M. E. C. and Tarle, G. and Thaler, J. and Tucker, D. and Vikram, V. and da Costa, L. N. (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. The Astrophysical Journal, 816 (2). ISSN 0004-637X

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, , 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 Mo; at z = 1.0: m∗,BCG appears to have grown by 0.13 ±0.11 dex, in tension at the ∼2.5σ 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.