GALAXIES IN X-RAY SELECTED CLUSTERS AND GROUPS IN DARK ENERGY SURVEY DATA. I. STELLAR MASS GROWTH OF BRIGHT CENTRAL GALAXIES SINCE <i>z</i> 1.2

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, ight)}^{0.24pm 0.08}{(1+z)}^{-0.19pm 0.34}$?> m * ∝ M 200 1.5 × 10 14 M ⊙ 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 M 200,z =1013.8 M ; at z = 1.0: m *,BCG appears to have grown by 0.130.11 dex, in tension at the 2.5 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.

Zhang, Y., Miller, C., McKay, T., Rooney, P., Evrard, A. E., Romer, A. K., ... da Costa, L. N.

Zhang, Y||Miller, C||McKay, T||Rooney, P||Evrard, AE||Romer, AK||Perfecto, R||Song, J||Desai, S||Mohr, J||Wilcox, H||Bermeo-Hernandez, A||Jeltema, T||Hollowood, D||Bacon, D||Capozzi, D||Collins, C||Das, R||Gerdes, D||Hennig, C||Hilton, M||Hoyle, B||Kay, S||Liddle, A||Mann, RG||Mehrtens, N||Nichol, RC||Papovich, C||Sahlen, M||Soares-Santos, M||Stott, J||Viana, PT||Abbott, T||Abdalla, FB||Banerji, M||Bauer, AH||Benoit-Levy, A||Bertin, E||Brooks, D||Buckley-Geer, E||Burke, DL||Rosell, A Carnero||Castander, FJ||Diehl, HT||Doel, P||Cunha, CE||Eifler, TF||Fausti Neto, A||Fernandez, E||Flaugher, B||Fosalba, P||Frieman, J||Gaztanaga, E||Gruen, D||Gruendl, RA||Honscheid, K||James, D||Kuehn, K||Kuropatkin, N||Lahav, O||Maia, MAG||Makler, M||Marshall, JL||Martini, Paul||Miquel, R||Ogando, R||Plazas, AA||Roodman, A||Rykoff, ES||Sako, M||Sanchez, E||Scarpine, V||Schubnell, M||Sevilla, I||Smith, RC||Sobreira, F||Suchyta, E||Swanson, MEC||Tarle, G||Thaler, J||Tucker, D||Vikram, V||da Costa, LN

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