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 Academic Article uri icon

abstract

  • © 2016. The American Astronomical Society. All rights reserved. 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.

author list (cited authors)

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

publication date

  • January 1, 2011 11:11 AM