We characterize the properties and evolution of bright central galaxies (BCGs) and the surrounding intracluster light (ICL) in galaxy clusters identified in the Dark Energy Survey and Atacama Cosmology Telescope Survey (DESACT) overlapping regions, covering the redshift range 0.20 < z < 0.80. Over this redshift range, we measure no change in the ICL’s stellar content (between 50 and 300 kpc) in clusters with log10(M200m,SZ/M⊙) >14.4. We also measure the stellar mass–halo mass (SMHM) relation for the BCG+ICL system and find that the slope, β, which characterizes the dependence of M200m,SZ on the BCG+ICL stellar mass, increases with radius. The outskirts are more strongly correlated with the halo than the core, which supports that the BCG+ICL system follows a twophase growth, where recent growth (z < 2) occurs beyond the BCG’s core. Additionally, we compare our observed SMHM relation results to the IllustrisTNG3001 cosmological hydrodynamic simulations and find moderate qualitative agreement in the amount of diffuse light. However, the SMHM relation’s slope is steeper in TNG3001 and the intrinsic scatter is lower, likely from the absence of projection effects in TNG3001. Additionally, we find that the ICL exhibits a colour gradient such that the outskirts are bluer than the core. more »
 Authors:
 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
 Publication Date:
 NSFPAR ID:
 10400650
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Volume:
 521
 Issue:
 1
 Page Range or eLocationID:
 p. 478496
 ISSN:
 00358711
 Publisher:
 Oxford University Press
 Sponsoring Org:
 National Science Foundation
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