2008/02/26 by Yeong‐Shang Loh, Y. -S. Loh, E. Ellingson +7 · 39 citations
Environmental Science · Physics and Astronomy · #Astronomy #Astrophysics #Bimodality #Brightest cluster galaxy #Cluster (spacecraft) #Demography #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Physics #Population #Redshift #Remote Sensing in Agriculture #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/587830
published in The Astrophysical Journal 680(1), 214-223 (IOP Publishing) · 27 pages, 7 figures, accepted for publication in the ApJ
arxiv created 2008/02/26 · openalex publication_date 2008/06/06 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present the evolution of the color-magnitude distribution of galaxy clusters from z = 0.45 to z = 0.9 using a homogeneously selected sample of ~1000 clusters drawn from the Red-Sequence Cluster Survey (RCS). The red fraction of galaxies decreases as a function of increasing redshift for all clustercentric radii, consistent with the Butcher-Oemler effect, and suggesting that the cluster blue population may be identified with newly infalling galaxies. We also find that the red fraction at the core has a shallower evolution compared with that at the cluster outskirts. Detailed examination of the color distribution of blue galaxies suggests that they have colors consistent with normal spirals and may redden slightly with time. Galaxies of starburst spectral type contribute less than 5% of the increase in the blue population at high redshift, implying that the observed Butcher-Oemler effect is not caused by a unobscured starbursts, but is more consistent with a normal coeval field population.