2008/06/30 by R. Gobat, P. Rosati, V. Strazzullo +3 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Cluster (spacecraft) #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Star cluster #Star formation #Stellar mass #Stellar population #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:200809531
10 pages, 11 figures, accepted for publication in A&A, references added, minor corrections
arxiv created 2008/07/15 · openalex publication_date 2008/07/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We derive the star formation histories of early-type galaxies at in both low and high density environments. To this purpose, we compare the co-added spectroscopic and 8–9 band photometric data of 43 mass selected early-type galaxies in the massive cluster RDCS J1252.9-2927 and the GOODS/CDF-S field with a large grid of composite stellar population models based on the Bruzual & Charlot templates. We find that the cluster early-type galaxies formed the bulk of their stars approximately 0.5 Gyr earlier than early-types in the field, whereas field early-types presumably finish forming their stellar content on a longer time scale. Such a difference is particularly evident at masses , whereas it becomes negligible for the most massive galaxies. While our differential analysis of the stellar population parameters of cluster and field galaxies in the same mass range convincingly shows distinct star formation histories, the absolute age difference remains model dependent. Using the star formation histories that best fit the SEDs of the red sequence galaxies in RDCS 1252.9-2927, we reconstruct the evolution of the cluster red sequence and find that it was established over 1 Gyr and is expected to dissolve by .