2006/05/24 by Zhongmu Li, Fenghui Zhang, Zhanwen Han
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Brightest cluster galaxy #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy group #Lenticular galaxy #Peculiar galaxy #Physics #Scientific Research and Discoveries #Star formation #Stellar population #Surface brightness fluctuation #astro-ph
paper · pdf · doi:10.1088/1009-9271/6/6/05
published as Chin.J.Astron.Astrophys.6:669-679,2006 · 15 pages, 10 figures, accepted for publication to ChJAA
arxiv created 2006/05/24 · openalex publication_date 2006/10/01 · arxiv updated 2014/10/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We determined the relative stellar ages and metallicities of about 80 elliptical galaxies in both low and high density environments using the latest binary stellar population (BSP) synthesis model and tested the predictions of a recent hierarchical formation model that adopted the new ΛCDM cosmology. The stellar ages and metallicities were estimated from two high-quality published spectra line indices, the Hβ and [MgFe] indices. The results show that the stellar populations of elliptical galaxies are older than 3.9 Gyr and more metal rich than 0.02. Most of our results are in agreement with the model predictions: (1) elliptical galaxies in denser environment are redder and have older populations than field galaxies; (2) elliptical galaxies with more massive stellar components are redder and have older and more metal rich populations than less massive ones; (3) the most massive galaxies have the oldest and most metal rich stars. However, some of our results differ from the model predictions on the metallicity distributions of low- and high-density elliptical galaxies and the dependence on the distance to the cluster center.