The Stellar Populations of dE galaxies in nearby Groups
Abstract
In this contribution initial results from colour-magnitude diagrams for five dEs in the M81 group are presented. The colour-magnitude diagrams, derived from HST/ACS images, reach well below the red giant branch tip and allow evaluation of distances and mean metallicities. Further, the intermediate-age upper-AGB stars seen in the diagrams allow estimates of the epochs of the last significant episode of star formation in the dEs. These epochs, and the relative numbers of upper-AGB to red giant branch stars, vary significantly from dE to dE. Preliminary inferences from similar HST/ACS data for five early-type dwarfs in the Sculptor group are also discussed.
Cite
@article{arxiv.astro-ph/0701051,
title = {The Stellar Populations of dE galaxies in nearby Groups},
author = {G. S. Da Costa},
journal= {arXiv preprint arXiv:astro-ph/0701051},
year = {2007}
}
Comments
6 pages, 3 figs, to appear in "From Stars to Galaxies", eds Vallenari, Tantalo, Portinari & Morretti, ASP Conf. Series