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arXiv · astro-ph/0701051

The Stellar Populations of dE galaxies in nearby Groups

G. S. Da Costa
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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.

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G. S. Da Costa. 2007-01-02. The Stellar Populations of dE galaxies in nearby Groups. https://arxiv.org/abs/astro-ph/0701051

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