Bibcode
DOI
Gallart, Carme
Bibliographical reference
Astrophysical Journal Letters v.495, p.L43
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3
1998
Citations
67
Refereed citations
57
Description
The huge photometric databases that are being created for stars in the
Magellanic Clouds and in Local Group galaxies not only allow a detailed
study of the star formation history of these systems but also provide
important information on stellar evolutionary theory. Two low-level
features above the red clump in the LMC color-magnitude diagram (CMD)
have been discussed by Zaritsky & Lin and Alcock et al. as the
possible signature of an intervening population. I conclude that one of
the features, which has also been associated with the red giant branch
(RGB) bump predicted by theory and observed in globular clusters, is
instead produced during asymptotic giant branch (AGB) evolution. I will
call it the AGB bump. In this Letter, it will be shown that the stellar
evolution predictions about the position and strength of the AGB bump
are in very good agreement with the observed structures in the LMC, M31,
and globular clusters. The position in the CMD of the other feature is
consistent with the location of the blue loops of stars that are a few
hundred megayears old, and it has also been observed in the CMD of other
galaxies with a young stellar population.