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arXiv · astro-ph/0205397

The Brightest AGB Stars in the Leo I Dwarf Spheroidal Galaxy

Abstract

The first results of a study of the the dwarf spheroidal galaxy, Leo I, using the new Japanese-South African Infrared Survey Facility (IRSF) are presented. J,H,K_{s} observations show that most, if not all, of at least the top one magnitude of the AGB is populated by carbon stars. These objects form a tight sequence in the K_{s} - (J-K_{s}) plane. In addition there are five very red objects which are believed to be dust enshrouded AGB stars. They have Mbol near -5.0 and are at the AGB tip. Comparison with carbon Miras in Magellanic Cloud clusters and taking into account other evidence on the ages and metallicities of Leo I populations suggests that these obscured stars belong to the youngest significant population of Leo I and have ages of ~2 Gyr. Some of them can be shown to be variable.

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John Menzies, Michael Feast, Toshihiko Tanabe, Patricia Whitelock, Yoshikazu Nakada. 2002-05-23. The Brightest AGB Stars in the Leo I Dwarf Spheroidal Galaxy. https://doi.org/10.1046/j.1365-8711.2002.05759.x

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