2002/05/23 by J. W. Menzies, John Menzies, M. W. Feast +7 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Asymptotic giant branch #Carbon star #Dwarf galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Large Magellanic Cloud #Physics #Stars #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2002.05759.x
published as Mon.Not.Roy.Astron.Soc. 335 (2002) 923 · 5 pages, 2 figures, accepted for publication in MNRAS
arxiv created 2002/05/23 · openalex publication_date 2002/10/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The first results of a study of the dwarf spheroidal galaxy Leo I using the new Nagoya–South African Infrared Survey Facility (IRSF) are presented. J, H and Ks observations show that most, if not all, of at least the top magnitude of the asymptotic giant branch (AGB) in Ks is populated by carbon stars. In addition there are five very red objects which are believed to be dust-enshrouded AGB stars. One of these is, remarkably, well outside the main body of the galaxy. Three of these obscured stars and five known carbon stars show variability in observations 11 months apart. One of the obscured stars has ΔKs= 0.87, making it highly likely that it, at least, is a Mira variable. The tip of the AGB is at Mbol∼−5.1, but further variability studies are necessary to obtain a definitive value. Comparison with carbon stars, both Miras and non-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.