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Variable stars as tracers of stellar populations in Local Group galaxies: Leo I and NGC 6822

L. Baldacci·F. Matonti·L. Rizzi·G. Clementini·E. V. Held·Y. Momany·L. Di Fabrizio·I. Saviane
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Abstract

Results are presented of a study of the variable star populations in the dwarf spheroidal galaxy Leo I and in the dwarf irregular galaxy NGC 6822, based on time series photometry obtained with the Wide Field Imager of the 2.2 m ESO/MPI telescope (Leo I) and the Very Large Telescope (NGC 6822). We found about 250 (lower limit) variables in Leo I most of which are RR Lyrae stars. In NGC 6822 we identified 450 candidate variables among which about 20 are RR Lyrae stars, and many are low-luminosity, small-amplitude Cepheids.

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L. Baldacci, F. Matonti, L. Rizzi, G. Clementini, E. V. Held, Y. Momany, L. Di Fabrizio, I. Saviane. 2003-05-27. Variable stars as tracers of stellar populations in Local Group galaxies: Leo I and NGC 6822. https://arxiv.org/abs/astro-ph/0305506

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