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Carbon Star Survey of Local Group Dwarf Galaxies. II. Pegasus, DDO 210 and Tucana

P. Battinelli·S. Demers
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Abstract

We present the latest results of our ongoing four filter photometric survey of C stars in Local Group dwarf irregular galaxies. Observations of the two low luminosity dwarf irregular galaxies, Pegasus and DDO 210, revealed respectively 40 and 3 C stars, assuming that the reddening of Pegasus is negligible. No C stars were identified in Tucana. Our observations permit the estimation of the CMD contamination by foreground M dwarf thus yielding reliable C/M ratios. Our R, I photometry of the C stars cannot be used to solve the extinction controversy toward Pegasus. The three C stars in DDO 210 are quite bright when compared to C star populations in dwarf galaxies. A larger fainter population in that galaxy seems however improbable. The statistics of C stars, currently on hand for dwarf galaxies, show a well-defined trend with the absolute magnitude of galaxies.

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P. Battinelli, S. Demers. 2000-08-03. Carbon Star Survey of Local Group Dwarf Galaxies. II. Pegasus, DDO 210 and Tucana. https://doi.org/10.1086/301546

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