A census of AGB stars in Local Group galaxies: II. NGC 185 and NGC 147

We present results of our ongoing photometric survey of Local Group galaxies, using a four filter technique based on the method of Wing (1971) to identify and characterise the late-type stellar content. Two narrow band filters centred on spectral features of TiO and CN allow us to distinguish between AGB stars of different chemistries (M-type (O-rich) and C-type (C-rich)). The major parts of two dwarf galaxies of the M 31 subgroup - NGC 185 and NGC 147 - were observed. From photometry in V and i we estimate the tip of the RGB, and derive distance moduli respectively. With additional photometric data in the narrow band filters TiO and CN we identify 154 new AGB carbon stars in NGC 185 and 146 in NGC 147. C/M ratios are derived, as well as mean absolute magnitudesMi� , bolometric magnitudes Mbol, luminosity functions, and the spatial/radial distributions of the C stars in both galaxies.

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