JHKs photometry of Sculptor dSph galaxy

With the aid of published kinematic data definite galaxy members are identified and the width in J-K of the colour-magnitude diagram is shown to be consistent with an old population of stars with a large range in metal abundance. We identify two Asymptotic Giant Branch variables, both carbon Miras, with periods of 189 and 554d, respectively, and discuss their ages, metallicities and mass-loss as well as their positions in the Mira period-luminosity diagram.

There is evidence for a general period-age relation for Local Group Miras. The mass-loss rate for the 554d variable, MAG29, appears to be consistent with that found for Miras of comparable period in other Local Group galaxies.