The Galactic Population of Post-Asymptotic Giant Branch Stars: First Distance Catalogue

Abstract

We have commenced a detailed analysis of the known sample of Galactic post-AGB stars compiled in the Torun catalogue of Szczerba et al. We present homogeneously derived distances for the 209 likely and 87 possible catalogued post-AGB stars from that compilation. Knowing distances are essential in determining meaningful physical characteristics for these sources and this has been difficult to determine for most objects previously. The distances were determined by modelling their spectral energy distributions (SEDs) with multiple black-body curves, and integrating under the overall fit to determine the total distance-dependent flux. Combining this flux with an assumed luminosity then leads to a distance. For the Galactic thin disk objects, we use three luminosity bins based on typical observational characteristics, ranging between 3500 and 10000 L_sun. We further adopt a default luminosity of 2000 L_sun for old Population II objects. We have also applied the above technique to a large sample of nebulae not in the current edition of the Torun catalogue.