Contributed Talk - Splinter Stellar

Thursday, 24 September 2020, 16:59   (virtual room M)

The First Volume-Limited Complete Catalogue of Hot Subdwarf Stars

Harry Dawson, Ingrid Pelisoli, Stephan Geier, et al.
Institut für Physik und Astronomie, Universität Potsdam

Hot subdwarf stars of spectral type O and B are evolved, compact, subluminous, core He-burning stars that reside on the Extreme Horizontal Branch of the Hertzsprung-Russel diagram. They are likely formed as a consequence of mass-loss during the red giant phase, either at or before the helium flash via close binary interactions. They thus play a vital role in our understanding of binary evolution. To study their formation and evolution, the analysis of a statistically significant, complete, and volume-limited sample is required, which presently does not exist. Published catalogues tend to be incomplete, have limited coverage, are inhomogeneous, and possess complicated selection biases. With the advent of Gaia DR2, the ambition is now to compile the first complete, volume-limited sample of spectroscopically confirmed hot subdwarf stars within 500pc. In this talk, I will report on the current status of this sample.