Abstract

Contributed Talk - Splinter HotStars

Thursday, 15 September 2022, 16:35   (SFG 1030 / virtual HotStars)

A volume-complete sample of hot subluminous stars out to 500 pc using Gaia

H. Dawson, S. Geier, U. Heber, I. Pelisoli et al.
University of Potsdam

Hot subdwarf stars of spectral type O and B are found throughout the disk and halo of our Galaxy and whose observed properties place them on the Extreme Horizontal Branch of the Hertzsprung-Russel diagram. The consensus of their genesis is that they are likely formed as a consequence of extreme mass-loss during the red giant phase due to close binary interactions, though there are still many inconsistencies between theory and observation. Using Gaia's most recent data release (EDR3), I aim to provide a volume-limited sample of these stars out to 500 pc to enable direct comparison to evolutionary models in an unbiased way for the first time. In my talk, I will report on the current status of this sample, give preliminary space density and scale height estimates and hint on it's application in a variety of astrophysical fields.