Abstract

Contributed Talk - Splinter Stellar

Friday, 25 September 2020, 10:32   (virtual room M)

A quantitative in-depth analysis of the prototype sdB+BD system SDSS J08205+0008

Veronika Schaffenroth, Sarah Casewell, David Schneider et al.
Universität Potsdam, University of Leicester, Universität Erlangen-Nürnberg

Subdwarf B stars are core-helium burning stars located on the extreme horizontal branch. Extensive mass loss on the red giant branch is necessary to form them, which is believed to originate from close binary evolution. It has been proposed that substellar companions could also lead to the required mass-loss when they are engulfed in the envelope of the red giant star. J08205+0008 was the first example of a hot subdwarf star with a close, substellar companion candidate to be found. Here we perform an in-depth re-analysis of this important system with much higher quality data allowing additional analysis methods. By combining all different methods we could put much tighter constraints on the mass and radius of the hot subdwarf and its companion confirming that the companion is most likely a massive brown dwarf.