Formation of sdB-stars via common envelope ejection by substellar companions

  title={Formation of sdB-stars via common envelope ejection by substellar companions},
  author={M. Kramer and Fabian R. N. Schneider and Sebastian T. Ohlmann and Stephan Geier and Veronika Schaffenroth and R{\"u}ediger Pakmor and Friedrich K. Roepke},
  journal={arXiv: Solar and Stellar Astrophysics},
Common envelope (CE) phases in binary systems where the primary star reaches the tip of the red giant branch are discussed as a formation scenario for hot subluminous B-type (sdB) stars. For some of these objects, observations point to very low-mass companions. In hydrodynamical CE simulations with the moving-mesh code AREPO, we test whether low-mass objects can successfully unbind the envelope. The success of envelope removal in our simulations critically depends on whether or not the… 

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