Adiabatic Mass Loss and the Outcome of the Common Envelope Phase of Binary Evolution
Abstract
We have developed a new method for calculating common envelope (CE) events based on explicit consideration of the donor star's structural response to adiabatic mass loss. In contrast to existing CE prescriptions, which specify a priori the donor's remnant mass, we determine this quantity self-consistently and find that it depends on binary and CE parameters. This aspect of our model is particularly important to realistic modeling for upper main-sequence star donors without strongly degenerate cores (and hence without a clear core/envelope boundary). We illustrate the central features of our method by considering CE events involving 10 M sun donors on or before their red giant branch. For such donors, the remnant core mass can be as much as 30% larger than the star's He-core mass. Applied across a population of such binaries, our methodology results in a significantly broader remnant mass and final orbital separation distribution and a 20% increase in CE survival rates as compared to previous prescriptions for the CE phase.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 2010
- DOI:
- 10.1088/2041-8205/719/1/L28
- arXiv:
- arXiv:1007.1036
- Bibcode:
- 2010ApJ...719L..28D
- Keywords:
-
- binaries: close;
- stars: evolution;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 4 pages, 3 figures