Red Giants of Population II. IV
Abstract
The evolutionary phases of a Population II star through the helium flash have been recomputed with improved representations for several of the relevant physical processes. The new computations show that the helium flash is less extreme than indicated by the earlier, less accurate computations; the nuclearenergy release reaches only 1011 LQ at the peak, and the rate of evolutionary changes now appears to be too slow for major hydrodynamic effects. On the other hand, the new computations confirm the earlier results indicating that the convective core at its greatest extent (after the flash) misses the hydrogen-rich region by about two density scale heights. Accordingly, in view of the very small overshooting from convective cores found in a recent separate investigation, it now appears highly likely that the helium flash does not lead to mixing in the star.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1966
- DOI:
- Bibcode:
- 1966ApJ...145..496H