This process is experimental and the keywords may be updated as the learning algorithm improves.īecker, S., and Iben, I. These keywords were added by machine and not by the authors. The early R stars may result from mixing at the helium core flash.

The results of calculations of helium core flashes in stars at the tip of the first giant branch are also discussed. The Ba and CH stars, which may all have white dwarf companions, are probably the result of mass transfer from N stars in binary systems. The quantitative agreement between the theory of shell flashes and observations is still not good. These results when compared with observations of cool giants with peculiar abundances in the Magellanic Clouds unambiguously show that there is an evolutionary sequence up the AGB in the sense M→S→C (N and late R) which is caused by dredge-up of carbon and s-process elements at helium shell flashes. The results of calculations of helium shell flashes in stars on the asympototic giant branch (AGB) are discussed.

Dredge up