Thermohaline mixing in low-mass giants

Thermohaline mixing has recently been proposed to occur in low mass red giants, with large consequences for the chemical yields of low mass stars. We investigate the role of thermohaline mixing during the evolution of stars between 1M⊙ and 3M⊙, in comparison to other mixing processes acting in these stars. We confirm that thermohaline mixing has the potential to destroy most of the He which is produced earlier on the main sequence during the red giant stage. In our models we find that this process is working only in stars with initial mass M ∼ < 1.5M⊙. Moreover, we report that thermohaline mixing can be present during core helium burning and beyond in stars which still have a He reservoir. While rotational and magnetic mixing is negligible compared to the thermohaline mixing in the relevant layers, the interaction of thermohaline motions with differential rotation and magnetic fields may be essential to establish the time scale of thermohaline mixing in red giants.