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We provide a brief review of thermohaline physics and why it is a candidate extra mixing mechanism during the red giant branch (RGB). We discuss how thermohaline mixing (also called $delta$ $mu$ mixing) during the RGB due to helium-3 burning, is more complicated than the operation of thermohaline mixing in other stellar contexts (such as following accretion from a binary companion). We try to use observations of carbon depletion in globular clusters to help constrain the formalism and the diffusion coefficient or mixing velocity that should be used in stellar models. We are able to match the spread of carbon depletion for metal poor field giants but are unable to do so for cluster giants, which may show evidence of mixing prior to even the first dredge-up event.
Extremely metal-poor (EMP) stars are an integral piece in the puzzle that is the early Universe, and although anomolous subclasses of EMP stars such as carbon-enhanced metal-poor (CEMP) stars are well-studied, they make up less than half of all EMP s
Thermohaline mixing is a favoured mechanism for the so-called extra mixing on the red giant branch of low-mass stars. The mixing is triggered by the molecular weight inversion created above the hydrogen shell during first dredge-up when helium-3 burn
It is now widely accepted that globular cluster red giant branch stars owe their strange abundance patterns to a combination of pollution from progenitor stars and in situ extra mixing. In this hybrid theory a first generation of stars imprint abunda
We revise a magnetic buoyancy model that has recently been proposed as a mechanism for extra mixing in the radiative zones of low-mass red giants. The most important revision is our accounting of the heat exchange between rising magnetic flux rings a
We present post process neutron capture computations for Asymptotic Giant Branch stars of 1.5 to 3 Mo and metallicities -1.3 to 0.1. The reference stellar models are computed with the FRANEC code, using the Schwarzschilds criterion for convection. Mo