![]() Differential mass loss seems to be small thus justifying the use of an universal M i/M f relation for calculations of stellar and galactic evolution. More massive white dwarfs must have Ne/O cores after off-center carbon burning or are due to mergers or rotational lifting. The upper mass limit for C/O white dwarf production is smaller than hitherto assumed, around 6.5 M sun with white dwarf masses below 1 M sun. Comparison with theoretically predicted initial to final mass relations support the new evolutionary models with exponential diffusive overshoot which undergo core mass reduction by a strong third dredge-up. The Hyades white dwarfs must be relocated at higher initial masses since Hipparcos data lead to a reduced cluster age, and move also closer to the first TP relation. The higher the efciency l1 of the dredge-up episode, the greater the decrease in Mc, equal to l DMc. The effects of third dredge-up, the s -process, hot-bottom burning (CNO. as the second dredge up, and in some stars there may even be a third dredge up. The binaryc code currently uses the SSE/BSE package at its core to provide. Recent stellar evolution models predict core masses at the beginning of the thermally pulsing asymptotic giant branch which practically coincide with final white dwarf masses derived for NGC 3532 and the binary white dwarf PG 0922+162. The mass of the core, Mc, is instantaneously reduced at each mixing episode 2. The core of a red-giant-branch star of up to a few solar masses stops. The initial-to final mass relation is revised in view of new theoretical and observational data. Finally, during 'dredge-up' phase, inward advance of the conĀ vective envelope eventually penetrates the erstwhile ISCZ and mixes freshly produced 12 C to the surface. ![]()
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