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Carbon burning in intermediate mass primordial stars

P. Gil-Pons·T. Suda·M. Y. Fujimoto·E. Garcia-Berro
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Abstract

The evolution of a zero metallicity 9 M_s star is computed, analyzed and compared with that of a solar metallicity star of identical ZAMS mass. Our computations range from the main sequence until the formation of a massive oxygen-neon white dwarf. Special attention has been payed to carbon burning in conditions of partial degeneracy as well as to the subsequent thermally pulsing Super-AGB phase. The latter develops in a fashion very similar to that of a solar metallicity 9 M_s star, as a consequence of the significant enrichment in metals of the stellar envelope that ensues due to the so-called third dredge-up episode. The abundances in mass of the main isotopes in the final ONe core resulting from the evolution are X(^{16}O) approx 0.59, X(^{20}Ne) approx 0.28 and X(^{24}Mg) approx 0.05. This core is surrounded by a 0.05 M_s buffer mainly composed of carbon and oxygen, and on top of it a He envelope of mass 10^{-4} M_s

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P. Gil-Pons, T. Suda, M. Y. Fujimoto, E. Garcia-Berro. 2004-12-17. Carbon burning in intermediate mass primordial stars. https://doi.org/10.1051/0004-6361%3A20041755

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