Abstract
The evolution of a zero metallicity 9 Mstar 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 Mstar, 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) ≈ 0.59, X( 20 Ne) ≈ 0.28 and X( 24 Mg) ≈ 0.05. This core is surrounded by a 0.05 Mbuffer mainly composed of carbon and oxygen, and on top of it a He envelope of mass ∼10 −4 M� .
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