Extensive grids of TP-AGB models wereĬomputed using this scheme.
Moreover, the final possible shutĭown of the process is predicted. Inferring if and when dredge-up first occurs. Envelope integrations then allow determination of M_c^min as aįunction of stellar mass, metallicity, and pulse strength (see Wood 1981), thus Of the convective envelope, T_b^dred, at the stage of the post-flash luminosity In this approach, the usualĬriterion (based on a constant minimum core mass for the occurrence ofĭredge-up, M_c^min) is replaced by one on the minimum temperature at the base Pulsing asymptotic giant branch (TP-AGB) stars. Scheme for treating the third dredge-up in synthetic calculations of thermally Theoretical modelling is based on an improved Non-standard scenarios to explain the puzzling abundance pattern in NGC 1978.Download a PDF of the paper titled The third dredge-up and the carbon star luminosity functions in the Magellanic Clouds, by Paola Marigo (1 and 2) and 4 other authors Download PDF Abstract: We investigate the formation of carbon stars as a function of the stellar None of the theoretical schemes that we considered wasĪble to reproduce the observations appropriately. Ratios consistent with the occurrence of the third dredge-up. The C stars show carbon-to-oxygen and carbon isotopic These oxygen-rich stars do not seem to have undergone thirdĭredge-up episodes (yet). On the RGB coupled to a moderate oxygen enhancement in the chemicalĬomposition. In particular, we measure the surface abundance of ^C that can best be explained with moderate extra-mixing We seek to benchmark stellar evolutionary models of Picture of the stellar interior, particularly with regard to nucleosynthesisĪnd mixing mechanisms. To assess this contribution quantitatively, it is crucial to obtain a detailed Since theyĪre large in number, they contribute significantly to the cosmic matter cycle. In the final stages of their evolution by means of stellar winds. Lederer and 5 other authors Download PDF Abstract: Low-mass stars are element factories that efficiently release their products Download a PDF of the paper titled The puzzling dredge-up pattern in NGC 1978, by Michael T.
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