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تسجيل مستخدم جديدp-process in SNIA
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We explore SNIa as p-process sources in the framework of two-dimensional SNIa models using enhanced s-seed distributions as directly obtained from a sequence of thermal pulse instabilities. The SNIa WD precursor is assumed to have reached the Chandrasekhar mass limit in a binary system by mass accretion from a giant/main sequence companion. We apply the tracer-particle method to reconstruct the nucleosynthesis from the thermal histories of Lagrangian particles, passively advected in the hydrodynamic calculations. For each particle we follow the explosive nucleosynthesis with a detailed nuclear reaction network. We select tracers within the typical temperature range for p-process production, 1.5-3.7 109K, and analyse in detail their behaviour, exploring the influence of different s-process distributions on the p-process nucleosynthesis. We find that SNIa contribute to a large fraction of p-nuclei, both the light p-nuclei and the heavy-p nuclei at a quite flat average production factor. For the first time, the very abundant Ru and Mo p-isotopes are reproduced at the same level as the heavy p-nuclei. We investigate the metallicity effect on the p-process production. Starting with a range of s-seeds distributions obtained for different metallicities, running SNIa two-dimensional models and using a simple chemical evolution code, we give estimates of the SNIa contribution to the solar p-process composition. We find that SNIa contribute for at least 50% at the solar p-nuclei composition, in a primary way.
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