Testing the role of SNe Ia for galactic chemical evolution of p-nuclei with two-dimensional models and with s-process seeds at different metallicities
Röpke, Friedrich K.
The bulk of p isotopes is created in the "gamma processes" mainly by sequences of photodisintegrations and beta decays in explosive conditions in Type Ia supernovae (SNIa) or in core collapse supernovae (ccSN). The contribution of different stellar sources to the observed distribution of p-nuclei in the solar system is still under debate. We explore single degenerate Type Ia supernovae in the framework of two-dimensional SNIa delayed-detonation explosion models. Travaglio et al. discussed the sensitivity of p-nuclei production to different SNIa models, i.e., delayed detonations of different strength, deflagrations, and the dependence on selected s-process seed distributions. Here we present a detailed study of p-process nucleosynthesis occurring in SNIa with s-process seeds at different metallicities. Based on the delayed-detonation model DDT-a of TRV11, we analyze the dependence of p-nucleosynthesis on the s-seed distribution obtained from different strengths of the 13C pocket. We also demonstrate that 208Pb seed alone changes the p-nuclei production considerably. The heavy-s seeds (140 ≤A < 208) contribute with about 30%-40% to the total light-p nuclei production up to 132Ba (with the exception of 94Mo and 130Ba, to which the heavy-s seeds contribute with about 15% only). Using a Galactic chemical evolution code from Travaglio et al., we study the contribution of SNIa to the solar stable p-nuclei. We find that explosions of Chandrasekhar-mass single degenerate systems produce a large amount of p-nuclei in our Galaxy, both in the range of light (A ≤ 120) and heavy p-nuclei, at almost flat average production factors (within a factor of about three). We discussed in details p-isotopes such as 94Mo with a behavior diverging from the average, which we attribute to uncertainties in the nuclear data or in SNIa modeling. Li et al. find that about 70% of all SNeIa are normal events. If these are explained in the framework of explosions of Chandrasekhar-mass white dwarfs resulting from the single-degenerate progenitor channel, we find that they are responsible for at least 50% of the p-nuclei abundances in the solar system.