Christian Winteler, Roger Kaeppeli, Albino Perego, Almudena Arcones, Nicolas Vasset, Nobuya Nishimura, Matthias Liebendoerfer, Friedrich-Karl Thielemann
We examine magneto-rotationally driven supernovae as sources of r-process elements in the early Galaxy. On the basis of thermodynamic histories of tracer particles from a 3D magnetohydrodynamical core-collapse supernova model with approximated neutrino transport, we perform nucleosynthesis calculations with and without considering the effects of neutrino absorption reactions on the electron fraction ($Y_{e}$) during post-processing. We find that the peak distribution of $Y_{e}$ in the ejecta is shifted from $\sim0.15$ to $\sim0.17$ and broadened towards higher $Y_{e}$ due to neutrino absorption. Nevertheless, in both cases the second and third peak of the solar r-process element distribution can be well reproduced. The rare progenitor configuration that was used here, characterized by a high rotation rate and a large magnetic field necessary for the formation of bipolar jets, could naturally provide a site for the strong r-process in agreement with observations of the early galactic chemical evolution.
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http://arxiv.org/abs/1203.0616
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