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arXiv · 1203.0616

Magnetorotationally driven Supernovae as the origin of early galaxy $r$-process elements?

Christian Winteler·Roger Kaeppeli·Albino Perego·Almudena Arcones·Nicolas Vasset·Nobuya Nishimura·Matthias Liebendoerfer·Friedrich-Karl Thielemann
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Abstract

We examine magnetorotationally driven supernovae as sources of $r$-process elements in the early Galaxy. On the basis of thermodynamic histories of tracer particles from a three-dimensional 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 toward higher $Y_{e}$ due to neutrino absorption. Nevertheless, in both cases the second and third peaks 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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Christian Winteler, Roger Kaeppeli, Albino Perego, Almudena Arcones, Nicolas Vasset, Nobuya Nishimura, Matthias Liebendoerfer, Friedrich-Karl Thielemann. 2012-04-14. Magnetorotationally driven Supernovae as the origin of early galaxy $r$-process elements?. https://doi.org/10.1088/2041-8205%2F750%2F1%2Fl22

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