Speaker
Description
Canonical core-collapse supernova explosions driven by the neutrino-heating mechanism are presently ruled out as nucleosynthesis site for the production of heavy r-process elements with A ~ 195 (third r-process peak). Detailed numerical studies, with accurate neutrino transport and a sophisticated treatment of weak processes included, have shown that the ejected material yields neither sufficiently high entropies nor large neutron excess [1] for the production of elements with atomic numbers greater than 32 < Z < 50 [2], known as light neutron-capture elements. Here, a review of this caveat will be presented. Based on new insights, a possibility will be revisited that a few rare supernova explosion events can account for a strong r-process, i.e. the production of elements up to mass numbers of A ~ 195. Therefore, it has been shown recently that the appearance of exotic phases of hot and dense matter, associated with a 1st-order phase transition from ordinary nuclear matter to the quark-gluon plasma at the supernova interior, can trigger the onset of energetic supernova explosions of massive stars with zero-age main sequence masses of 40–50 solar masses [3]. Surprisingly, these events yield a strong r process, details of which will be presented and discussed in this talk.
References
[1] G. Mart??nez-Pinedo, T. Fischer, A. Lohs, and L. Huther, "Charged-Current Weak Interaction Processes in Hot and Dense Matter and its Impact on the Spectra of Neutrinos Emitted from Protoneutron Star Cooling," Phys. Rev. Lett. 109, 251104, 2012.
[2] G. Mart??nez-Pinedo, T. Fischer, and L. Huther, "Supernova neutrinos and nucleosynthesis," J. Phys. G Nuc. Phys. 41, 044008, 2014.
[3] T. Fischer, N.-U. F. Bastian, M.-R. Wu, S. Typel, T. Klahn, and D. B. Blaschke, "Quark deconfinement as a supernova explosion engine for massive blue supergiant star", Nat. Astron. 2, 980