Nucleosynthesis in Core-collapse Supernova Explosions Triggered by a Quark-Hadron Phase Transition

The Astrophysical Journal (Impact Factor: 5.99). 12/2011; 758(1). DOI: 10.1088/0004-637X/758/1/9
Source: arXiv


We explore heavy element nucleosynthesis in the explosion of massive stars
which are triggered by a quark-hadron phase transition during the early post
bounce phase of core-collapse supernovae. The present study is based on general
relativistic radiation hydrodynamics simulations with three-flavor Boltzmann
neutrino transport in spherical symmetry, which utilize a quark-hadron hybrid
equation of state based on the MIT bag model for strange quark matter. The
quark-hadron phase transition inside the stellar core forms a shock wave
propagating towards the surface of the proto-neutron star. The shock wave
results in an explosion and ejects neutron-rich matter which is piled up or
accreting on the proto-neutron star. Later, during the cooling phase, the
proto-neutron star develops a proton-rich neutrino-driven wind. We present a
detailed analysis of the nucleosynthesis outcome in both neutron-rich and
proton-rich ejecta and compare our integrated nucleosynthesis with observations
of metal poor stars.

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Available from: Nobuya Nishimura
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