Supernova neutrinos and explosive nucleosynthesis

Core-collapse supernovae eject huge amount of flux of energetic neutrinos. We studied the explosive nucleosynthesis in supernovae and found that several isotopes ⁷Li, ¹¹B, ⁹²Nb, ¹³⁸La and ¹⁸⁰Ta as well as r-process nuclei are affected by the neutrino interactions. The abundance of these isotopes therefore depends strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We discuss first how to determine the neutrino temperatures in order to explain the observed solar system abundances of these isotopes, combined with Galactic chemical evolution of the light nuclei and the heavy r-process elements. We then study the effects of neutrino oscillation on their abundances, and propose a novel method to determine the still unknown neutrino oscillation parameters, mass hierarchy and θ₁₃, simultaneously. There is recent evidence that SiC X grains from the Murchison meteorite may contain supernova-produced light elements ¹¹B and ⁷Li encapsulated in the presolar grains. Combining the recent experimental constraints on θ₁₃, we show that our method suggests at a marginal preference for an inverted neutrino mass hierarchy. Finally, we discuss supernova relic neutrinos that may indicate the softness of the equation of state (EoS) of nuclear matter as well as adiabatic conditions of the neutrino oscillation.