Neutrino Oscillation Effects on Supernova Light‐Element Synthesis

Abstract

Neutrino oscillations affect light-element synthesis through the ν-process in supernova explosions. The 7Li and 11B yields produced in a supernova explosion of a 16.2 M ⊙ star model increase by factors of 1.9 and 1.3 in the case of the large mixing angle solution with a normal mass hierarchy and sin22θ 13 ≳ 2 × 10-3 compared with those without the oscillations. In the case of an inverted mass hierarchy or a nonadiabatic 1-3 mixing resonance, the increment of their yields is much smaller. Neutrino oscillations raise the reaction rates of charged-current ν-process reactions in the region outside oxygen-rich layers. The number ratio of 7Li/11B could be a tracer of a normal mass hierarchy and a relatively large θ 13, still satisfying sin22θ 13 ≤ 0.1, through future precise observations in stars having strong supernova components.