Supernova Nucleosynthesis, Radioactive Nuclear Reactions and Neutrino-Mass Hierarchy

Xingqun Yao,Motohiko Kusakabe,Silvio Cherubini,Seiya Hayakawa,Hidetoshi Yamaguchi,Toshitaka Kajino,W Liu,Y Wang,S Zeng,B Guo,X Tang

doi:10.1051/epjconf/202226001007

Abstract

The ν-process nucleosynthesis in core-collapse supernovae is a sensitive probe of unknown neutrino mass hierarchy through the MSW effect. We carefully studied the uncertainties of almost one hundred ν-induced and nuclear reactions associated with the nucleosynthesis and found that the ν-16O and 11C(α,p)14N reactions among them have the biggest effect on the final 7Li/11B isotopic abundance ratio. The neutrino mass hierarchy is constrained in our nucleosynthetic method with measured 7Li/11B value in SiC-X presolar grains. The inverted hierarchy is statistically more favored at the 2-σ C.L. [1].

Highlights

Core-collapse supernova (CCSN) ejects a huge number of three-flavour neutrinos and antineutrinos which provide observational signals through the Mikheyev–Smirnov–Wolfenstein (MSW) matter effect [2, 3]
The isotopic abundances in CCSNe are the very unique and sensitive probe of the neutrino mass hierarchy. Both 7Li and 11B were discovered [8] in presolar silicon-carbide X (Si-C X) grains which form from the supernova (SN) ejecta
We studied the sensitivity of the final yields to the 91 nuclear reactions

Summary

Introduction

Core-collapse supernova (CCSN) ejects a huge number of three-flavour neutrinos and antineutrinos which provide observational signals through the Mikheyev–Smirnov–Wolfenstein (MSW) matter effect [2, 3]. The energy spectra of three-flavor neutrinos vary as a function of radius depending on the mass hierarchy. These neutrinos interact with abundant nuclei in each layer, and various isotopes such as 7Li, 11B, 19F, 92Nb, 98Tc, 138La, 180Ta, etc. The isotopic abundances in CCSNe are the very unique and sensitive probe of the neutrino mass hierarchy. Both 7Li and 11B were discovered [8] in presolar silicon-carbide X (Si-C X) grains which form from the supernova (SN) ejecta. We discuss how to constrain the neutrino-mass hierarchy by comparing our theoretical prediction with the measured 7Li/11B ratio in the presolar Si-C X grains [1]

Supernova Model

Result and Discussions

Sensitivity to the nuclear reactions

Findings

Conclusion