Nuclear Weak Rates for Astrophysical Processes in Stars

Toshio Suzuki,Satoshi Chiba,Naofumi Tsunoda,A Baha Balantekin,Takashi Yoshida,Yusuke Tsunoda,Toshitaka Kajino,Noritaka Shimizu,Michio Honma

doi:10.7566/jpscp.31.011039

Abstract

We have updated nuclear weak rates relevant to the study of astrophysical processes in stars. Neutrino-induced reaction cross sections, electron-capture and β-decay rates at stellar environments are obtained with new shell-model Hamiltonians that prove to be successful in describing spin responses — Gamow-Teller and spin-dipole transitions — in nuclei. The cross sections and rates are applied to nucleosynthesis in supernovae, detection of ν and nuclear URCA processes.

Highlights

We have updated nuclear weak rates which are important to the study of astrophysical processes in stars. ν-nucleus reaction cross sections on 12C [1], 13C [2], 16O [3], 40Ar [4], Fe, and 56Ni [5] have been updated and applied to nucleosynthesis in supernovae [1,3,5], ν detection [2,3,4] and study of ν properties such as mass hierarchies [6]
Neutrino-induced reactions on 12C and 13C at reactor and supernova ν energies are investigated by shell-model calculations with the SFO Hamiltonian, which can well reproduce the Gamow-Teller (GT) strength in 12C
Neutrino-nucleus reaction cross sections, e-capture and β-decay rates in stellar environments have been updated with the use of new shell-model Hamiltonians

Summary

Introduction

We have updated nuclear weak rates which are important to the study of astrophysical processes in stars. ν-nucleus reaction cross sections on 12C [1], 13C [2], 16O [3], 40Ar [4], Fe, and 56Ni [5] have been updated and applied to nucleosynthesis in supernovae [1,3,5], ν detection [2,3,4] and study of ν properties such as mass hierarchies [6]. We have updated nuclear weak rates which are important to the study of astrophysical processes in stars. Electron-capture and β-decay rates in pf-shell and sd-shell nuclei at stellar environments have been updated with GXPF1J [7] and USDB, respectively. They have been used to study synthesis of iron-group nuclei in type Ia supernovae [8], and nuclear. The rates for nuclei in the island of inversion with sd-pf shells are important for nuclear URCA processes in the neutron star crusts. 2. We discuss e-capture and β-decay rates in sd-shell and pf-shell nuclei in Sect. 3. The rates for neutron-rich nuclei, where two-major shells are involved, will be discussed in Sect.

Neutrino-nucleus Reaction Cross Sections on Light Nuclei

Electron-capture and β-decay Rates of Nuclei within One-major Shells

Electron-capture and β-decay Rates of Nuclei with Two-major Shells

Findings

Summary