Speaker
Description
There is a growing consensus in recent multi-messenger astronomy that the explosions of single massive stars, i.e. supernovae (SNe) and collapsars, dominate the heavy-element production over the entire history of cosmic evolution, while the neutron-star mergers could contribute only partly in the recent epoch because of long time-delay due to slow GW radiation [1]. We will first discuss when and how these different astrophysical sites have contributed to the enrichment of the heavy elements in the universe. We have recently found that the i- and s-processes as well as r-process could occur in collapsar nucleosynthesis, raising the importance of (n, γ) reactions on unstable nuclei near the stability line [2]. These explosive phenomena emit extremely large flux of energetic neutrinos that provide unique nucleosynthetic signals of the ν-nucleus interactions at high densities. We will, secondly, discuss how the ν-induced nucleosynthesis, named ν-process, competes with γ-process in the production of 138La, 180Ta, 92Nb, 98Tc, 11B, 7Li, etc. by taking account of the flavor oscillations due to the self-interaction and MSW effect. We here propose a new sensitive nuclear astrophysics method to constrain still unknown neutrino mass hierarchy [3]. The νp-process is shown to explain extremely abundant p-nuclei like 92,94Mo and 96,98Ru [4] whose origin has long been unsolved since B2FH in 1957. Throughout these discussions, we will highlight the critical nuclear physics relevant for the stellar nucleosynthesis at finite temperature and density [5].
[1] Y. Yamazaki, Z. He, T. Kajino, et al., ApJ 933 (2022), 112.
[2] Z. He, et al. with T. Kajino, ApJ Lett. 966 (2024), L37; PRL (2025), submitted.
[3] X. Yao, Y. Luo, T. Kajino, et al., ApJ 980 (2025) 247; CPC (2025),in press.
[4] H. Sasaki, Y. Yamazaki, T. Kajino, et al., ApJ 924 (2022), 29; PL B851 (2024), 138581.
[5] X. Wang, B. Sun, T. Kajino, et al. ApJ 984 (2025), 8.
| Presentation mode | Onsite |
|---|
