Level structure of 21Mg and the 20Na(p, γ)21Mg stellar reaction rate

S. Kubono, Y. Funatsu, N. Ikeda, M. Yasue, T. Nomura, Y. Fuchi, H. Kawashima, S. Kato, H. Miyatake, H. Orihara, T. Kajino

Research output: Contribution to journalArticlepeer-review

16 Citations (Scopus)


The nuclear level structure of 21Mg has been studied by the 24Mg(3He, 6He)21Mg reaction at 74 MeV. Angular distributions of the three-nucleon transfer reaction (3He, 6He) are measured for the first time, and successfully analyzed with exact finite-range distorted-wave-Born-approximation calculations, giving clear transferred angular momentum assignments. More than 20 states have been identified with excitation energy and spin-parity determinations, including a possible s-wave resonance just above the proton threshold. One of the s-wave resonances assumed in the previous stellar reaction rate estimates is found to be a bound state. The stellar reaction rate of the 20Na(p, γ)21Mg process is estimated using the experimental data. The results predict the ignition of the proton radiative-capture process at T = 1×108K under typical nova conditions (hydrogen density, XHρ{variant} = 5×105 g/cm3). This temperature happens to be in agreement with the previous theoretical estimates, but the new reaction rate is a few orders of magnitude smaller than the previous predictions for T {reversed tilde equals} 2-10×108K. The results also suggest that the nucleosynthesis flow of the rapid-proton process will run up to 21Mg immediately after breakout from the hot-CNO cycle.

Original languageEnglish
Pages (from-to)153-166
Number of pages14
JournalNuclear Physics, Section A
Issue number1-2
Publication statusPublished - Feb 1992
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics


Dive into the research topics of 'Level structure of 21Mg and the 20Na(p, γ)21Mg stellar reaction rate'. Together they form a unique fingerprint.

Cite this