New experimental 23Na(α,p)26Mg Reaction Rate for Massive Star and Type-Ia Supernova models

J. Hubbard, N.; Aa. Diget, C.; P. Fox, S.; O. U. Fynbo, H.; M. Howard, A.; S. Kirsebom, O.; M. Laird, A.; Munch, M.; Parikh, A.; Pignatari, M.; R. Tomlinson, J.

Abstract

The 23Na(α,p)26Mg reaction has been identified as having a significant impact on the nucleosynthesis of several nuclei between Ne and Ti in type-Ia supernovae, and of 23Na and 26Al in massive stars. The reaction has been subjected to renewed experimental interest recently, motivated by high uncertainties in early experimental data and in the statistical Hauser-Feshbach models used in reaction rate compilations. Early experiments were affected by target deterioration issues and unquantifiable uncertainties. Three new independent measurements instead are utilizing inverse kinematics and Rutherford scattering monitoring to resolve this. In this work we present directly measured angular distributions of the emitted protons to eliminate a discrepancy in the assumptions made in the recent reaction rate measurements, which results in cross sections differing by a factor of 3. We derive a new combined experimental reaction rate for the 23Na(α,p)26Mg reaction with a total uncertainty of 30% at relevant temperatures. Using our new 23Na(α,p)26Mg rate, the 26Al and 23Na production uncertainty is reduced to within 8%. In comparison, using the factor of 10 uncertainty previously recommended by the rate compilation STARLIB, 26Al and 23Na production was changing by more than a factor of 2. In type-Ia supernova conditions, the impact on production of 23Na is constrained to within 15%.

Citation

J. Hubbard, N., Aa. Diget, C., P. Fox, S., O. U. Fynbo, H., M. Howard, A., S. Kirsebom, O., …R. Tomlinson, J. (2021). New experimental 23Na(α,p)26Mg Reaction Rate for Massive Star and Type-Ia Supernova models. The Astrophysical journal, 912(1), Article 59. https://doi.org/10.3847/1538-4357/abee91

• Journal Article Type: Article
• Acceptance Date: Mar 11, 2021
• Online Publication Date: May 5, 2021
• Publication Date: May 1, 2021
• Deposit Date: Mar 20, 2021
• Publicly Available Date: May 10, 2021
• Journal: The Astrophysical journal
• Print ISSN: 0004-637X
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 912
• Issue: 1
• Article Number: 59
• DOI: https://doi.org/10.3847/1538-4357/abee91
• Keywords: Nuclear astrophysics; Nucleosynthesis; Carbon burning; Stellar nucleosynthesis; Nuclear physics; Nuclear reaction cross sections
• Public URL: https://hull-repository.worktribe.com/output/3742893