Abstract
Background: The anomalous Ne22 abundance measured in certain presolar graphite grains is thought to arise from the decay of Na22 that was synthesized at high temperatures in core-collapse supernovas. To better interpret this abundance anomaly, the primary destruction mechanism of Na22, the Na22(p,γ)Mg23 reaction, must be better understood. Purpose: Determine proton branching ratios of several Mg23 excited states that play a role in the high-temperature Na22(p,γ)Mg23 reaction rate. Methods: Particle decays of Mg23 excited states populated with the previously reported Mg24(p,d)Mg23 transfer reaction measurement [Kwag, Eur. Phys. J. A 56, 108 (2020)EPJAFV1434-600110.1140/epja/s10050-020-00106-y] were analyzed to extract proton branching ratios. The reaction was studied using a 31-MeV proton beam from the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory and Mg24 solid targets. Results: Proton branching ratios of several Mg23 excited states in the energy range Ex=8.044-9.642 MeV were experimentally determined for the first time for the p0 and p1′ (p1+p2+p3) decay channels. Conclusions: These new branching ratios for Mg23 levels can provide an experimental foundation for an improved high-temperature rate of the Na22(p,γ)Mg23 reaction needed to understand production of anomalously high Ne22 abundance in core-collapse supernovas.
| Original language | English |
|---|---|
| Article number | 025801 |
| Journal | Physical Review C |
| Volume | 105 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 2022 |
Funding
This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT) (Grants No. 2013M7A1A1075764, No. 2016R1A5A1013277, and No. 2020R1A2C1005981). Additionally, the research was supported in part by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through the U.S. DOE Cooperative Agreement No. DE-FG52-08NA28552 with Rutgers University and Oak Ridge Associated Universities. This work was also supported in part by the Office of Nuclear Physics, Office of Science of the U.S. DOE under Contract No. DE-FG02-96ER40955 with Tennessee Technological University, Contract No. DE-FG02-96ER40983 with the University of Tennessee, and Contract No. DE-AC-05-00OR22725 with Oak Ridge National Laboratory; by the National Science Foundation under Contract No. PHY-2011890 with University of Notre Dame and Contract No. PHY-1812316 with Rutgers University; and by the Institute for Basic Science (Grant No. IBS-R031-D1).