Spin assignments for levels and the astrophysical reaction

M. S. Kwag; K. Y. Chae; S. Ahn; D. W. Bardayan; K. A. Chipps; J. A. Cizewski; M. E. Howard; R. L. Kozub; K. Kwak; B. Manning; M. Matos; P. D. O’Malley; S. D. Pain; W. A. Peters; S. T. Pittman; A. Ratkiewicz; M. S. Smith; S. Strauss

doi:10.1140/epja/s10050-020-00106-y

2023 Impact factor 2.6

Hadrons and Nuclei

Eur. Phys. J. A (2020) 56: 108
https://doi.org/10.1140/epja/s10050-020-00106-y

Regular Article – Experimental Physics

Spin assignments for $^{23}\hbox {Mg}$ levels and the astrophysical $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction

M. S. Kwag¹, K. Y. Chae¹^*, S. Ahn², D. W. Bardayan³, K. A. Chipps⁴, J. A. Cizewski⁵, M. E. Howard⁵, R. L. Kozub⁶, K. Kwak⁷, B. Manning⁵, M. Matos⁸, P. D. O’Malley⁵, S. D. Pain⁹, W. A. Peters¹⁰, S. T. Pittman⁹, A. Ratkiewicz⁵, M. S. Smith⁹ and S. Strauss⁵

¹ Department of Physics, Sungkyunkwan University, Suwon, 16149, South Korea
² Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee, 37996, USA
³ Department of Physics, University of Notre Dame, Notre Dame, IN, 46556, USA
⁴ Department of Physics, Colorado School of Mines, Golden, CO, 80401, USA
⁵ Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, 08903, USA
⁶ Department of Physics, Tennessee Technological University, Cookeville, TN, 38505, USA
⁷ Department of Physics, School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, South Korea
⁸ Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, 70803, USA
⁹ Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
¹⁰ Oak Ridge Associated Universities, Oak Ridge, TN, 37831, USA

^* e-mail: kchae@skku.edu

Received: 20 October 2019
Accepted: 18 February 2020
Published online: 6 April 2020

Abstract

The $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction is responsible for destruction of the long-lived radionuclide $^{22}\hbox {Na}$ produced during nova explosions. Since the reaction proceeds through resonances from levels in $^{23}\hbox {Mg}$ above the proton threshold at 7.581 MeV, the properties of these levels such as excitation energies, spins, and parities are crucial ingredients to determine the $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction rate. Despite recent studies of these levels, their spins are not well constrained in many cases. We have measured the $^{24}\mathrm{Mg}(p,d)^{23}\hbox {Mg}$ transfer reaction to determine spectroscopic properties of these levels at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The spin of the $E_{x}$ = 7.788 MeV level in $^{23}\hbox {Mg}$ is constrained to be $J^{\pi }$ = (3/2 $$^+$$ , 5/2 $$^+$$ ) through the present work. The astrophysical $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction rate at nova temperatures is updated accordingly. Nova nucleosynthesis model calculations using the newly updated $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction rate shows that the final weighted abundance of the radionuclide $^{22}\hbox {Na}$ is increased by 42% compared to that obtained by using the previous $^{22}\hbox {Na}(p,\gamma )^{23}\hbox {Mg}$ reaction rate of Sallaska et al. for a 1.35 $M_{\odot }$ ONeMg white dwarf.