Measurement of key resonances for the Al-24(p,gamma)Si-25 reaction rate using in-beam gamma-ray spectroscopy

作者：Longfellow B^*; Gade A; Brown B A; Richter W A; Bazin D; Bender P C; Bowry M; Elman B; Lunderberg E; Weisshaar D; Williams S J

来源：PHYSICAL REVIEW C, 2018, 97(5): 054307.

DOI：10.1103/PhysRevC.97.054307

Energy levels and branching ratios for the rp-process nucleus Si-25 were determined from the reactions Be-9(Si-26, Si-25) X and Be-9(Al-25, Si-25) X using in-beam gamma-ray spectroscopy with both high-efficiency and high-resolution detector arrays. Proton-unbound states at 3695(14) and 3802(11) keV were identified and assigned tentative spins and parities based on comparison to theory and the mirror nucleus. The Al-24(p,gamma)Si-25 reaction rate was calculated using the experimental states and states from charge-dependent USDA and USDB shell-model calculations with downward shifts of the 1s(1/2) proton orbital to account for the observed Thomas-Ehrman shift, leading to a factor of 10-100 increase in rate for the temperature region of 0.22 GK as compared to a previous calculation. These shifts may be applicable to neighboring nuclei, impacting the proton capture rates in this region of the chart.

• 出版日期2018-5-4