We have measured the cross section of the 83 Rb ( p , γ ) 84 Sr radiative capture reaction in inverse kinematics using a radioactive beam of 83 Rb at incident energies of 2.4 and 2.7 A MeV. Prior to the radioactive beam measurement, the 84 Kr ( p , γ ) 85 Rb radiative capture reaction was measured in inverse kinematics using a stable beam of 84 Kr at an incident energy of 2.7 A MeV. The effective relative kinetic energies of these measurements lie within the relevant energy window for the γ process in supernovae. The central values of the measured partial cross sections of both reactions were found to be 0.17 – 0.42 times the predictions of statistical model calculations. Assuming the predicted cross section at other energies is reduced by the same factor leads to a slightly higher calculated abundance of the p nucleus 84 Sr , caused by the reduced rate of the 84 Sr ( γ , p ) 83 Rb reaction derived from the present measurement.
Physical Review C
Physics & Astronomy
Williams, M.; Davids, B.; Lotay, G.; Nishimura, N.; Rauscher, T.; Gillespie, S. A.; Alcorta, M.; Amthor, Alan M.; Ball, G. C.; Bhattacharjee, S. S.; Bildstein, V.; Catford, W. N.; Doherty, D. T.; Esker, N. E.; Garnsworthy, A. B.; Hackman, G.; Hudson, K.; Lennarz, A.; Natzke, C.; Olaizola, B.; Psaltis, A.; Svensson, C. E.; Williams, J.; Walter, D.; and Yates, D.. "Cross Sections of the 83Rb (p,γ)84Sr and 84Kr(p,γ)85Rb Reactions at Energies Characteristic of the Astrophysical γ Process." (2023) : 035803.