Variation in the 64Ge(p;)65As reaction rates

We report on the variation in the 64Ge(p,γ)65As reaction rates due to uncertainties of either nuclear mass and level structure of the 65As isotope or non-resonant reaction rates. The change in the reaction rates is from a few factors to one order of magnitude due to the uncertainty of the non- resonant rates, which were calculated using the astrophysical S-factor and the statistical Hauser–Feshbach model. The mass uncertainty of the 65As nucleus (∆m = 85 keV) results in a variation of a few factors in the reaction rates at T9 = 1. At present, the estimated effective lifetimes of 64Ge in the rp-process are ranging from 0.5 to 162 ms. The results indicate that the resonance at Ex = 1.155 MeV and the Q-value of the reaction must be precisely determined to improve the accuracy of rp-process simulations.