Determination of the 74Ge(p,γ)75As reaction rates in p-process nucleosynthesis with in-beam γ spectroscopy

Abstract The 74Ge( p , γ )75As reaction is believed to have a strong effect on the production of the lightest p-nucleus 74Se. The 74Ge( p , γ )75As reaction cross sections were measured in the range of E p = 2.5-4.3 MeV with an in-beam γ spectroscopy method at the 3 MV tandem accelerator of the Institute of Nuclear Science and Technology, Sichuan University. The experimental results show good agreement with previous works, and extend the measurements to the widest energies to date combined with our latest work at the 1.7 MV tandem accelerator of China Institute of Atomic Energy. Our new cross sections are compared with theoretical predictions using the TALYS and EMPIRE nuclear reaction codes. The EMPIRE-EGSM calculation presents the best description of all the experimental data, and was used to derive the reaction rates. The present rates are significantly higher than the REACLIB compilation by a factor of up to 47% within the p-process relevant temperatures.