Systematic study of proton capture reactions in medium-mass nuclei relevant to the p process: The case of ¹⁰³Rh and ^113,115In

The cross sections of the ¹⁰³Rh(p,γ ) ¹⁰⁴Pd and the ^113,115In(p,γ ) ^114,116Sn reactions have been determined from γ angular distribution measurements carried out at beam energies from 2 to 3.5 MeV. An array of four highly efficient HPGe detectors all shielded with BGO crystals for Compton background suppression was used. Astrophysical S factors and reaction rates were deduced from the measured cross sections. Statistical model calculations were performed using the Hauser-Feshbach (HF) code TALYS and were compared with the new data. A good agreement between theory and experiment was found. In addition, the effect of different combinations of the nuclear input parameters entering the HF calculations on the ground-state reaction rates was investigated. It was found that these rates differ by a factor 3 at the most, being thus within the average discrepancies observed between calculated p-nuclei abundances and observations, if certain combinations of optical model potentials, nuclear level densities, and γ -ray strength functions are used.