Constraining the Synthesis of the Lightest p Nucleus ^{74}Se

We provide the first experimental cross section of the ^{73}As(p,γ)^{74}Se reaction to constrain one of the main destruction mechanisms of the p nucleus ^{74}Se in explosive stellar environments. The measurement was done using a radioactive ^{73}As beam at effective center-of-mass energies of 2.9 and 2.3  MeV/nucleon. Along with the total cross-section measurement, statistical properties of the ^{74}Se compound nucleus were extracted, constraining the reaction cross section in the upper Gamow window of the γ process. The impact of the experimentally constrained reaction rate on ^{74}Se production in Type II supernovae was investigated through Monte Carlo one-zone network simulations. The results indicate that the overproduction of ^{74}Se by Type II supernova models cannot be resolved by nuclear physics alone and point toward the need for a more detailed understanding of the astrophysical conditions of relevance for the γ process.