First Direct Measurement of an Astrophysical p-Process Reaction Cross Section Using a Radioactive Ion Beam

We have performed the first direct measurement of the ^{83}Rb(p,γ) radiative capture reaction cross section in inverse kinematics using a radioactive beam of ^{83}Rb at incident energies of 2.4 and 2.7A  MeV. The measured cross section at an effective relative kinetic energy of E_{cm}=2.393  MeV, which lies within the relevant energy window for core collapse supernovae, is smaller than the prediction of statistical model calculations. This …