Extraction of Nuclear Level Densities and gamma-ray strength functions for the ⁸⁵Rb compound nucleus relevant to the p- process

There are 35 proton-rich stable isotopes, known as p-nuclei. Their existence is attributed to the p-process, which primarily consists of a network of photodisintegration reactions on s- and r-process seed nuclei. The abundances of p-nuclei can be obtained based on simulations of this network, with most of the isotopes involved being radioactive. For this reason, direct measurements of these reactions are challenging, thus reaction rates are often obtained via theoretical models. Here we focus, not only on reaction cross section measurements of specific reactions, but also on extracting statistical properties such as the nuclear level density (NLD) and the gamma-ray strength function (gSF). Measurement of the ⁸⁴Kr(p,γ)⁸⁵Rb proton capture reaction has been performed with the SuN detector at the NSCL at MSU. A stable ⁸⁴Kr beam was impinged on to a hydrogen gas target in the energy range 2.7 MeV/u to 3.7 MeV/u. In the present work, a systematic investigation was performed to obtain the NLD and gSF for the ⁸⁵Rb compound nucleus. The RAINIER code was implemented to simulate the statistical de-excitation of the ⁸⁵Rb compound nucleus using various combinations of NLD and gSF. The resulting simulated spectra were compared to the experimental data to identify suitable combinations of NLD and gSF.