p-process nucleosynthesis via proton-capture reactions in thermonuclear supernovae explosions

Model calculations within the framework of the so-called. process show an underproduction of the p nucleus with the highest isotopic abundace Mo-92. This discrepancy can be narrowed by taking into account the alternative production site of a type Ia supernova explosion. Here, the nucleus Mo-92 can be produced by a sequence of proton-capture reactions. The amount of Mo-92 nuclei produced via this reaction chain is most sensitive to the reactions Zr-90(p,gamma) and Nb-91(p,gamma). Both rates have to be investigated experimentally to study the impact of this nucleosynthesis aspect on the long-standing Mo-92-problem. We have already measured the proton-capture reaction on Zr-90 using high-resolution in-beam gamma-ray spectroscopy. In this contribution, we will present our preliminary results of the total cross sections as well as the partial cross sections. Furthermore, we plan to measure the Nb-91(p,gamma) reaction soon. Due to the radioactive target material, the Nb-91 nuclei have to be produced prior to the experiment. The current status of this production will be presented in this contribution.