Photodisintegration studies on the p-nuclei 92Mo and 144Sm for the astrophysical p-process

In burning stellar environments like supernova explosions, the temperatures are high enough for the production of heavy neutron deficient nuclei, the so-called p-nuclei. These are thought to be produced in such explosive scenarios either through chains of photodisintegration reactions on heavy seed nuclei. The modelling of the nucleosynthesis for the p-nuclei is mainly based on statistical model calculations. In this context, the knowledge of the experimental cross sections for the prediction of the p-nuclei abundances is of crucial importance and to forward in this direction we have started and experimental program at the bremsstrahlung facility of the superconducting electron accelerator ELBE of FZ Dresden-Rossendorf . Photodisintegration measurements on the astrophysically relevant p-nuclei 92Mo and 144Sm have been performed via photoactivation technique with bremsstrahlung end-point energies from 10.0 to 16.5 MeV. In particular the (gamma,alpha) reactions of the mentioned nuclei were studied for the first time at different endpoint energies above and close to the threshold. The bremsstrahlung facility and the experimental area are deigned so as to facilitate the studies under optimized background conditions. To probe the fascinating investigations on short-lived nuclei a new pneumatic delivery system has been built recently. First experiments on the short-lived decays following the reaction 144Sm(gamma,n) is discussed. The activation yields from all measurements are compared with calculations using cross sections from recent Hauser-Feshbach models .