Electromagnetic excitations in nuclei: from photon scattering to photodisintegration

In explosive nucleosynthesis temperatures are high enough for photodisintegration reactions to occur, e.g. leading to the production of p-process nuclei. In order to understand the reaction rates of element production and element disruption we started an experimental program at the new bremsstrahlung facility of the superconducting electron accelerator ELBE of FZ Dresden-Rossendorf. The bremsstrahlung facility and the detector setup are designed such that the scattering of photons from nuclei and the photodisintegration of nuclei around the particle separation energies can be studied under optimized background conditions. In activation measurements with bremsstrahlung at end-point energy from 10.0 to 16.5 MeV (g ,p), (g ,n) and (g ,a) reactions of 92,100Mo have been studied. Our activation yields can be described within a factor 2-3 or better with calculations using the cross sections from recent Hauser-Feshbach models.