Reactions rates of (p,n) and (α,n) reactions important to nucleosynthesis

The use of a 6 MV Van de Graaff accelerator for the studies of (p,n) and (α,n) reactions in intermediate mass nuclei is described with particular emphasis on the measurement of proton strength functions in the atomic-mass range from 88 to 124. The neutrons are detected in a 60-cm-diameter polyethylene sphere detector with an efficiency which is independent of energy for neutrons having energies between 30 keV and 2.5 MeV. In some cases, cross sections for the inverse reactions have been obtained using the principle of detailed balance. Nucleosynthesis reaction rates N_A (σv) have been determined in most cases. The (p,n) reaction studies are of interest in establishing reaction systematics for p-process nuclei.