Cross sections of low energy (p,γ) and (p,n)-reactions on selenium isotopes for the astrophysical γ-process

The cross sections of the proton radiative captures ⁷⁴Se(p, γ)⁷⁵Br, ⁷⁶Se(p, γ)⁷⁷Br, and ⁷⁷Se(p, γ)⁷⁸Br as well as the threshold ⁷⁷Se(p, n)⁷⁷Br and ⁸⁰Se(p, n)⁸⁰Br reactions have been measured in the astrophysical relevant energy range (up to 3.6 MeV) using the Kharkiv and Debrecen Van de Graaff accelerators and thin targets of enriched selenium isotopes. The activation technique using high resolution gamma spectrometry of reaction products was applied to determine the cross sections of the above reactions. Astrophysical S-factors and reaction rates were derived from the experimental values of the cross sections. The experimental data are compared with the earlier measurements if available and with the statistical theory predictions using the NON-SMOKER computer code with the standard parameter set. Good agreement was found in general.