Flux weighted average cross-sections of natNi(γ, x) reactions with the bremsstrahlung end-point energies of 55, 59, 61 and 65 MeV

We measured the flux weighted average cross-sections of the natNi(γ,xn)56,57Ni and natNi(γ, pxn)55,56,57,58Co reactions with the bremsstrahlung end-point energies of 55, 59, 61 and 65 MeV by using an activation cum off-line γ-ray spectrometric technique at the Pohang Accelerator Laboratory (PAL), Korea. The natNi(γ, xn) and natNi(γ, pxn) reaction cross-sections as a function of monoenergetic photon were calculated theoretically by using the computer code TALYS-1.8. The flux-weighted average cross-sections of the natNi(γ, xn) and natNi(γ, pxn) reactions from the present work were compared with the similar data from the literature as well as the theoretical values from the TALYS-1.8 code and the TENDL-2015 data library. Both the experimental and theoretical values increase sharply from the reaction threshold to a maximum value where the next reaction channel opens. After the maximum value, individual reaction cross section decreases slowly with increase of bremsstrahlung end-point energy, which may be due to the opening of other possible reaction channels.