Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

The nat Mo(γ, x n)90,91,99 Mo reaction cross-sections were experimentally determined for the bremsstrahlung end-point energies of 12, 14, 16, 45, 50, 55, 60 and 70 MeV by activation and off-line gamma-ray spectrometric technique and using the 20 MeV electron linac (ELBE) at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany, and the 100 MeV electron linac at the Pohang Accelerator Laboratory (PAL), Pohang, Korea. The nat Mo(gamma, x n)88,89,90,91,99 Mo reaction cross-sections as a function of photon energy were also calculated using the computer code TALYS 1.6. The flux-weighted average cross-sections were obtained from the literature data and the calculated values of TALYS based on mono-energetic photons and are found to be in general agreement with the present results. The flux-weighted average experimental and theoretical cross-sections for the nat Mo(γ, x n)88,89,90,91,99 Mo reactions increase with the bremsstrahlung end-point energy, which indicates the role of excitation energy. After a certain energy, the individual nat Mo(gamma, x n) reaction cross-sections decrease with the increase of bremsstrahlung energy due to opening of other reactions, which indicates sharing of energy in different reaction channels. The 100 Mo(gamma, n) reaction cross-section is important for the production of 99 Mo, which is a probable alternative to the 98 Mo(n, gamma) and 235 U(n, f) reactions.