CROSS-SECTIONS OF PHOTONUCLEAR REACTIONS ON natМо TARGETS AT END-POINT BREMSSTRAHLUNG ENERGY UP TO Еγmax = 100 МeV

Experiments to determine the yields and bremsstrahlung flux-averaged cross-sections σ(Еγmax) of photonuclear reactions on the natural Mo targets were performed on the beam from the electron linear accelerator LUE-40 with the use of the γ-activation technique. The bremsstrahlung end-point energies were in the range Еγmax = 35…80 MeV. The bremsstrahlung quantum flux was calculated with the program GEANT4.9.2 and, in addition, was monitored using the 100Мо(γ, n)99Мо reaction. Calculations of the yields and average cross-sections σ(Еγmax) for photonuclear reactions on stable Mo isotopes were computed using the σ(Е) cross-sections from the TALYS1.95 code (for the level density model LD1). A comparison of experimental and calculated cross-sections σ(Еγmax) for reactions 92Мо(γ, 2n)90Мо and 92Мо(γ, pn)90Nb was performed.

Study of Multiple Photoneutron Reactions on 197Au Induced by 2.5 GeV Bremsstrahlung

We identified eight radionuclides \(^{196}\)Au, \(^{195}\)Au, \(^{194}\)Au, \(^{193}\)Au, \(^{192}\)Au, \(^{191}\)Au, \(^{190}\)Au, \(^{189}\)Au formed via the multiple photoneutron reactions \(^{197}\)Au\((\gamma ,kn)^{197 - k}\)Au with 2.5 GeV\break bremsstrahlung. The yields of radionuclides that decay by emitting \(\gamma \)-ray were measured using high purity germanium (HPGe) detector coupled to a PC-based multichannel analyzer. In order to improve the accuracy of the experimental results the necessary corrections were made. The obtained results are compared with reference data and the variations of the \(^{197}\)Au(\(\gamma \),kn)\(^{197 - k}\)Au reaction yields according to incident bremsstrahlung energy and neutron multiplicity are also discussed.