Measurement of half-lives for Y-87m,Y-g and Au-196m,Au-g,Au-194 produced from the photon and neutron induced reactions of Y-89 and Au-197

摘要

We have measured the half-lives of Y-87m and Y-87g produced from the Y-89(gamma, 2n) and Y-89(n, 3n) reactions with the bremsstrahlung end-point energy of 65MeV and the average neutron energy of 37.2MeV using an activation and an off-line gamma-ray spectrometric technique, respectively. The bremsstrahlung photon was produced by using the 100MeV electron linac of the Pohang Accelerator Laboratory (PAL), whereas the fast neutron was produced from the Be-9(p, n) reaction by using the 45MeV proton of the MC-50 Cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS). We have also measured the half-lives of Au-194 and Au-196m2,Au-g produced from the Au-197(gamma, xn; x=1, 3) and Au-197(n, xn; x=2, 4) reactions with the bremsstrahlung end-point energy of 60MeV and the average neutron energy of 37.2MeV using the same technique and the same facilities as mentioned above. The induced gamma-ray activities of the irradiated samples were measured by using an energy- and efficiency calibrated high purity germanium (HPGe) detector. The spectrum analysis has been done by using the ROOT software to separate signals from background. The measured half-lives are compared with the literature values and are in general agreement with each other within the uncertainties.