Kim Tien Thanh

Measurement of isomeric yield ratios of 99m,g;101m,g;102m,gRh in the natPd(γ,pxn) reactions with the bremsstrahlung end-point energies of 50–70 MeV

The isomeric yield ratios of 99m,gRh, 101m,ggRh, and 102m,gRh isomeric pairs produced from the natPd(γ,pxn) reactions were measured with the bremsstrahlung end-point energies of 50-, 55-, 60-, 65-, and 70-MeV at the 100MeV electron linac of the Pohang Accelerator Laboratory, Korea. The measurements were carried out with the activation method in combination with off-line γ-ray spectrometry. In order to improve the accuracy of the activity measurements, the separation of the overlapping γ-rays and the necessary corrections for the counting losses were made. The new experimental results are compared with the theoretical values of the TALYS-1.6 code.

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

We identified eight radionuclides Au, Au, Au, Au, Au, Au, Au, Au formed via the multiple photoneutron reactions Au(γ, kn)197−kAu with 2.5 GeV bremsstrahlung. The yields of radionuclides that decay by emitting γ-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 197Au(γ,kn)197−kAu reaction yields according to incident bremsstrahlung energy and neutron multiplicity are also discussed.

Measurement of Thermal Neutron Capture Cross Section and Resonance Integral for the \(^{45}\)Sc\((n,\gamma)^{46}\)Sc Reaction with Pulsed Neutrons

Thermal neutron capture cross section and resonance integral for the 45Sc(n,γ)46Sc reaction were measured by the activation method using the 197Au(n,γ)198Au reaction as a single comparator. The high-purity scandium and gold samples with and without Cd cover with the thickness of 0.5 mm were irradiated in a pulsed neutron field of the 100 MeV electron linac of the Pohang Accelerator Laboratory (PAL). The induced activities in the activated foils were measured with a well calibrated HPGe detector. In order to improve the accuracy of the experimental results the effect of the non-ideal epithermal spectrum was taken in to account by determining the neutron spectrum shape factor (α), and the corrections for the thermal (Gth) and the resonance (Gepi) neutron self-shielding effects, the γ-ray attenuation (Fg) and the γ-ray coincidence summing effect were made. The thermal neutron cross-section for the 45Sc(n,γ)46Sc reaction has been determined to be σo = 27.6 ± 0.8 barn. By assuming the cadmium cut-off energy of 0.55 eV, the resonance integral for the 45Sc(n,γ)46Sc reaction has been determined to be Io = 12.7±0.7 barn. The present results are compared with the reference data and discussed.