Measurement of Thermal Neutron Capture Cross Section and Resonance Integral of the Reaction 133Cs(n, γ)134m,134gCs

Abstract

The measurements of the thermal neutron (2,200 m/s neutron) cross section (σ0) and the resonance integral (I 0) of the 133Cs(n, γ;) reaction were performed by an activation method to obtain fundamental data for research on the transmutation of nuclear wastes. The cross sections for the formations of the isomeric state 134mCs and the ground state 134mCs were measured respectively by following the behavior of the γ-ray counting rate after the irradiation.The thermal neutron capture cross sections and the resonance integrals of the 133Cs(n, γ) reaction were determined to be 2.70±0.13 b and 23.2±1.8 b for the formation of the isomeric state 134mCs, and 26.3±1.0 b and 275±16 b for the formation of the ground state of 134gCs. The results for the reaction 133Cs(n, γ)134m+gCs were 29.0±l.0 b and 298±16 b, respectively. As for the thermal neutron capture cross section for the formation of 134m+gCs, the evaluated value (29.00 b) of JENDL-3.2 agreed with the present result. The reported value by Baerg et al. was in good agreement with the present result within the limits of error on the thermal neutron capture cross section for 134mCs. On the other hand, the resonance integral for 134m+g Cs was 32% smaller than the experimental value by Steinnes et al.