Measurement of thermal neutron capture cross section and resonance integral of the 138Ba(n, γ)139Ba reaction using 55Mn(n, γ)56Mn as a monitor

The thermal neutron capture cross section (σo) and the resonance integral cross section (Io) of the 138Ba(n, γ)139Ba reaction have been measured by the activation method using the Ghana Research Reactor-1 (GHARR-1). The barium and manganese targets were irradiated within and without a cadmium capsule. The result of the thermal neutron capture cross section for the 138Ba(n, γ)139Ba reaction is 0.53 ± 0.01barns. The result was obtained relative to the reference value 13.2 barns of the 55Mn(n, γ)56Mn reaction. The resonance integral cross section for the 138Ba(n, γ)139Ba reaction was also measured relative to the reference value of 13.9 barns for the 55Mn(n, γ)56Mn reaction. The present resonance integral cross section for the 138Ba(n, γ)139Ba reaction is 0.380 ± 0.005 barns. The previous measurements of the σo and Io of the reaction 138Ba(n, γ)139Ba were reviewed and the difference between the present values and the previous results were discussed. The present work was undertaken with the aim to contribute to the experimental basis of σo and Io evaluations.