Neutron capture cross section measurement for the ¹³⁹La(n,γ)¹⁴⁰La reaction at 0.0372 eV

Abstract

The thermal neutron capture cross section of the 139La(n,γ)140La nuclear reaction at 0.0372 eV energy was measured by the Neutron Diffraction Facility (NDF) in the Es-Salam Nuclear Research Reactor (Algeria). The 197Au(n,γ)198Au reaction was adopted as reference for the Neutron Activation Analysis (NAA). The induced activities in sample and control foils were measured non-destructively by a high-resolution HPGe γ-ray detector. The capture cross section of σ(∼7.5 ± 0.37) b was measured for the first time at this energy after correction for the γ attenuation effect. Our measured value at an energy of 0.0372 eV energy was compared with the evaluated cross sections reported in two different neutron databases, namely ENDF/B-VIII.0 and JENDL-5. The data measured at this energy was extrapolated to the energy 0.0253 eV, assuming 1/ν dependence in the thermal energy region, and the result was compared with the fully measured and evaluated values reported in the literature.