Activation measurements of fast neutron radiative capture for 139La

The neutron capture cross section of the neutron magic isotope 139La has been measured relative to that of 27Al by means of the activation method. The fast neutrons were produced via the 3H(d,n)4He reaction on Pd-300 neutron generator. The natural high-purity La2O3 powder was used as target material. Induced gamma activities were measured by a high-resolution gamma-ray spectrometer with high-purity germanium (HPGe) detector. Measurements were corrected for gamma-ray attenuations, random coincidence (pile-up), dead time and fluctuation of neutron flux. The new values for En=13.5±0.2, 14.1±0.2, and 14.8±0.2 MeV are found to be 1.30±0.08, 1.15±0.08 and 0.99±0.07 mb, respectively. Results were discussed and compared with some corresponding values found in the literature.

► D–T neutron source was used to measure cross sections using activation method.
► 27Al(n,α)24Na was used as the monitor for the measurement.
► The cross sections for the (n,γ) reactions on neutron magic isotope 139La have been measured.
► The data for 139La(n,γ)140La reaction are presented.
► The results were compared with previous data and with evaluation data.