Neutron capture cross sections of130,132,134,136,138Ba

Abstract

Cross sections for radiative capture of neutrons have been measured by the activation technique for stable isotopes of Ba with mass numbers 130, 132, 134, 136, and 138. From separate irradiations using thermal and epithermal neutrons, independent values for the thermal cross sections and effective resonance integrals have been determined. Improved values for the radioactive decay half-lives of ${}^{131}$Ba${}^{g}$, ${}^{131}$Ba${}^{m}$, ${}^{133}$Ba${}^{m}$, ${}^{135}$Ba${}^{m}$, and ${}^{139}$Ba were also obtained. Results of a new measurement of the energies and intensities of the \ensuremath{\gamma} rays in the decay of ${}^{139}$Ba are reported, along with \ensuremath{\beta} feedings and energies for the excited states in the daughter ${}^{139}$La.