Measurements of ⁶Li and ⁷Li Neutron-Induced Tritium Production Cross Sections at 15 MeV

Tritium production cross sections have been inferred from direct measurements of tritium generated in wafers of ⁶LiH and ⁷LiH under bombardment by 15-MeV neutrons produced at the Lawrence Livermore National Laboratory's Rotating Target Neutron Source-I facility. Sealed in a thin-walled lead container, each hydride wafer was immersed in boiling mercury that first amalgamated the lead and then dissociated the LiH. The hydrogen, acting as a carrier, was directed to an electronic counter and mixed carefully with methane. The counting procedure provided an accurate measure of tritium originally generated in each wafer. The TART Monte Carlo code was employed in the analysis of the data. The tritium production cross section for ⁶Li exposed to 14.92-MeV neutrons is 32 ±3 mb and that for ⁷Li exposed to 14.94-MeV neutrons is 302 ± 18 mb.