MeV neutron production from thermal neutron capture in Li and B compounds

Production of fast neutrons from capture of thermal neutrons in various compounds of Li and B is measured and calculated. For several of the Li compounds the fast neutron yield per thermal neutron is found to be greater than 80 x 10-6, whereas for the B compounds it is less than 10-6. Enriched 6Li compounds produce on the average a factor of two lower yield of fast neutrons than compounds of natural Li. (orig.)