Measurement of the 6Li(n, absorption) and 10B(n, absorption) cross sections by the shell transmission method

Abstract

The spherical shell transmission method was used to measure the total neutron absorption cross sections for 10B from 10·7 to 247 keV and for 6Li from 10·7 to 102 keV. For 6Li the absorption cross section could be equated directly to the (n, α) cross section. In the case of 10B, the absorption cross section may contain a weak component due to the (n, t) reaction in addition to the (n, α) reaction. The 10B(n, α) measurement near 10 keV are in good agreement with a 1/ ν extrapolation from the thermal cross section. The 6Li(n, α) results near 10 keV are ∼30% higher than a 1/ ν extrapolation from the thermal cross section and are in agreement with some earlier work but are in disagreement with recent measurements of Bergman and Shapiro and of Schwarz, Stromberg and Bergstrom both of which are consistent with a 1/ ν extrapolation.