Li6(n, α)H3Cross Section as a Function of Neutron Energy

The total ${\mathrm{Li}}^6(n, \alpha ){\mathrm{H}}^3$ cross section has been measured absolutely over the range of neutron energies from 0.88 to 14.1 Mev, with errors varying from 11 to 18%. At its low-energy end, the curve $\sigma \left(E_n\right)$ joins smoothly with an extension of the curve of earlier data of Blair and Holland, for which the maximum neutron energy was 0.62 Mev. A log-log plot of $\sigma \left(E_n\right)$ for the present data shows a variation approximately as ${E_n}^{-1\mathrm{}}$ for the high-energy portion of the curve with a break to greater flatness at the lower energies, resulting in a broad hump in the cross-section curve at about 2 Mev. This hump is believed to be due to competition from deuteron-producing reactions.