EXCITATION CURVES FOR THE REACTIONS Fe⁵⁶(<i>n</i>, <i>p</i>)Mn⁵⁶ AND Co⁵⁹(<i>n</i>, α)Mn⁵⁶

Abstract

Excitation curves for the reactions Fe 56 (n, p)Mn 56 and Co 59 (n, α)Mn 56 have been measured by the activation method from near threshold energies to 20.3 Mev. The measurements are relative to the known cross section for the S 32 (n, p)P 32 reaction. Cross sections for both reactions increase smoothly with neutron energy and reach maximum values of 119 ± 4 mb for the Fe 56 (n, p) reaction at 13.6 Mev and 30.0 ± 0.9 mb for the Co 59 (n, α) reaction at 14.5 Mev. Above 15 Mev both cross sections decrease with neutron energy. From the excitation curves effective cross-section values for a fission-neutron spectrum have been calculated as 1.04 ± 0.05 mb for the (n, p) reaction and 0.140 ± 0.007 mb for the (n, α) reaction.