Cross Section Measurements of56Fe(n, p)56Mn,63Cu(n, 2n)62Cu and65Cu(n, 2n)64Cu between 14 and 19 MeV

The cross-sections for the reactions 56 Fe(n, p) 56 Mn, 63 Cu(n, 2n) 62 Cu and 65 Cu(n, 2n) 64 Cu for neutron energies from 14 to 19 MeV were measured by the activation technique, using a proton recoil telescope to determine the neutron flux. The uncertainties, ranging from 2 to 6%, were estimated at approximately the 99% confidence level. Less accurate measurements of the 54 Fe(n, 2n) 53 Fe, 65 Cu(n, p) 65 Ni and 65 Cu(n, nα) 61 Co cross-sections were also made. A detailed account of the experimental procedure is given, and the results are compared with several recent evaluations. No fine structure was observed in the 56 Fe(n, p) 56 Mn cross-section over the range from 17.5 to 17.9 MeV. The half-life of 62 Cu was found to be 9.73 ± 0.06 min, where the uncertainty is approximately at the 99% confidence level. The measured 56 Fe(n, p) 56 Mn cross-section will be used as a secondary standard at the NPL for determining monoenergetic neutron flux densities from 14 to 19 MeV by the activation technique.