A simultaneous evaluation of some important cross sections at 14.70 MeV

A simultaneous evaluation of the 27Al(n, α), 56Fe(n, p), 63Cu(n, 2n), 65Cu(n, 2n), 197Au(n, 2n), 93Nb(n, 2n), 32S(n, p), 1H(n, n), 27Al(n, p), 59Co(n, α), 235U(n, f) and 238U(n, f) cross sections at an energy of 14.70 MeV has yielded a consistent set with uncertainties (1-σ) of 0.5 - 1.5 % together with a correlation matrix. The large number of experimental results included were either ratio measurements or 'absolute' measurements relying on neutron fluences determined by the associated particle technique. The method of weighted least-squares, taking into account correlations, was used in the simultaneous evaluation. Good agreement was found with several recent evaluations. The effects of fine structure in 14 MeV cross sections need further investigation. (author) 242 refs., 12 figs., 11 tabs