A systematic investigation was carried out on ~aSIn to determine the contribution of different reactions to the total non-elastic cross-section in the 13.43 and 14.84 MeV incident neutron energy range. All the major components of aNE were measured with exception of the ~g(n, n') cross section. An analytical expression is recommended to estimate the aN~ data as a function of mass number at E, = 14.1 MeV. By the knowledge of aNE, the energy dependence of ag(n, n') could be deduced. The isomeric cross section ratios both for (n, 2n) and (n, n') processes were also determined in the given energy range. The present experiment proves the dependence of am/(~ ~ + a m) ratio on the spin value (I,,) of the isomeric state in the (n, 2n) reaction. Excitation functions of the (n, 2n), (n, n') (n, p) and (n: p, c~) reactions calculated by STAPRE code show good agreement with the experimental results.

Cross sections for the reactions 2VAl(n,p)2VMg and 28Si(n,p)ZSA1 were measured by activation method between 13.40 and 14.83 MeV neutron energy. An accuracy of about 4% was achieved using the 27Al(n, 7)14Na reaction as a reference at 14.1 MeV where the relative excitation function has also been measured. Results obtained were compared to a recent compilation and that calculated by the Hauser-Feshbach model. Using the back-shifted level density formula and taking into account the contribution of the separated levels, the calculations were extended to the energy range from the threshold to 18 MeV. A structure was observed in the 2VAl(n, c~)24Na reaction cross section curve around 14 MeV neutron energy.