Measurements of activation cross sections of (n, p) and (n, α) reactions in the energy range of 3.5–5.9 MeV using a deuterium gas target

Activation cross sections of (n, p) and (n, α) reactions were measured by means of the activation method in the neutron energy range of 3.5–5.9 MeV using a deuterium gas target. The irradiated target isotopes were 27Al, 28,29Si, 41K, 51V, 61Ni, 65Cu, 64,67Zn, 69Ga, 79Br, 92Mo and 93Nb. The cross sections of the 29Si(n, p) 29Al, 67Zn(n, p) 67Cu, 69Ga(n, p) 69mZn, 79Br(n, p) 79mSe, and 69Ga(n, α) 66Cu reactions were obtained for the first time in the studied energy range. The d-D neutrons were generated by the deuterium gas target at the Van de Graaff accelerator (KN-VdG) at Nagoya University. All cross section values were determined relative to those of the 115In(n, n′)115mIn reaction. The activities induced by the low-energy neutrons were corrected. For the corrections, the neutron spectra and mean neutron energies at the irradiation positions were calculated taking into account the energy loss of incident deuterons, the angular differential cross section of the d-D reaction and the solid angle subtended by the sample. The systematics of the (n, p) reactions at the neutron energy of 5.0 MeV in the mass range between 27 and 92 were proposed for the first time. This systematics can predict the cross sections within an accuracy of a factor of 1.6.