Measurement of neutron activation cross sections for energies up to 40 MeV for natural samples of Mg, Si, Ca, V, Cr, Cu and Zn

The cross section measurements of 17 neutron induced reactions using an intense semimonoenergetic neutron field were recently reported. Neutrons for energies up to 40 MeV were produced by a simple Be target system bombarded by protons of 9 different energies between 20 and 40 MeV. Successively in this neutron field, we measured the cross sections of 15 reactions of natMg(n, Xnp)24Na, natSi(n, Xn2p)27Mg, natSi(n, Xnp)28Al, natSi(n, Xnp)29Al, natCa(n, Xnp)42K, natCa(n, Xnp)43K, natV(n, Xn2p)46Sc, natV(n, Xn2p)47Sc, natCr(n, Xnp)52V, natCr(n, Xnp)53V, natCu(n, Xn2p)62mCo (T1/2=14 min), natZn(n, Xn2p)65Ni, natZn(n, Xnp)64Cu, natZn(n, Xnp)66Cu and natZn(n, Xnp) 68mCu (T1/2=3.8 min) by irradiating natural samples of Mg, Si, Ca, V, Cr, Cu and Zn. The excitation functions of these reactions were obtained by using the leastsquares fitting (LSF) of the cross-section values calculated with the ALICE/LIVERMORE82 code, and also by using the SAND-II and the NEUPAC unfolding codes with the initial guess values derived from the LSF results and empirical reference data. (author)