Excitation functions of proton induced reactions on 68Zn from threshold up to 71 MeV, with specific reference to the production of 67Cu

The excitation function of the 68Zn(p, 2p)67Cu reaction was measured radiochemically up to a proton energy of 71 MeV to obtain accurate data for production of the therapy related β--emitting radioisotope 67Cu (T1/2 = 61.9 h). Investigations were also made on the (p, 2n) and (p, 3n) reactions on 68Zn. The experimental cross sections of the 68Zn(p, 2p)67Cu, 68Zn(p, 2n)67Ga and 68Zn(p, 3n)66Ga reactions were compared with published data and with theoretical predictions based on the hybrid-precompound model ALICEIPPE. Thick target yields of 67Cu, 67Ga (T1/2 = 78.3 y) and 66Ga (T1/2 = 9.4 h) were calculated. Production of 67Cu is feasible only at proton energies above 50 MeV. For the target thickness Ep = 70 → 50 MeV, the yield of 67Cu amounts to 16.9 MBq/μA.h. (orig.)