EXCITATION-FUNCTIONS OF (P, 2N) AND (P, PN) REACTIONS AND DIFFERENTIAL AND INTEGRAL YIELDS OF I-123 IN PROTON-INDUCED NUCLEAR-REACTIONS ON HIGHLY ENRICHED XE-124

Excitation functions were measured for (p, 2n) and (p, pn) reactions on 99.9% enriched 124Xe from threshold up to 44 MeV. The (p, 2n) reaction is much stronger than the (p, pn) channel; above 36 MeV, however, the two processes have almost equal cross sections. Differential yields of I-123 were measured experimentally as a function of proton energy and were also calculated from the excitation functions. Our experimental and theoretical yield data are consistent within 15%, but are lower by a factor of 2 than the literature experimental values. Our studies show that the optimum energy range for the production of I-123 is E(p) = 29 --> 23 MeV. The theoretically expected thick target yield of I-123 at 6.6 h after EOB is 11.2 mCi/mu-Ah, and is in agreement with the high-current experimental production yields.