Excitation functions of Te-124(d,xn)I-124,I-125 reactions from threshold up to 14 MeV: comparative evaluation of nuclear routes for the production ofI-124

Excitation functions of the nuclear reactions Te-124(d,xn)I-124,I-125 were measured from their respective thresholds up to 14.0 MeV via the stacked-fo il technique. Thin samples were prepared by electrolytic deposition of 99.8 % enriched 124 Te on Ti-backing. The excitation function of the Te-124(d,n) I-125 reaction was measured for the first time. The present data for the Te -124(d,2n)I-124 reaction are by an order of magnitude higher than the liter ature experimental data but are in good agreement with the results of a hyb rid model calculation. From the measured cross sections, integral yields of I-124,I-125 were calculated, The energy range E-d= 14 --> 10 MeV appears t o be the best compromise between I-124- yield and I-125-impurity. The calcu lated I-124-yield amounts to 17.5 MBq/muA h and the I-125-impurity to 1.7%. A critical evaluation of the three nuclear routes for the production of I- 124, viz Te-124(d,2n)-, Te-124(p,n)- and Te-125(p,2n)-processes, is given. The reaction studied in this work proved to be least suitable. The Te-124(p ,n)-reaction gives I-124 of the highest radionuclidic purity, and a small-s ized cyclotron is adequate for production purposes. The Te-125(p,2n)-reacti on is more suitable at a medium-sized cyclotron: the yield of I-124 is four times higher than in the other two reactions but the level of 0.9% I-125-i mpurity is relatively high. (C) 2001 Elsevier Science Ltd. All rights reser ved.