NUCLEAR-DATA RELEVANT TO THE PRODUCTION OF I-120G VIA THE TE-120(P,N)-PROCESS AT A SMALL-SIZED CYCLOTRON

Excitation functions of the nuclear reactions Te-120(p,xn)I-119,I-120m .g were measured for the first time from their respective thresholds u p to 35 MeV. Use was made of the stacked-foil technique. Thin samples were prepared by electrolytic deposition of highly enriched Te-120 (99 .0%) on Ti-backing. Integral yields of I-119,I-120m.g were calculated from the measured cross section data. For the production of the medica lly interesting beta(+)-emitting radioisotope I-120g (T-1/2 = 1.35 h) the energy range E-p = 16 --> 9 MeV appears to be optimum, the thick t arget yield of I-120g amounting to 2.3 GBq (62 mCi)/mu Ah and the I-12 0m and I-119 impurity levels to 4.8 and 4.4%. respectively. A comparis on of the Te-122(p,3n)- and Te-120(p,n)-processes for the production o f I-120g is given. Despite the higher cost of the target material, the Te-120(p,n)-process is superior since a small-sized cyclotron is adeq uate and the radionuclidic quality of the product is better. (C) 1998 Elsevier Science Ltd. All rights reserved.