Excitation functions of 124Te(d,xn)124,125I reactions from threshold up to 14 MeV: comparative evaluation of nuclear routes for the production of 124I.
Excitation functions of the nuclear reactions 124Te(d,xn)124-125I were measured from their respective thresholds up to 14.0 MeV via the stacked-foil technique. Thin samples were prepared by electrolytic deposition of 99.8% enriched 124Te on Ti-backing. The excitation function of the 124Te(d,n)125I reaction was measured for the first time. The present data for the 124Te(d,2n)124I reaction are by an order of magnitude higher than the literature experimental data but are in good agreement with the results of a hybrid model calculation. From the measured cross sections, integral yields of 124,125I were calculated. The energy range Ed = 14 --> 10 MeV appears to be the best compromise between 124I-yield and 1251-impurity. The calculated 124I-yield amounts to 17.5 MBq/microA h and the 125I-impurity to 1.7%. A critical evaluation of the three nuclear routes for the production of 124I, viz. 124Te(d,2n)-, 124Te(p,n)- and 125Te(p,2n)-processes, is given. The reaction studied in this work proved to be least suitable. The 124Te(p,n)-reaction gives 124I of the highest radionuclidic purity, and a small-sized cyclotron is adequate for production purposes. The 125Te(p,2n)-reaction is more suitable at a medium-sized cyclotron: the yield of 124I is four times higher than in the other two reactions but the level of 0.9% 125I-impurity is relatively high.
Thick tellurium electrodeposition on nickel-coated copper substrate for 124I production.
Tellurium electrodeposition on a nickel-coated copper substrate was investigated for production of iodine-124. The electrodeposition experiments were carried out by the alkali plating baths. The optimum conditions of the electrodeposition of tellurium were as follows: 6 g l(-1) tellurium, pH=10, DC current density of ca. 8.55 mA cm(-2) and room temperature.
Compound-statistical features of deuteron-induced reactions: (II). The compound nucleus and stripping-evaporation mechanisms in (d, 2n) reactions
Abstract Six excitation functions for (d, 2n) reactions on 65Cu, 126Te, 128Te, 130Te, 133Cs and 186W have been measured radiochemically between ≈ 4 and 15 MeV. The excitation functions exhibit sharp rises above threshold and peak near the (d, 3n) thresholds at values approaching the cross sections for compound nucleus formation. The present results are included with previous data in a theoretical analysis covering the mass region above A = 47. Calculations of the excitation functions have been performed for two different mechanisms; compound nucleus formation followed by the evaporation of two neutrons and (d, n) stripping followed by the evaporation of one neutron. The compound-statistical model generally accounts very well for both the magnitudes and the energy dependences of the cross sections. The predictions of the stripping-evaporation mechanism are 15–30% of the observed cross sections. It is concluded that the compound nuclear mechanism predominates in (d, 2n) reactions above A = 47.