Hybrid model analysis of the excitation function for alpha induced reaction on 121Sb and 123Sb

Excitation functions for the reactions 121Sb(α,xn)sup(125-x)I, 123Sb(α,xn)sup(127-x)I and 121Sb(α,p3n)121Te were obtained from the measurements of the residual activity of stacked foils of antimony trioxide evaporated on Al backings from threshold to 60 MeV. The excitation functions for the production of 121I, 123I, 124I, 126I and 121Te are presented. The experimental data are compared with calculations considering equilibrium as well as pre-equilibrium reaction mechanism according to the hybrid model of Blann. The high energy part of the excitation functions are dominated by the pre-equilibrium reaction mechanism. Calculations were done using a priori calculational method of Overlaid Alice Code of Blann. Most of the excitation functions in the energy range mentioned above could very well be fitted with the hybrid model calculation for exciton number n=4 with nsub(n)=2 and nsub(p)=2. The overall agreement with the theory is good. Certain discrepancies for example 121Sb(α,p3n)121Te excitation function, indicate that the production mechanism is different from the one presumed for the calculation. (author). 4 tabs., 7 figs., 23 refs