Measurement of quasielastic and transfer excitation functions in O-16, F-19+Th-232 reactions

Abstract

Quasielastic (QE) and transfer excitation function measurements have been carried out for the O-16, F-19 + Th-232 systems at theta(lab) = 170 degrees over a wide energy range above and below the Coulomb barrier. The data were analyzed to obtain the representation of fusion barrier distributions as well as the mean square compound nuclear spin values ([l(2)]), which are found to compare well with the results of the standard fusion model (CCDEF) calculations. Further, the back-angle transfer cross-section data as a function of the bombarding energy were transformed to give the transfer probabilities as a function of the distance of closest approach for 1p, 2p, 1 alpha, and 1p1 alpha transfer channels. The experimental "slope parameters" derived from these data were compared with the predictions of the semiclassical model calculations. It is found that the results for single nucleon or single cluster transfers are well explained by the semiclassical model, whereas for multinucleon or cluster transfers, the calculations underpredict the transfer probabilities.