Evaporation and fission of the primary fragments produced by multinucleon transfer reactions

Abstract

The multinucleon transfer (MNT) reaction has aroused wide interest in recent years largely due to its ability to produce neutron-rich heavy nuclei. The semiclassical model GRAZING can describe well the experimental MNT data for many medium-heavy systems, but only simply considers neutron evaporation in the deexcitation of primary fragments. In order to describe the final MNT products for heavy and even superheavy systems, we try to consider both the transfer and subsequent deexcitation processes by combining, for the first time, the GRAZING model and the statistical-decay model GEMINI as well as the improved version GEMINI++. Considering fission in the deexcitation of primary fragments by GEMINI++ model, the isotope distributions of final fragments are much wider than those only by GRAZING model, indicating an important role of fission in the deexcitation process for heavy and superheavy fragments. However, our results have large deviations from the GRAZING-F results, which may result from the different technique adopted in the deexcitation process. Moreover, it is shown that the GEMINI++ model is more reasonable than the GEMINI model, because the latter overpredicts the fission probability and the width of fission isotope distributions to a large extent. With GEMINI++ model, the predictions of cross sections for final isotopes can be improved by taking into account charged-particle evaporations, especially the α evaporation.