Decay of 118,122Ba* compound nuclei formed in 78,82Kr+40Ca reactions using the dynamical cluster-decay model of preformed clusters

Application of the preformed clusters based dynamical cluster-decay model (DCM) is made to the recent data on decay of the compound systems Ba-118,Ba-122* at a relatively low bombarding energy of 5.5 MeV/A. The same model has been applied earlier to the intermediate mass fragment (IMF) data of Ba-116*, observed at medium and higher incident energies. For the heavier Ba-118,Ba-122* systems, however, a complete mass fragmentation spectrum is observed experimentally. Except for a small narrow region of heavier mass fragments (8 <= Z(L) <= 15), the DCM gives an overall reasonable description of the observed data on both the intermediate mass fragments and the fusion-fission cross-sections, whereas the statistical model calculations based on BUSCO and GEMINI codes describe the intermediate mass fragment data and the heavier mass fragment and fusion-fission data, respectively. Within the DCM ( with preformation factor P-0 = 1), the possibility of non-compound-nucleus decay contributing to the region 8 <= Z(L) <= 15 of heavier mass fragments is also explored. All three models use the maximum angular momentum l(max) as a fitting parameter, which in the DCM is fixed via a neck-length parameter for the penetrability P -> 1.