Compound nucleus formation probabilityP_CNdefined within the dynamical cluster-decay model

Abstract

Abstract. With in the dynamical cluster-decay model (DCM), the compound nucleus fusion/ formation probability P CN is defined for the first time, and its variation with CN excitation energy E * and fissility parameter χ is studied. In DCM, the (total) fusion cross section σ f usion is sum of the compound nucleus (CN) and noncompound nucleus (nCN) decay processes, each calculated as the dynamical fragmentation process. The CN cross section σ CN is constituted of the evaporation residues (ER) and fusion-fission (ff), including the intermediate mass fragments (IMFs), each calculated for all contributing decay fragments (A 1 , A 2 ) in terms of their formation and barrier penetration probabilities P 0 and P. The nCN cross section σ nCN is determined as the quasi-fission (qf) process where P 0 =1 and P is calculated for the entrance channel nuclei. The calculations are presented for six different target-projectile combinations of CN mass A∼100 to superheavy, at various different center-of-mass energies with effects of deformations and orientations of nuclei included in it. Interesting results are that the P CN =1 for complete fusion, but P CN <1 or <<1 due to the nCN conribution, depending strongly on both E * and χ.