Multidimensional Langevin approach to description of near-barrier heavy-ion fusion and deep-inelastic collisions

Abstract

A six-dimensional Langevin approach is developed for the analysis of near-barrier heavy- ion fusion and deep-inelastic collisions. In its framework, vibrational and rotational degrees of freedom of both nuclei are taken into account explicitly. Calculated fusion cross sections, compound nuclei spin distributions, and angular and energy distributions of deep-inelastic products showsatisfactory agreement with experimental data. c � 2003 MAIK "Nauka/Interperiodica". Fokker-Planck and Langevin equations may be successfully applied for the description of low-energy fusion and deep-inelastic collisions. These equations are based on the concepts of nuclear friction and stochastic behavior of the system with many degrees of freedom. The solution of the Langevin equations is less difficult compared to the Fokker-Planck equa- tion and does not require additional simplifying as- sumptions. It is well known that the deformations of nuclear surfaces and the rotation of deformed nuclei seriously affect the dynamics of nuclear interaction. Therefore, taking them into account is important for the description of low-energy nucleus-nucleus colli- sions. But this dramatically increases the calculation time and difficulty, which is the main reason why up to nowonly tw o- or four-dimensional calculations have been performed (1). In the present work, vibra- tional and rotational degrees of freedom of both nuclei are taken into account explicitly in the framework of the six-dimensional Langevin approach. Fusion cross sections, compound nuclei spin distributions, and angular and energy distributions of deep-inelastic products are calculated and compared with experi- mental data.