No abstract

With the quantum diffusion approach, the passing probability through the parabolic barrier is examined in the limit of linear coupling in the momentum between the collective subsystem and environment. The dependencies of the penetrability on time, energy, and the coupling strength between the interacting subsystems are studied. The quasistationary thermal decay rate from a metastable state is considered in the cases of linear couplings both in the momentum and in the coordinate.

The capture of a projectile nucleus by a target nucleus at bombarding energies below the Coulomb barrier is studied on the basis of the quantum diffusion approach. The results obtained in this way for reactions involving spherical nuclei are in good agreement with available experimental data. It is shown that, beyond the range of nuclear forces, the decrease in the capture cross section as the bombarding energy decreases becomes slower.