Model for particle emission from a fissioning system

The differential emission probability for a neutron emitted in a binary fission process due to nonadiabatic effects in the coupling of the single-particle degrees of freedom to the accelerated relative motion of the fragments is investigated within a model which represents each nucleus by a nondeformed one-term separable potential. Initially the neutron is bound in a two-center eigenstate, referring to a certain separation distance of the centers of the potentials. The collective relative motion is assumed to proceed with zero angular momentum along a trajectory which is calculated from classical equations of motion including conservative and phenomenological frictional forces. The derivation of measurable quantities from the asymptotic solution of the time-dependent Schroedinger equation for the single particle wave function is carefully examined. Numerical calculations have been performed for parameter values which simulate 252Cf(sf). The calculated energy spectra and angular distributions of the emitted particles are presented for different values of the mass asymmetry