Sudden emission of nucleons at scission

摘要

At a certain finite neck radius during the descent of a fissioning nucleus from the saddle to the scission point, the attractive nuclear forces can no more withstand the repulsive Coulomb forces producing the neck rupture and the sudden absorption of the neck stubs by the fragments. At that moment the nucleons, although still characterized by their pre-scission wave functions, find themselves in the newly created potential of their interaction with the separated fragments. Their wave functions become wave packets with components in the continuum. The probability to populate such states gives evidently the emission probability of nucleons at scission. In this way we have studied scission neutrons and protons for the fissioning nucleus U-236, using two-dimensional realistic nuclear shapes.