NEAR-SCISSION ALPHA-PARTICLES IN FUSION-FISSION REACTION

There is strong experimental evidence that low energy fusion-fission r eactions are accompanied by an emission of alpha particles whose chara cteristics cannot be explained by statistical pre-scission emission fr om the compound system nor by post-scission emission from the accelera ted fission fragments. These particles are found at angles close to 90 degrees (with respect to the fission axis). They seem to originate fr om the neck area of the system and be emitted near scission. We discus s possible mechanisms responsible for their emission and present a dyn amical study of their motion in the Coulomb and nuclear fields of the separating fission fragments.