Photofission of nuclei with allowance for wriggling vibrations of fissioning nuclei

Abstract

It is confirmed that one source of the large relative orbital momenta L of fragments in spontaneous and stimulated low-energy nuclear fission is quantum transverse zero-point wriggling vibrations of the fissioning system near its scission point. The angular distributions of fragments of low-energy photofission of actinide nuclei, calculated using the quantum theory of fission, are compared. Vibrations are allowed for by using parameter C w determined by Nix and Swiatecki. Agreement between the experimental and theoretical angular distributions for 234U, 236U, 238U, 238Pu, 240Pu, 242Pu nuclei is observed. The strong sensitivity of the theoretical angular distributions for 238Pu, 240Pu, 242Pu nuclei toward the choice of parameters of transient fissioning states at the external and internal fission barriers is demonstrated.