Fission Fragment Formation and Fission Yields in Nucleon-induced Reactions up to 1 GeV

The fission fragment formation is considered as the neck instability in the process of octupole oscillations of neutrons and protons near the scission point. To describe such a phenomenon the potential surface of fissionning nucleus with neck radius about 1 fin was calculated with shell correction approach. The new version of smooth part of the deformation energy is proposed. The liquid drop part is formulated in a double folding model with n-n, p-p, and n-p Yukawa interaction potential. Fission fragment mass and charge distributions correspond to isoscalar and isovector modes of vibrations and are defined by wave functions of oscillations. The preliminary calculation results have shown a rather good description of main fission yield observables in a wide energy region of neutron and proton beam.