Deformation of fission fragments at scission studied by 4D Langevin model

Systematic and anomalous trends in fragment mass and TKE (total kinetic energy) distributions are investigated in terms of the 4D Langevin model developed at Tokyo Tech. We have found that correlated transitions in symmetric components and dominant modes (symmetric v.s. asymmetric) can explain the prominent systematic and anomalous features of fission observables. We have also elucidated that interplay between spherical and deformed magicity at A=132 and A=142 to 144 is important in both observables.