Rotation of Scissioning Nuclei Observed in Ternary Fission Induced by Polarized Neutrons

摘要

Angular distributions of light charged particles relative to the momentum of the light fission fragment were studied in ternary fission induced by cold polarized neutrons. It was dis-covered that the angular distribution is asymmetric with respect to a plane determined by the di-rection of incident neutron spin and the light fragment momentum. The violation of the mirror-like symmetry was established at the level of ~10~(-2) - 10~(-4) for three reactions studied: ~(233)U(n,f), ~(235)U(n,f) and ~(239)Pu(n,f). In spite of the smallness of the effects the neutron spin flip method allowed to make reliable measurements. The current status of the experimental studies of the effect and its interpretation are presented. Perspectives for further studies of the new phenomenon are discussed.