Equatorial, collinear trajectories in the ternary fission of 252Cf for various third fragments

To understand the dynamics of the ternary fission process, trajectory calculations play an important role. Within the classical physics concept, the trajectories of the fragments in a spontaneous ternary fission of (252)(98) Cf are studied. Taking into account the conservation laws, the force acting between the fragments dictates the future path. A good set of parameters needed for the initial configuration can be designed from the known experimental information on the angular and energy distributions of the ternary fission fragments. Else, various initial parameters can be tuned to obtain the desired final results to match with the experimental angular and energy distribution of the fragments. Initial parameters such as the distance between the fission fragments, velocity and position of the fragments are chosen from the earlier theoretical and experimental studies. The kinetic energy and position of the fragments are calculated numerically for different ternary fission fragments. The results indicate that the final angle of the light third fragment is almost around 90 degrees, and it is independent of the initial angle having a preference for equatorial and/or orthogonal emission of third fragments with respect to the other two fission fragments. For heavier third fragments, a strong dependence on the initial angle is seen in the final emission direction, which for very low angles results in collinear type trajectories, supporting the experimental observation of collinear cluster tripartition.