Non-Equilibrium Aspects of Fission Dynamics within the Time Dependent Density Functional Theory

In the first microscopic description of induced fission, based on a full implementation of the Time-Dependent Density Functional Theory (TDDFT) extended to superfluid fermion system, using only 8 well known parameters (energy and density of symmetric nuclear matter, nuclear surface tension, symmetry energy and its density dependence, strength of the spin-orbit and pairing interactions, and proton charge), without any fitting or unchecked assumptions, and with controlled approximations, it was demonstrated that the fission dynamics from saddle-to-scission has a strongly non-equilibrium character. This is the apparent behavior of a viscous fluid and the use of the widely used adiabatic hypothesis is invalid. Within this theoretical framework the need for a collective potential energy surface and for a collective inertia become both superfluous and irrelevant and the role of the pairing correlations is crucial. A very good agreement was obtained with the experimental data for total kinetic energy of the fission fragments, their average masses, charges, excitation energies, intrinsic fission fragment angular momenta and their correlations. The dependence of these properties with excitation energy of the formed compound nucleus was studied and general features observed in experiments were also observed.