Aurel Bulgac (U. Washington)
Unraveling The Many Facets of Non-Equilibrium Fission Dynamics: A Real-Time Quantum Approach

When comparing nuclear fission at the venerable age of almost 84 years old with other quantum many-body systems (superconductivity, superfluidity, quantum Hall effect, fractional quantum Hall effect, magnetism, etc.) it is surprising to find out how little is known and microscopically justified for this complex quantum non-equilibrium process. In the last decade a significant advancenment was achieved in modeling and disentangling aspects of fission, by means of a pure quantum approach. The level of agreement with observations, without the resort to any unverified theoretical assumptions, uncontrolled numerical approximations, or phenomenology and incorporating only the basic input needed to reproduce most of the well-known properties of nuclei, is surprisingly good. The theoretical framework requires only eight input parameters at most: the nuclear saturation density and energy, surface tension, the symmetry energy and its density dependence to a lesser degree, proton charge, the spin-orbit and the nuclear pairing interaction strengths. Some of our foremost theoretical findings are: i) the strongly- damped character of the large amplitude collective motion beyond the outer saddle-point, ii) the fission fragment excitation energies and its sharing mechanism, and the somewhat surprising excitation energy exchange mechanism between the fission fragments before the fission fragments are fully accelerated, iii) the intrinsic fission fragment spins and their unexpected correlation character, iv) the nature and the properties of the non-equilibrium neutrons emitted before the fission fragments are fully accelerated, v) the strongly damped character of the fission fragment shape evolution after they are spatially separated, vi) the total kinetic energy of the fission fragments, vii) and the evolution of these properties with the initial excitation energy of the compound nucleus.