Fission Dynamics of Compound Nuclei: Pairing versus Fluctuations

Abstract

Energy dependence of fission observables is a key issue for wide nuclear applications. We studied real-time fission dynamics from low-energy to high excitations in the compound nucleus ${}^{240}$Pu with the time-dependent Hartree-Fock+BCS approach. It is shown that the evolution time of the later phase of fission towards scission is considerably lengthened at finite temperature. As the role of dynamical pairing is vanishing at high excitations, the random transition between single-particle levels around the Fermi surface to mimic thermal fluctuations is indispensable to drive fission. The obtained fission yields and total kinetic energies with fluctuations can be divided into two asymmetric scission channels, namely S1 and S2, which explain well experimental results, and give microscopic support to the Brosa model. With increasing fluctuations, S2 channel takes over S1 channel and the spreading fission observables are obtained.

5 pages, 4 figures

References in corpus (5)

• A Stochastic Mean-Field Approach For Nuclear Dynamics
• Fission Barriers of Compound Superheavy Nuclei
• Timescales of quantum equilibration, dissipation and fluctuation in nuclear collisions
• Pairing interactions and the vanishing pairing correlations in hot nuclei
• Superfluid dynamics of 258Fm fission

Cited by in corpus (12)

• Bayesian evaluation of charge yields of fission fragments of 239U
• Microscopic analysis of induced nuclear fission dynamics
• Optimizing multilayer Bayesian neural networks for evaluation of fission yields
• Energy and pairing dependence of dissipation in real-time fission dynamics
• Fission dynamics, dissipation and clustering at finite temperature
• Microscopic description of the torque acting on fission fragments
• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• Modeling survival probabilities of superheavy nuclei at high excitations
• Correlations between nuclear landscape boundaries and neutron-rich r-process abundances
• Time-dependent density functional theory study of induced-fission dynamics of ${}^{226}$Th
• Postfission properties of uranium isotopes: A hybrid method with Langevin dynamics and the Hauser-Feshbach statistical model
• Microscopic self-consistent description of induced fission: dynamical pairing degree of freedom