Nuclear Fission Dynamics: Past, Present, Needs, and Future

Abstract

Recent developments in theoretical modeling and in computational power have allowed us to make significant progress on a goal not achieved yet in nuclear theory: a fully microscopic theory of nuclear fission. The complete microscopic description remains a computationally demanding task, but the information that can be provided by current calculations can be extremely useful to guide and constrain phenomenological approaches. First, a truly microscopic framework that can describe the real-time dynamics of the fissioning system can justify or rule out assumptions and approximations incompatible with an accurate quantum treatment or with our understanding of the inter nucleon interactions. Second, the microscopic approach can be used to obtain trends such as: the excitation energy sharing mechanism between fission fragments (FFs) with increasing excitation energy of the fissioning system, the angular momentum content of the FFs, or even to compute observables that cannot be otherwise calculated in phenomenological approaches or even measured, as in the case of astronomical environments. Merely the characterization of the trends would be of great importance for various application. We present here arguments that a truly microscopic approach to fission does not support the assumption of adiabaticity of the large amplitude collective motion in fission, particularly starting from the outer saddle down to the scission configuration.

arXiv comment14 pages, 7 figures,, published version

References in corpus (37)

• Structure of even-even nuclei using a mapped collective Hamiltonian and the D1S Gogny interaction
• Phenomenology of Forward Hadrons in DIS: Fracture Functions and its $Q^2$ Evolution
• Microscopic Theory of Nuclear Fission: A Review
• Screening of the topological charge in a correlated instanton vacuum
• Microscopic approach of fission dynamics applied to fragment kinetic energy and mass distributions in 238U
• Induced Fission of ${}^{240}$Pu within a Real-Time Microscopic Framework
• Brownian shape motion on five-dimensional potential-energy surfaces: Nuclear fission-fragment mass distributions
• Review on the progress in nuclear fission
• Formation and dynamics of fission fragments
• Fission fragment charge and mass distributions in 239Pu(n,f) in the adiabatic nuclear energy density functional theory
• Fission-fragment mass distributions from strongly damped shape evolution
• Entropy-driven excitation-energy sorting in superfluid fission dynamics
• Fission Dynamics of 240Pu from Saddle-to-Scission and Beyond
• Fission dynamics within time-dependent Hartree-Fock: deformation-induced fission
• Calculation of fission observables through event-by-event simulation
• Microscopic modeling of mass and charge distributions in the spontaneous fission of 240Pu
• A 4-dimensional Langevin approach to low-energy nuclear fission of ${}^{236}$U
• Time-Dependent Density Functional Theory and the Real-Time Dynamics of Fermi Superfluids
• Systematics of the first 2+ excitation with the Gogny interaction
• Nuclear Fission Dynamics: Past, Present, Needs, and Future
• From Asymmetric to Symmetric Fission in the Fermium Isotopes within the Time-Dependent GCM Formalism
• Correlated Prompt Fission Data in Transport Simulations
• Final excitation energy of fission fragments
• Fission dynamics within time-dependent Hartree-Fock: boost-induced fission
• Collective aspects deduced from time-dependent microscopic mean-field with pairing: application to the fission process
• Formation and distribution of fragments in the spontaneous fission of 240Pu
• Unitary evolution with fluctuations and dissipation
• Fission dynamics of ${}^{252}$Cf
• Time-Dependent Density Functional Theory for Fermionic Superfluids: from Cold Atomic Gases, to Nuclei and Neutron Stars Crust
• Numerical accuracy of mean-field calculations in coordinate space
• Angular momentum of fission fragments
• Coordinate-Space Solver for Superfluid Many-Fermion Systems with Shifted Conjugate Orthogonal Conjugate Gradient Method
• Projection of Good Quantum Numbers for Reaction Fragments
• Scission Dynamics with K Partitions
• Structures in the energy distribution of the scission neutrons: finite neutron-number effect
• Determining the average prompt-fission-neutron multiplicity for ${}^{239}$Pu($n$,$f$) via a ${}^{240}$Pu($\alpha$,${\alpha }^{\prime }f$) surrogate reaction
• Nuclear Fission: from more phenomenology and adjusted parameters to more fundamental theory and increased predictive power

Cited by in corpus (40)

• Future of Nuclear Fission Theory
• Theory of Nuclear Fission
• Nuclear Fission Dynamics: Past, Present, Needs, and Future
• Dynamical synthesis of 4He in the scission phase of nuclear fission
• Fission fragments intrinsic spins and their correlations
• Nucleosynthesis and observation of the heaviest elements
• Measures of complexity and entanglement in fermionic many-body systems
• Extension of the Hauser-Feshbach Fission Fragment Decay Model to Multi-Chance Fission
• Microscopic analysis of induced nuclear fission dynamics
• Entanglement entropy, single-particle occupation probabilities, and short-range correlations
• Time-dependent generator coordinate method study of fission: dissipation effects
• Generalized time-dependent generator coordinate method for induced fission dynamics
• Fission dynamics, dissipation and clustering at finite temperature
• Neck Rupture and Scission Neutrons in Nuclear Fission
• The angular correlation between the fission fragment intrinsic spins
• Generalized time-dependent generator coordinate method for small and large amplitude collective motion
• Spatial orientation of the fission fragment intrinsic spins and their correlations
• Pairing dynamics and solitonic excitations in collisions of medium-mass, identical nuclei
• Pure quantum extension of the semiclassical Boltzmann-Uehling-Uhlenbeck equation
• Fission Fragment Excitation Energy Sharing Beyond Scission
• Smoothing of one- and two-dimensional discontinuities in potential energy surfaces
• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• Connection of four-dimensional Langevin model and Hauser-Feshbach theory to describe statistical decay of fission fragments
• Sensitivity to the initial conditions of the Time-Dependent Density Functional Theory
• New developments in fission studies within the time-dependent density functional theory framework
• Pre-equilibrium Neutron Emission in Fission or Fragmentation
• Time-dependent density functional theory study of induced-fission dynamics of ${}^{226}$Th
• Non-Markovian character and irreversibility of real-time quantum many-body dynamics
• Time-Dependent Density Functional Theory Description of ${}^{238}$U(n,f), ${}^{240,242}$Pu(n,f) and ${}^{237}$Np(n,f) Reactions
• Inertial energy dissipation in nuclear dynamics
• Examining the justification for the introduction of a fermion localization function
• Pair production as a probe for the dynamics of nuclear fission and $\alpha$ decay
• Fragment Intrinsic Spins and Fragments' Relative Orbital Angular Momentum in Nuclear Fission
• A critical assessment of the current implementations of the Generator Coordinate Method
• Framework for Polarized Superfluid Fermion Systems
• A Nonequilibrium Information Entropy Approach to Ternary Fission of Actinides
• Shell effects in quasifission toward ${}^{180}\mathrm{Hg}$: insights into fission asymmetric modes
• Microscopic Theory of Nuclear Fission
• Isotopic fission yields of ${}^{240}$Pu as a function of the excitation energy
• The LISE package: solvers for static and time-dependent superfluid local density approximation equations in three dimensions