Spatial orientation of the fission fragment intrinsic spins and their correlations

Abstract

New experimental and theoretical results obtained in 2021 made it acutely clear that more than 80 years after the discovery of nuclear fission we do not understand the generation and dynamics of fission fragment (FF) intrinsic spins well, in particular their magnitudes, their spatial orientation, and their correlations. The magnitude and orientation of the primary FFs have a crucial role in defining the angular distribution and correlation between the emitted prompt neutrons, and subsequent emission of statistical (predominantly E1) and stretched E2 γ-rays, and their correlations with the final fission fragments. Here we present detailed microscopic evaluations of the FF intrinsic spins, for both even- and odd-mass FFs, and of their spatial correlations. These point to a well-defined 3D FF intrinsic spin dynamics, characteristics absent in semi-phenomenological studies, due to the presence of the twisting spin modes, which artificially were suppressed in semi-phenomenological studies.

4 pages, 3 figures

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Cited by in corpus (7)

• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• Microscopic Study of Spin Transfer in Near-Barrier Nuclear Reactions
• 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
• Quantum-mechanical description of angular motion of fission fragments at scission
• Microscopic theory of angular momentum distributions across the full range of fission fragments
• A critical assessment of the current implementations of the Generator Coordinate Method