Microscopic description of the torque acting on fission fragments

Abstract

When two fragments are created in a fission decay, any torque due to nuclear and Coulomb interaction can change the fragment's angular momentum. This article explores the character and magnitude of the angular momentum as a function of the initial conditions around the scission point using the time-dependent Hartree-Fock theory. To understand the torque acting on the fragments, the Frozen Hartree-Fock method is also used to determine the collective potential at scission. Two ${}^{240}$Pu fission channel ( ${}^{132}$Sn+${}^{108}$Ru and ${}^{144}$Ba+${}^{96}$Sr ) are studied. These two channels cover different shapes (spherical, quadrupole, and octupole deformation) of the fragments. It is found that the angular momentum generated by the Coulomb interaction after fission is mainly collective, while this is not the case for the angular momentum generated at scission. The competition between rotational modes (bending, wriggling, and twisting) is discussed and shows that the angular momentum is generated mainly perpendicular to the fission axis.

8 pages, 10 figures

References in corpus (10)

• Energy dependence of nucleus-nucleus potential close to the Coulomb barrier
• How the Pauli exclusion principle affects fusion of atomic nuclei
• Generation of fragment angular momentum in fission
• Dynamical synthesis of 4He in the scission phase of nuclear fission
• Nucleon localization and fragment formation in nuclear fission
• Fission fragments intrinsic spins and their correlations
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• Time-Depentent Hartree-Fock description of heavy ions fusion
• Pauli energy contribution to nucleus-nucleus interaction
• The angular correlation between the fission fragment intrinsic spins

Cited by in corpus (9)

• Spatial orientation of the fission fragment intrinsic spins and their correlations
• Generation, dynamics, and correlations of the fission fragments' angular momenta
• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• New developments in fission studies within the time-dependent density functional theory framework
• Microscopic Study of Spin Transfer in Near-Barrier Nuclear Reactions
• Meaurement of spin vs. TKE of ${}^{144}$Ba produced in spontaneous fission of ${}^{252}$Cf
• Quantum-mechanical description of angular motion of fission fragments at scission
• Microscopic theory of angular momentum distributions across the full range of fission fragments
• Two-center harmonic oscillator basis for Skyrme-DFT calculations (I): formalism and Proof of Principle