A new approach to barrier-top fission dynamics

Abstract

We proposed a calculational framework for describing induced fission that avoids the Bohr-Wheeler assumption of well-defined fission channels. The building blocks of our approach are configurations that form a discrete, orthogonal basis and can be characterized by both energy and shape. The dynamics is to be determined by interaction matrix elements between the states rather than by a Hill-Wheeler construction of a collective coordinate. Within our approach, several simple limits can be seen: diffusion; quantized conductance; and ordinary decay through channels. The specific proposal for the discrete basis is to use the $K^{\pi }$ quantum numbers of the axially symmetric Hartree-Fock approximation to generate the configurations. Fission paths would be determined by hopping from configuration to configuration via the residual interaction. We show as an example the configurations needed to describe a fictitious fission decay ${}^{32}\mathrm{S}{\to }^{16}\mathrm{O}{+}^{16}\mathrm{O}$. We also examine the geometry of the path for fission of ${}^{236}$U, measuring distances by the number of jumps needed to go to a new $K^{\pi }$ partition.

Write-up of a talk given at the Workshop "Compound-nuclear reactions 2015" Tokyo, Oct. 19-23, 2015; 11 pages and 11 figures. To be published in European Journal of Physics, Web of Conferences

References in corpus (4)

• Brownian shape motion on five-dimensional potential-energy surfaces: Nuclear fission-fragment mass distributions
• Microscopic description of fission in Uranium isotopes with the Gogny energy density functional
• Heavy deformed nuclei in the shell model Monte Carlo method
• Nuclear fission as resonance-mediated conductance

Cited by in corpus (2)

• Composite-particle decay widths by the generator coordinate method
• Least action and the maximum-coupling approximations in the theory of spontaneous fission