Microscopic Theory of Nuclear Fission

TL;DR

This paper models the nuclear fission process of plutonium-240 using advanced density functional theory, highlighting the crucial role of pairing correlations in enabling shape evolution and revealing a slower, fully non-adiabatic dynamic process.

Contribution

It introduces a comprehensive real-time, non-adiabatic DFT approach to nuclear fission that accounts for all collective degrees of freedom without symmetry restrictions.

Findings

Pairing correlations act as a lubricant in fission dynamics.

Fission evolution is slower than previously thought.

All collective degrees of freedom participate in the dynamics.

Abstract

We describe the fission dynamics of $^{240}$Pu within an implementation of the Density Functional Theory (DFT) extended to superfluid systems and real-time dynamics. We demonstrate the critical role played by the pairing correlations, which even though are not the driving force in this complex dynamics, are providing the essential lubricant, without which the nuclear shape evolution would come to a screeching halt. The evolution is found to be much slower than previously expected in this fully non-adiabatic treatment of nuclear dynamics, where there are no symmetry restrictions and all collective degrees of freedom (CDOF) are allowed to participate in the dynamics.