Mass distributions in a variational model

TL;DR

This paper introduces a variational approach based on the Balian-Veneroni principle to improve the description of two-body observables in nuclear physics, extending the time-dependent Hartree-Fock method.

Contribution

It proposes a modified variational method that better captures two-body observables while maintaining the Slater Determinant framework, applied to nuclear mass distributions.

Findings

Successfully applied to mass distributions in S-32 after giant dipole resonance de-excitation.

Demonstrated potential for improved collision modeling in nuclear physics.

Provides a practical implementation using the Skyrme interaction.

Abstract

The time-dependent Hartree-Fock approach may be derived from a variational principle and a Slater Determinant wavefunction Ansatz. It gives a good description of nuclear processes in which one-body collisions dominate and has been applied with success to giant resonances and collisions around the barrier. It is inherently unable to give a good description of two-body observables. A variational principle, due to Balian and Veneroni has been proposed which can be geared to good reproduction of two-body observables. Keeping the Slater Determinant Ansatz, and restricting the two-body observables to be the squares of one-body observables, the procedure can be implemented as a modification of the time-dependent Hartree-Fock procedure. Applications, using the Skyrme effective interaction, are presented for the mass distributions of fragments following de-excitation of the giant dipole resonance in S-32. An illustration of the method's use in collisions is given.