Quantal Diffusion Description of Multi-Nucleon Transfers in Heavy-Ion Collisions

TL;DR

This paper introduces a quantal diffusion model based on the stochastic mean-field approach to accurately describe multi-nucleon transfer in heavy-ion collisions, incorporating shell effects without adjustable parameters.

Contribution

The authors develop a parameter-free quantal diffusion framework using the stochastic mean-field approach, integrating shell effects and satisfying fluctuation-dissipation relations for heavy-ion collision analysis.

Findings

Accurately predicts fragment mass distributions in heavy-ion collisions.

Incorporates shell effects into the diffusion description.

Shows good agreement with experimental data for $^{48}$Ca+$^{238}$U.

Abstract

Employing the stochastic mean-field (SMF) approach, we develop a quantal diffusion description of the multi-nucleon transfer in heavy-ion collisions at finite impact parameters. The quantal transport coefficients are determined by the occupied single-particle wave functions of the time-dependent Hartree-Fock equations. As a result, the primary fragment mass and charge distribution functions are determined entirely in terms of the mean-field properties. This powerful description does not involve any adjustable parameter, includes the effects of shell structure and is consistent with the fluctuation-dissipation theorem of the non-equilibrium statistical mechanics. As a first application of the approach, we analyze the fragment mass distribution in $^{48}\mathrm{Ca}+{}^{238}\mathrm{U}$ collisions at the bombarding energy $E_{\text{c.m.}}=193$ MeV and compare the calculations with the experimental data.