From Di-Nucleus to Mono-Nucleus - Neck Evolution in Fusion of Massive Systems -

TL;DR

This paper investigates the evolution of the neck degree of freedom during heavy ion fusion, revealing rapid formation of a mono-nucleus with superdeformation and discussing the Langevin approach for modeling these dynamics.

Contribution

It introduces a detailed analysis of neck dynamics and early equilibration in heavy ion fusion, applying Langevin dynamics to superheavy element synthesis.

Findings

Neck degree of freedom equilibrates early during fusion.

Formation of a superdeformed mono-nucleus occurs rapidly.

Coupled dynamics of degrees of freedom are essential for accurate modeling.

Abstract

Dynamics of the neck degree of freedom during fusioning process between heavy ions is studied. Time scales of the three degrees of freedom (the relative distance, the neck and the mass-asymmetry) are studied, showing an early equilibration of the neck. This means that a di-nucleus formed by the incident combination of ions quickly forms a mono-nucleus with a superdeformation during the fusion process and that the other two degrees of freedom have to be solved in a coupled way. A brief introduction of Langevin approach and dissipation-fluctuation dynamics is also given and of the application to the synthesis of the superheavy elements.