Constraining the equation of state of nuclear matter from competition of fusion and quasi-fission in the reactions leading to production of the superheavy elements

TL;DR

This paper investigates fusion hindrance in superheavy element production using a transport model, deriving constraints on nuclear matter properties by comparing simulations with experimental fusion probabilities.

Contribution

It introduces a novel approach to constrain the nuclear equation of state by analyzing fusion and quasi-fission competition in superheavy element synthesis.

Findings

Constraints on the modulus of incompressibility: 240-260 MeV

Rejection of stiff symmetry energy density-dependence ($b3>1$)

First-time use of experimental fusion data to constrain nuclear matter properties

Abstract

The mechanism of fusion hindrance, an effect preventing the synthesis of superheavy elements in the reactions of cold and hot fusion, is investigated using the Boltzmann-Uehling-Uhlenbeck equation, where Coulomb interaction is introduced. A strong sensitivity is observed both to the modulus of incompressibility of symmetric nuclear matter, controlling the competition of surface tension and Coulomb repulsion, and to the stiffness of the density-dependence of symmetry energy, influencing the formation of the neck prior to scission. The experimental fusion probabilities were for the first time used to derive constraints on the nuclear equation of state. A strict constraint on the modulus of incompressibility of nuclear matter $K_0 = 240 - 260$ MeV is obtained while the stiff density-dependences of the symmetry energy ($\gamma>1.$) are rejected.