Correlations between isospin dynamics and Intermediate Mass Fragments emission time scales: a probe for the symmetry energy in asymmetric nuclear matter

TL;DR

This study investigates how isospin dynamics and intermediate mass fragment emission timescales relate to the symmetry energy in asymmetric nuclear matter, using experimental data and theoretical models to provide new constraints.

Contribution

It introduces a combined experimental and theoretical approach to constrain the density dependence of symmetry energy through fragment emission analysis.

Findings

Evidence for a moderately stiff symmetry energy potential term.

Discrimination between statistical and dynamical fragment emission.

Constraints on the density dependence of symmetry energy.

Abstract

We show new data from the $^{64}$Ni+$^{124}$Sn and $^{58}$Ni+$^{112}$Sn reactions studied in direct kinematics with the CHIMERA detector at INFN-LNS and compared with the reverse kinematics reactions at the same incident beam energy (35 A MeV). Analyzing the data with the method of relative velocity correlations, fragments coming from statistical decay of an excited projectile-like (PLF) or target-like (TLF) fragments are discriminated from the ones coming from dynamical emission in the early stages of the reaction. By comparing data of the reverse kinematics experiment with a stochastic mean field (SMF) + GEMINI calculations our results show that observables from neck fragmentation mechanism add valuable constraints on the density dependence of symmetry energy. An indication is found for a moderately stiff symmetry energy potential term of EOS.