# The symmetry energy of the nuclear EoS: a study of collective motion and low-energy reaction dynamics in semiclassical approaches

## TL;DR

This paper investigates how the symmetry energy component of the nuclear equation of state influences collective motion and low-energy reaction dynamics in neutron-rich systems, using semiclassical transport models.

## Contribution

It provides new insights into the sensitivity of collective excitations and pre-equilibrium phenomena to the symmetry energy below normal nuclear density.

## Key findings

- Dipole oscillations in neutron-rich systems are sensitive to the symmetry energy.
- Pre-equilibrium dipole oscillations near Coulomb barrier depend on the symmetry energy behavior.
- Nucleon emission patterns are influenced by the symmetry energy and other effective interaction terms.

## Abstract

In the framework of mean-field based transport approaches, we discuss recent results concerning collective motion and low-energy heavy ion reactions involving neutron-rich systems. We focus on aspects which are particularly sensitive to the isovector terms of the nuclear effective interaction and the corresponding symmetry energy. As far as collective excitations are concerned, we discuss the mixed nature of dipole oscillations in neutron-rich systems. On the other hand, for reactions close to the Coulomb barrier, we investigate the structure of pre-equilibrium collective dipole oscillations, focusing on their sensitivity to the symmetry energy behavior below normal density. Nucleon emission is also considered within the same context. The possible impact of other relevant terms of the nuclear effective interaction on these mechanisms is also examined. From this analysis we expect to put further constraints on the nuclear Equation of State, of crucial importance also in the astrophysical context.