Nuclear Equation of State from ground and collective excited state properties of nuclei

TL;DR

This paper reviews current constraints on the nuclear equation of state derived from nuclear structure calculations, emphasizing the role of energy density functionals and ab initio approaches in understanding nuclear and astrophysical phenomena.

Contribution

It compares self-consistent mean-field and ab initio methods for constraining the nuclear EoS, highlighting the need to bridge these frameworks for improved understanding.

Findings

Isospin dependence of the nuclear EoS remains uncertain.

Nuclear matter incompressibility is not precisely determined.

Experimental efforts are crucial for constraining EoS properties.

Abstract

This contribution reviews the present status on the available constraints to the nuclear equation of state (EoS) around saturation density from nuclear structure calculations on ground and collective excited state properties of atomic nuclei. It concentrates on predictions based on self-consistent mean-field calculations, which can be considered as an approximate realization of an exact energy density functional (EDF). EDFs are derived from effective interactions commonly fitted to nuclear masses, charge radii and, in many cases, also to pseudo-data such as nuclear matter properties. Although in a model dependent way, EDFs constitute nowadays a unique tool to reliably and consistently access bulk ground state and collective excited state properties of atomic nuclei along the nuclear chart as well as the EoS. For comparison, some emphasis is also given to the results obtained with the so called {\it ab initio} approaches that aim at describing the nuclear EoS based on interactions fitted to few-body data only. Bridging the existent gap between these two frameworks will be essential since it may allow to improve our understanding on the diverse phenomenology observed in nuclei. Examples on observations from astrophysical objects and processes sensitive to the nuclear EoS are also briefly discussed. As the main conclusion, the isospin dependence of the nuclear EoS around saturation density and, to a lesser extent, the nuclear matter incompressibility remain to be accurately determined. Experimental and theoretical efforts in finding and measuring observables specially sensitive to the EoS properties are of paramount importance, not only for low-energy nuclear physics but also for nuclear astrophysics applications.