Constraining properties of neutron stars with heavy-ion reactions in terrestrial laboratories

TL;DR

This paper discusses how heavy-ion reactions in laboratories can constrain the nuclear symmetry energy, which in turn informs neutron star properties and fundamental physics questions.

Contribution

It demonstrates how experimental heavy-ion data constrains the density dependence of nuclear symmetry energy, impacting neutron star models and gravitational physics.

Findings

Constraints on symmetry energy around saturation density

Implications for neutron star radii and cooling

Limits on the variation of gravitational constant G

Abstract

Heavy-ion reactions provide a unique means to investigate the equation of state (EOS) of neutron-rich nuclear matter, especially the density dependence of the nuclear symmetry energy $E_{sym}(\rho)$. The latter plays an important role in understanding many key issues in both nuclear physics and astrophysics. Recent analyses of heavy-ion reactions have already put a stringent constraint on the $E_{sym}(\rho)$ around the saturation density. This subsequently allowed us to constrain significantly the radii and cooling mechanisms of neutron stars as well as the possible changing rate of the gravitational constant G.