Multi-physics constraints at different densities to probe nuclear symmetry energy in hyperonic neutron stars

TL;DR

This paper investigates how hyperons influence neutron star properties by applying multi-physics constraints across different densities, revealing tensions between astrophysical observations and heavy-ion collision data within the hyperonic star models.

Contribution

It introduces a comprehensive analysis of hyperonic neutron stars using multi-physics constraints, highlighting the impact of hyperons on the parameter space and observable properties.

Findings

Hyperons affect neutron star structure and gravitational wave signals.

No clear correlation between hyperon parameters and astrophysical data.

Hyperons create tension between astrophysical and heavy-ion constraints.

Abstract

The appearance of strangeness in the form of hyperons within the inner core of neutron stars is expected to affect its detectable properties such as its global structure or gravitational wave emission. In this work, we explore the parameter space of hyperonic stars within the framework of the Relativistic Mean Field model allowed by present uncertainties in state-of-the-art nuclear and hypernuclear experimental data. We impose multi-physics constraints at different density regimes to restrict the parameter space: Chiral effective field theory, heavy-ion collision data as well as multi-messenger astrophysical observations of neutron stars. We investigate possible correlations between empirical nuclear and hypernuclear parameters, particularly the symmetry energy and its slope, with observable properties of neutron stars. We do not find a correlation for the hyperon parameters and the astrophysical data. However, the inclusion of hyperons generates a tension between the astrophysical and heavy ion data constraining considerable the available parameter space.