Resonant Shattering Flares as Multimessenger Probes of the Nuclear Symmetry Energy

TL;DR

This paper proposes that resonant shattering flares in neutron stars, triggered by tidal forces during mergers, can serve as multimessenger probes to constrain the nuclear symmetry energy parameters, complementing nuclear experiments.

Contribution

It introduces a method to use neutron star resonant shattering flares as multimessenger signals to constrain nuclear symmetry energy parameters.

Findings

Resonant shattering flares are sensitive to the symmetry energy profile.

Timing of flares and gravitational waves can constrain nuclear matter properties.

Constraints are competitive with current nuclear experiments.

Abstract

The behaviour of the nuclear symmetry energy near saturation density is important for our understanding of dense nuclear matter. This density dependence can be parameterised by the nuclear symmetry energy and its derivatives evaluated at nuclear saturation density. In this work we show that the core-crust interface mode of a neutron star is sensitive to these parameters, through the (density-weighted) shear-speed within the crust, which is in turn dependent on the symmetry energy profile of dense matter. We calculate the frequency at which the neutron star quadrupole ($\ell = 2$) crust-core interface mode must be driven by the tidal field of its binary partner to trigger a Resonant Shattering Flare (RSF). We demonstrate that coincident multimessenger timing of an RSF and gravitational wave chirp from a neutron star merger would enable us to place constraints on the symmetry energy parameters that are competitive with those from current nuclear experiments.