Resonant shattering flares as multimessenger probes of the nuclear symmetry energy

The behaviour of the nuclear symmetry energy near saturation density is important for our understanding of dense nuclear matter. This density dependence can be parametrized 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 (l = 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.

Automated summary

The behavior of nuclear symmetry energy near saturation density is crucial for understanding dense nuclear matter. This study demonstrates the sensitivity of the core-crust interface mode of a neutron star to these parameters, showing that coincident multimessenger timing of a resonant shattering flare and gravitational wave chirp from a neutron star merger can place competitive constraints on symmetry energy parameters.