Hyperons in neutron star mergers

TL;DR

This paper investigates how hyperons in hot, dense matter affect gravitational wave signals from neutron star mergers, revealing a detectable frequency shift that could indicate hyperon presence.

Contribution

It demonstrates that hyperonic equations of state cause a systematic shift in post-merger gravitational wave frequencies, providing a new method to detect hyperons.

Findings

Hyperonic equations cause up to 150 Hz shift in dominant GW frequency.

The shift is detectable with current advanced gravitational wave detectors.

Hyperons influence the thermal behavior of dense matter in mergers.

Abstract

We discuss the effects induced by the potential presence of hyperons in hot and ultra-dense matter within the context of neutron star mergers. Specifically, we address their effect on the dominant post-merger frequency of the gravitational waves. By performing a simulation campaign with a large sample of hyperonic and nucleonic equations of state, we explicitly show that the unique thermal behavior of hyperonic equations of state results in a systematic shift of the dominant frequency with respect to the nucleonic reference level. The predicted shift has values of up to 150 Hz, and it could be detected with the newest generations of gravitational wave detectors. Thus this approach opens a new path for signaling the presence of hyperons in neutron star remnant matter.