Gravitational Waves from Strange Star Core-Crust Oscillation

TL;DR

This paper models core-crust oscillations in strange stars and finds that the resulting gravitational waves are too weak to detect, implying such oscillations do not affect strange star seismology.

Contribution

It introduces a rigid model to derive gravitational waveforms from core-crust oscillations in strange stars, showing their undetectability with current and future detectors.

Findings

Gravitational waves from core-crust oscillations are extremely weak.

Such oscillations do not impact strange star seismology.

Detection of these waves is unlikely with next-generation detectors.

Abstract

According to the strange quark matter hypothesis, pulsars may actually be strange stars composed of self-bound strange quark matter. The normal matter crust of a strange star, unlike that of a normal neutron star, is supported by a strong electric field. A gap is then presented between the crust and the strange quark core. Therefore, peculiar core-crust oscillation may occur in a strange star, which can produce distinctive gravitational waves. In this paper, the waveforms of such gravitational waves are derived using a rigid model. We find that the gravitational waves are extremely weak and undetectable, even for the next-generation detectors. Therefore, the seismology of a strange star is not affected by the core-crust oscillation. Observers will have to search for other effects to diagnose the existence of the crust.