Gravitational wave bursts induced by r-mode spin-down of hybrid stars

TL;DR

This paper proposes that rapid spin-down in hybrid stars caused by r-mode instabilities can induce structural changes, leading to gravitational wave bursts potentially linked to signals detected in 2001.

Contribution

It introduces a model connecting r-mode induced spin-down to gravitational wave bursts via phase transitions in hybrid stars.

Findings

Mini-collapses produce energetic gravitational wave bursts.

Potential explanation for 2001 detector signals.

Structural discontinuities driven by surface tension effects.

Abstract

We show that sudden variations in the composition and structure of an hybrid star can be triggered by its rapid spin-down, induced by r-mode instabilities. The discontinuity of this process is due to the surface tension between hadronic and quark matter and in particular to the overpressure needed to nucleate new structures of quark matter in the mixed phase. The consequent mini-collapses in the star can produce highly energetic gravitational wave bursts. The possible connection between the predictions of this model and the burst signal found by EXPLORER and NAUTILUS detectors during the year 2001 is also investigated.