Gravitational Waves from GRB Core Spindown

TL;DR

This paper models gravitational wave emissions from the core spin-down of GRBs, linking electromagnetic signatures with potential detectable gravitational wave signals during specific burst phases.

Contribution

It introduces a novel electrodynamic model connecting gamma-ray burst features with gravitational wave signatures from core distortions.

Findings

Predicted gravitational wave profiles during GRB phases

Identification of specific time intervals for LIGO data analysis

Correlation between magnetic field winding and wave emission

Abstract

We investigate long Gamma-Ray Bursts (GRB) which manifest a sharp linear rise followed by an exponential decay in their gamma-ray prompt emission observed with the BAT instrument on board the Swift satellite. We offer a simple electrodynamic model that may account for these particular characteristics. We associate the sharp rise with the winding of the magnetic field by the fast rotating core that formed in the interior of the stellar precursor. We also associate the subsequent exponential decay with the electromagnetic spin-down of the core following the release of the electromagnetic jet from the stellar interior. Any non-axisymmetric distortion in the rotating core will generate gravitational waves with exponentially decreasing frequency, a so-called "down-chirp". We obtain a detailed estimate of the gravitational wave profile if the distortion of spacetime is due to the winding of a non-axisymmetric component of the magnetic field during that particular phase of the burst. We offer 7 particular time intervals during which one may look into LIGO archival data for the presence of our particular predicted waveforms in order to test our interpretation.