Gravitational waves from precessing engines in GRBs

TL;DR

This paper investigates gravitational waves generated by precessing accretion disks in gamma-ray bursts, suggesting some GRBs could be detectable by Advanced LIGO due to their gravitational wave signals.

Contribution

It models Lense-Thirring precession in GRB accretion disks and assesses the detectability of resulting gravitational waves with current detectors.

Findings

Some GRBs may produce detectable gravitational waves with Advanced LIGO.

The modeled light-curves match observed GRB microstructures.

Precession periods can be estimated from accretion disk parameters.

Abstract

In the framework of a transient accretion disk at the core of a gamma-ray burst we compute possible periods of Lense-Thirring precession. Next, we evaluate the putative gravitational waves associated with such dynamical setup. Assuming a characteristic time-profile for the gamma-ray emission of a disk-jet system, we obtain light-curves presenting a time microstructure similar to that reported in some GRB events. After adjustment of the parameters out of two specific GRBs we evaluate the detectability of the gravitational waves produced by the precession of this accretion disk. As a conclusion, our analysis shows that some GRBs are likely to be probed with Advanced LIGO.