High priority targets for transient gravitational waves from glitching pulsars

TL;DR

This paper evaluates the potential detectability of gravitational waves from glitching pulsars using various models, providing analytical tools and identifying promising pulsars like Vela for current and future detectors.

Contribution

It introduces six models for transient gravitational wave emission from pulsar glitches and develops an analytical SNR approximation considering sky position, enhancing detection predictions.

Findings

Certain models predict detectable signals in O4.

Vela pulsar is the most promising source.

PSR J0537-6910 may be detectable with next-gen detectors.

Abstract

Glitching pulsars are expected to be important sources of gravitational waves. In this paper, we explore six different models that propose the emission of transient continuous waves, lasting days to months, coincident with glitches. The maximal gravitational wave energy is calculated for each model, which is then used to determine whether associated gravitational waves could be detectable with LIGO-Virgo-KAGRA's O4 detectors. We provide an analytical approximation to calculate the signal-to-noise ratio which includes information about the source's sky position, improving on previous estimates that assume isotropic or sky and orientation averaged sensitivities. By analysing the entire glitching population, we find that certain models predict detectable signals in O4, whereas others do not. We also rank glitching pulsars by signal-to-noise ratio, based on archival data, and we find that for all models, the Vela pulsar (PSR J0835$-$4510) would provide the strongest signal. Moreover, PSR J0537$-$6910 is not expected to yield a detectable signal in O4, but will start becoming relevant for next generation detectors. Our analysis also extends to the entire pulsar population, regardless of whether they have glitched, and we provide a list of pulsars that would present a significant signal, if they were to glitch. Finally, we apply our analysis to the April 2024 Vela glitch and find that a signal should be detectable under certain models. The non-detection of a supposedly detectable signal would provide an efficiency factor that quantifies a model's contribution to gravitational wave emission, eventually leading to a differentiation of models and independent constraints on physical parameters.