Searching for gravitational waves from the Crab pulsar - the problem of timing noise

TL;DR

This paper investigates the challenges of detecting gravitational waves from the Crab pulsar due to its timing noise and proposes a method to account for phase wander in data analysis.

Contribution

It introduces a heterodyning method that incorporates timing noise for improved gravitational wave searches from the Crab pulsar.

Findings

The phase evolution of the Crab pulsar deviates from simple models due to timing noise.

A heterodyning technique is proposed to track phase wander in gravitational wave data.

Discussion on using electromagnetic and gravitational observations to understand pulsar noise.

Abstract

Of the current known pulsars, the Crab pulsar (B0531+21) is one of the most promising sources of gravitational waves. The relatively large timing noise of the Crab causes its phase evolution to depart from a simple spin-down model. This effect needs to be taken in to account when performing time domain searches for the Crab pulsar in order to avoid severely degrading the search efficiency. The Jodrell Bank Crab pulsar ephemeris is examined to see if it can be used for tracking the phase evolution of any gravitational wave signal from the pulsar, and we present a method of heterodyning the data that takes account of the phase wander. The possibility of obtaining physical information about the pulsar from comparisons of the electromagnetically and a gravitationally observed timing noise is discussed. Finally, additional problems caused by pulsar glitches are discussed.