The Sensitivity of the Parkes Pulsar Timing Array to Individual Sources of Gravitational Waves

TL;DR

This paper evaluates the sensitivity of the Parkes Pulsar Timing Array to gravitational waves from super-massive black-hole binaries, providing constraints on merger rates and discussing future prospects with the SKA telescope.

Contribution

It offers a detailed analysis of pulsar timing sensitivity to individual gravitational wave sources and includes a study of the effects of fitting pulsar timing models.

Findings

Sky-averaged constraint: less than one merger every seven years for certain black-hole binaries.

Sensitivity at nanoHertz frequencies complements LIGO and LISA.

Discussion of future detection prospects with the Square Kilometre Array.

Abstract

We present the sensitivity of the Parkes Pulsar Timing Array to gravitational waves emitted by individual super-massive black-hole binary systems in the early phases of coalescing at the cores of merged galaxies. Our analysis includes a detailed study of the effects of fitting a pulsar timing model to non-white timing residuals. Pulsar timing is sensitive at nanoHertz frequencies and hence complementary to LIGO and LISA. We place a sky-averaged constraint on the merger rate of nearby ($z < 0.6$) black-hole binaries in the early phases of coalescence with a chirp mass of $10^{10}\,\rmn{M}_\odot$ of less than one merger every seven years. The prospects for future gravitational-wave astronomy of this type with the proposed Square Kilometre Array telescope are discussed.