Pulsars as gravitational wave detectors

TL;DR

Pulsar timing arrays can detect ultra-low frequency gravitational waves by analyzing correlated signals across multiple pulsars, with ongoing projects aiming to identify these waves and understand their sources.

Contribution

This paper explains how pulsar timing arrays can unambiguously detect ultra-low frequency gravitational waves through correlated signals, detailing current projects and data analysis methods.

Findings

Current pulsar timing projects are progressing towards gravitational wave detection.

Correlated timing signals across pulsars indicate potential gravitational wave detection.

Implications of current results suggest promising future detections.

Abstract

Pulsar timing array projects are carrying out high precision observations of millisecond pulsars with the aim of detecting ultra-low frequency (~ 10^{-9} to 10^{-8} Hz) gravitational waves. We show how unambiguous detections of such waves can be obtained by identifying a signal that is correlated between the timing of different pulsars. Here we describe the ongoing observing projects, the expected sources of gravitational waves, the processing of the data and the implications of current results.