Detecting the Stochastic Gravitational Wave Background Using Pulsar Timing

The direct detection of gravitational waves is a major goal of currentastrophysics. We provide details of a new method for detecting a stochasticbackground of gravitational waves using pulsar timing data. Our results showthat regular timing observations of 40 pulsars each with a timing accuracy of100 nano-seconds will be able to make a direct detection of the predictedstochastic background from coalescing black holes within five years. With animproved pre-whitening algorithm, or if the background is at the upper end ofthe predicted range, a significant detection should be possible with only 20pulsars.Comment: Accepted by ApJ Letter