Optimal detection strategies for measuring the stochastic gravitational radiation background with laser interferometric antennas

Issues pertaining to the optimal strategy for detecting the stochastic gravitational wave background (SGWB) with laser interferometric antennas are discussed. Analyzed are the dependence of detection sensitivity on the relative orientation of interferometers, the interferometer design, and the inherent noise of the detectors. Previously Michelson, Flanagan, and Christensen thoroughly studied such topics. This paper addresses a few remaining issues for the optimal detection of the SGWB with laser interferometers. The optimal orientation of a pair of interferometers depends on both the noise characteristics of the detectors and their physical location on the surface of the Earth. Given a pair of detectors the maximum sensitivity for detecting the SGWB also depends on the transfer function of the interferometers; the relatively narrow band dual recycling interferometers are the best choice. Correlated noise in two antennas located at a single site complicates the detection strategy, but an optimistic attitude is called for given the considerable relative size of the correlated signal. The Laser Interferometric Gravitational Wave Observatory offers exciting prospects for placing limits on the strength of the SGWB.