title: Prospects for direct detection of the circular polarization of the gravitational-wave background.
abstract: We discuss the prospects for directly detecting a circular polarization signal of the gravitational-wave background. We find it is generally difficult to probe the monopole mode of the signal due to the broad directivity of the gravitational-wave detectors. But the dipole (l=1) and octupole (l=3) modes of the signal can be measured in a simple manner by combining outputs of two unaligned detectors, and we can dig them deeply under confusion and detector noises. Around f approximately 0.1 mHz the Laser Interferometer Space Antenna will provide ideal data streams to detect these patterns whose magnitudes are as small as approximately 1 percent of the detector noise level in terms of the nondimensional energy density OmegaGW(f).
authors.affiliation: Department of Physics and Astronomy, 4186 Frederick Reines Hall, University of California, Irvine, California 92697, USA.
authors.forename: Naoki
authors.initials: N
authors.lastname: Seto