Polarized gravitational waves from gamma-ray bursts

Significant gravitational-wave emission is expected from gamma-ray bursts arising from compact stellar mergers and possibly also from bursts associated with fast-rotating massive stellar core collapses. These models have in common a high angular rotation rate, and observations provide evidence for jet collimation of the photon emission, with properties depending on the polar angle. Here we consider the gravitational-wave emission and its polarization as a function of angle that is expected from such sources. We discuss possible correlations between the burst photon luminosity or the delay between gravitational-wave bursts and X-ray flashes and the polarization degree of the gravitational waves.