SwiftPointing and the Association between Gamma‐Ray Bursts and Gravitational Wave Bursts

The currently accepted model for gamma-ray burst phenomena involves theviolent formation of a rapidly rotating solar mass black hole. Gravitationalwaves should be associated with the black-hole formation, and their detectionwould permit this model to be tested, the black hole progenitor (e.g.,coalescing binary or collapsing stellar core) identified, and the origin of thegamma rays (within the expanding relativistic fireball or at the point ofimpact on the interstellar medium) located. Even upper limits on thegravitational-wave strength associated with gamma-ray bursts could constrainthe gamma-ray burst model. To do any of these requires joint observations ofgamma-ray burst events with gravitational and gamma-ray detectors. Here weexamine how the quality of an upper limit on the gravitational-wave strengthassociated with gamma-ray burst observations depends on the relativeorientation of the gamma-ray-burst and gravitational-wave detectors, and applyour results to the particular case of the Swift Burst-Alert Telescope (BAT) andthe LIGO gravitational-wave detectors. A result of this investigation is ascience-based ``figure of merit'' that can be used, together with other missionconstraints, to optimize the pointing of the Swift telescope for the detectionof gravitational waves associated with gamma-ray bursts.Comment: aastex, 14 pages, 2 figure