New simulations of merging binary neutron stars include details of the gravitational wave signature that should in coming years help us understand another mysterious process - short gamma-ray bursts.
The emerging science of gravitational wave astronomy is optimistically named. Astronomy depends ultimately on observations, yet the only output of gravitational wave detectors has so far been noise generated within the instruments. There is good reason, based on experimental and theoretical progress, to believe that things are about to change. As an example of progress on the theoretical side, Kenta Kiuchi of Waseda University, Yuichiro Sekiguchi of the National Astronomical Observatory, Masaru Shibata of Kyoto University (all in Japan), and Keisuke Taniguchi of the University of Wisconsin, US, report in Physical Review Letters simulations of neutron star mergers that reveal new details of the gravitational waves they are expected to emit.
[1]© (Top) NASA; (Center, Bottom) Alan Stonebraker, adapted from [1]Figure 1: Gravitational wave signals from a neutron star merger (top) in the time (center) and frequency (bottom) domains. The chirping in the gravitational wave is evident in the increased oscillation frequency toward the end of the time signal, which peaks in the frequency plot at about 6000 Hz. Such signals carry information about neutron star equation of state, binary coalesence, and black hole formation.
The effort to detect gravitational waves started humbly fifty years ago with Joe Weber's bar detectors.
[2] Today the field is a thriving example of Big Science, including large facilities
[3] in the US (LIGO) and Italy (VIRGO), smaller installations in Germany (GEO 600) and Japan (TAMA, LCGT), and potential future detectors in Australia (AIGO) and India (INDIGO). LIGO, the best funded and so far the most sensitive of these instruments, is preparing a major upgrade called Advanced LIGO.