Gravitational Waves from Stellar Collapse: Correlations to Explosion Asymmetries

The collapse of massive stars not only produces observable outbursts acrossthe entire electromagnetic spectrum but, for Galactic (or near-Galactic)supernovae, detectable signals for ground-based neutrino and gravitational wavedetectors. Gravitational waves and neutrinos provide the only means to studythe actual engine behind the optical outbursts: the collapsed stellar core.While the neutrinos are most sensitive to details of the equation of state,gravitational waves provide a means to study the mass asymmetries in thiscentral core. We present gravitational wave signals from a series of3-dimensional core-collapse simulations with asymmetries derived from initialperturbations caused by pre-collapse convection, core rotation, and low-modeconvection in the explosion engine itself. A Galactic supernovae will allow usto differentiate these different sources of asymmetry. Combining this signalwith other observations of the supernova, from neutrinos to gamma-rays to thecompact remnant, dramatically increases the predictive power of thegravitational wave signal. We conclude with a discussion of the gravitationalwave signal arising from collapsars, the leading engine for long-durationgamma-ray bursts.Comment: 36 pages including 14 figures, accepted by Ap