Gravitational-wave signatures in successful vs. failed core-collapse supernovae

In this contribution, we discuss possible gravitational-wave (GWs) signatures emitted from core-collapse supernovae that do or do not produce explosions. For the former case, we study properties of GWs based on the three-dimensional (3D) supernova simulations, which demonstrate the neutrino-driven explosions aided by the standing accretion shock instability (SASI). By taking into account the effects of stellar rotation, we find that the gravitational waveforms from neutrinos in models that include rotation exhibit a common feature otherwise they vary much more stochastically in the absence of rotation. We point out that a recently proposed future space interferometers like Fabry-Perot type DECIGO would permit the detection of these signals for a Galactic supernova. For the black-hole forming supernovae, we study the GW emission based on a long-term special relativistic magnetohydrodynamic simulation in the light of collapsar model of long-duration gamma-ray bursts (GRBs). We find that the GWs from anisotropic neutrino emission illuminated by accretion disk become as high as the GWs contributed from matter motions of accreting material. These signals, possibly visible to the BBO-class detectors for a hundred Megaparsec distance scales, may give us an important probe into the central engines of GRBs.