Gravitational waves from the Papaloizou-Pringle instability in black hole-torus systems

Understand

Black hole (BH)--torus systems are promising candidates for the central engine of gamma-ray bursts (GRBs), and also possible outcomes of the collapse of supermassive stars to supermassive black holes (SMBHs).

• By three-dimensional general relativistic numerical simulations, we show that an $m=1$ nonaxisymmetric instability grows for a wide range of self-gravitating tori orbiting BHs.
• The resulting nonaxisymmetric structure persists for a timescale much longer than the dynamical one, becoming a strong emitter of large amplitude, quasiperiodic gravitational waves.
• Our results indicate that both, the central engine of GRBs and newly formed SMBHs, can be strong gravitational wave sources observable by forthcoming ground-based and spacecraft detectors.