Calorimetry of gamma-ray bursts: Echoes in gravitational waves

Black holes surrounded by a disk or torus may drive the enigmatic cosmologi cal gamma-ray bursts (GRBs). Equivalence in poloidal topology to pulsar mag netospheres shows a high incidence of the black hole luminosity L-H into th e surrounding magnetized matter. We argue that this emission is reradiated into gravitational waves at L-GW similar or equal to L-H/2 in frequencies o n the order of 1 kHz, winds, and, potentially, MeV neutrinos. The total ene rgy budget and input to the GRB from baryon-poor jets are expected to be st andard in this scenario, consistent with recent analysis of afterglow data. Collimation of these outflows by baryon-rich disk or torus winds may accou nt for the observed spread in opening angles up to about 35 degrees. This m odel may be tested by future LIGO/VIRGO observations.