Baryon-poor outflows from rotating black holes

Abstract

Cosmological gamma-ray bursts are probably powered by systems harboring a rotating black hole. We show that frame-dragging creates baryon-poor outflows in a differentially rotating gap along an open magnetic flux-tube with dissipation $P={\Omega }_T({\Omega }_H-2{\Omega }_T)A_{\varphi }^2$, where $2\pi A_{\varphi }$ denotes the flux in the open tube, for angular velocities ${\Omega }_H$ and ${\Omega }_T$ of the black hole and the torus, respectively. The output in photon-pair outflow will be reprocessed in an intervening hypernova progenitor wind or the ISM.

Subm PRL (revised and updated according to Phys. Rep. 345, 1 (2001))