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Energy extraction from boosted black holes: Penrose process, jets, and the membrane at infinity
Robert F. Penna
Numerical simulations indicate that black holes carrying linear momentum and/or orbital momentum can power jets. The jets extract the kinetic energy stored in the black hole's moti…
Black hole jet power from impedance matching
Robert F. Penna
Black hole jet power depends on the angular velocity of magnetic field lines, . Force-free black hole magnetospheres typically have , where is the a…
The Black Hole Meissner Effect and Blandford-Znajek Jets
Robert F. Penna
Spinning black holes tend to expel magnetic fields. In this way they are similar to superconductors. It has been a persistent concern that this black hole "Meissner effect" could q…
A new equilibrium torus solution and GRMHD initial conditions
Robert F. Penna, Akshay Kulkarni, Ramesh Narayan
General relativistic magnetohydrodynamic (GRMHD) simulations are providing influential models for black hole spin measurements, gamma ray bursts, and supermassive black hole feedba…
General Relativistic Magnetohydrodynamic Simulations of Blandford-Znajek Jets and the Membrane Paradigm
Robert F. Penna, Ramesh Narayan, Aleksander Sadowski
Recently it has been observed that the scaling of jet power with black hole spin in galactic X-ray binaries is consistent with the predictions of the Blandford-Znajek (BZ) jet mode…
Energy, momentum and mass outflows and feedback from thick accretion discs around rotating black holes
A. Sadowski, R. Narayan, R. Penna +1
Using long-duration general relativistic magnetohydrodynamic simulations of radiatively inefficient accretion discs, the energy, momentum and mass outflow rates from such systems a…