Very High-Energy Emission from the Direct Vicinity of Rapidly Rotating Black Holes

Very High-Energy Emission from the Direct Vicinity of Rapidly Rotating Black Holes

Blog Article

When a black hole accretes plasmas at very low accretion rate, an advection-dominated accretion flow (ADAF) is formed.In an ADAF, relativistic electrons emit soft gamma-rays via Bremsstrahlung.Some MeV photons collide with each other to materialize as electron-positron pairs in the magnetosphere.Such pairs efficiently screen the electric field along the magnetic field lines, when the accretion rate cosmetic case is typically greater than 0.

03⁻0.3% of the Eddington rate.However, when the accretion rate becomes smaller than this value, the number density of the created pairs becomes less than the rotationally induced Goldreich⁻Julian density.In such a charge-starved magnetosphere, an electric field Fan Assembly arises along the magnetic field lines to accelerate charged leptons into ultra-relativistic energies, leading to an efficient TeV emission via an inverse-Compton (IC) process, spending a portion of the extracted hole’s rotational energy.

In this review, we summarize the stationary lepton accelerator models in black hole magnetospheres.We apply the model to super-massive black holes and demonstrate that nearby low-luminosity active galactic nuclei are capable of emitting detectable gamma-rays between 0.1 and 30 TeV with the Cherenkov Telescope Array.