Superradiant scattering of electromagnetic waves emitted from disk around Kerr black holes
arXiv:1009.2193 · doi:10.1103/PhysRevD.82.084026
Abstract
We study electromagnetic perturbations around a Kerr black hole surrounded by a thin disk on the equatorial plane. Our main purpose is to reveal the black hole superradiance of electromagnetic waves emitted from the disk surface. The outgoing Kerr-Schild field is used to describe the disk emission, and the superradiant scattering is represented by a vacuum wave field which is added to satisfy the ingoing condition on the horizon. The formula to calculate the energy flux on the disk surface is presented, and the energy transport in the disk-black hole system is investigated. Within the low-frequency approximation we find that the energy extracted from the rotating black hole is mainly transported back to the disk, and the energy spectrum of electromagnetic waves observed at infinity is also discussed.
arXiv comment15 pages, 2 figures, accepted for publication in Physical Review D
References in corpus (8)
- Viewing the Shadow of the Black Hole at the Galactic Center
- Measurement of the Kerr Spin Parameter by Observation of a Compact Object's Shadow
- Shapes and Positions of Black Hole Shadows in Accretion Disks and Spin Parameters of Black Holes
- X-ray Polarization from Accreting Black Holes: II. The Thermal State
- Polarimetric Imaging of the Massive Black Hole at the Galactic Center
- Covariant Magnetoionic Theory I: Ray Propagation
- Images of the radiatively inefficient accretion flow surrounding a Kerr black hole: application in Sgr A*
- Disk illumination by black hole superradiance of electromagnetic perturbations