Polarization angle swings in photons near a Kerr black hole during ringdown lock in time to quasi-normal modes with amplitudes up to about 10 degrees.
Imaging Bright Spots in the Accretion Flow Near the Black Hole Horizon of Sgr A*
4 Pith papers cite this work. Polarity classification is still indexing.
4
Pith papers citing it
abstract
Images from the vicinity of the black hole horizon at the Galactic centre (Sgr A*) could be obtained in the near future with a Very Large Baseline Array of sub-millimetre telescopes. The recently observed short-term infrared and X-ray variability of the emission from Sgr A* implies that the accretion flow near the black hole is clumpy or unsteady. We calculate the appearance of a compact emission region (bright spot) in a circular orbit around a spinning black hole as a function of orbital radius and orientation. We find that the mass and spin of the black hole can be extracted from their generic signatures on the spot image as well as on the lightcurves of its observed flux and polarisation. The strong-field distortion remains noticeable even when the spot image is smoothed over the expected ~20 microarcsecond resolution of future sub-millimetre observations.
citation-role summary
background 3
citation-polarity summary
roles
background 3polarities
background 3representative citing papers
Corotating point sources on accretion disks near black holes distort the relative magnification factor distribution, modulating caustics and encoding accretion flow kinematics via time-delayed images.
Current and future observations can test whether dark compact objects are Kerr black holes or exotic alternatives, with null results strengthening the black hole paradigm.
citing papers explorer
-
Black Hole Ringdown Seen in Photon Polarization Swings
Polarization angle swings in photons near a Kerr black hole during ringdown lock in time to quasi-normal modes with amplitudes up to about 10 degrees.
- Polarization Signatures of Inspiraling Hotspots around Kerr Black Holes