Imaging optically-thin hotspots near the black hole horizon of Sgr A* at radio and near-infrared wavelengths

@article{Broderick2006ImagingOH,
  title={Imaging optically-thin hotspots near the black hole horizon of Sgr A* at radio and near-infrared wavelengths},
  author={Avery E. Broderick and Abraham Loeb Institute for Theory and Computation and Harvard University},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2006},
  volume={367},
  pages={905-916}
}
Submilliarcsecond astrometry and imaging of the black hole Sgr A* at the Galactic Centre may become possible in the near future at infrared and submillimetre wavelengths. Motivated by the observations of short-term infrared and X-ray variability of Sgr A*, in a previous paper, we computed the expected images and light curves, including polarization, associated with a compact emission region orbiting the central black hole. We extend this work, using a more realistic hotspot model and including… 
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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 submillimetre telescopes. The recently
Near-infrared flares from accreting gas around the supermassive black hole at the Galactic Centre
TLDR
High-resolution infrared observations of Sagittarius A* reveal ‘quiescent’ emission and several flares, and traces very energetic electrons or moderately hot gas within the innermost accretion region.
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Recent infrared (IR) observations of the center of our Galaxy indicate that the supermassive black hole (SMBH) source Sgr A* is strongly variable in the IR. The timescale for the variability, ~30
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