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

  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},
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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Testing Accretion Physics and Strong-Field Gravity by Imaging Accreting Black Holes
  • 2008
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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
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.
On the Nature of the Variable Infrared Emission from Sagittarius A
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
Rapid X-ray flaring from the direction of the supermassive black hole at the Galactic Centre
The discovery of rapid X-ray flaring from the direction of Sagittarius A* provides compelling evidence that the emission is coming from the accretion of gas onto a supermassive black hole at the Galactic Centre.
A new X-ray flare from the galactic nucleus detected with the XMM-Newton photon imaging cameras
Sgr A*, the compact radio source believed to be the counterpart of the massive black hole at the Galactic nucleus, was observed to undergo rapid and intense flaring activity in X-rays with Chandra in
Viewing the Shadow of the Black Hole at the Galactic Center.
In recent years, evidence for the existence of an ultracompact concentration of dark mass associated with the radio source Sagittarius A* in the Galactic center has become very strong. However,
Fluorescent iron lines as a probe of astrophysical black hole systems
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Direct Imaging of the Massive Black Hole, SgrA^*(Session 5 : Evidence for Giant Black Holes)
Imaging the vicinity of black hole is one of the ultimate goals of VLBI astronomy. The closest massive black hole, SgrA*, located at Galactic center is the leading candidate for such observations.
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The observed iron Kα fluorescence lines in Seyfert 1 galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the emission. Here we present an analysis of