Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre

  title={Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre},
  author={Sheperd S. Doeleman and Jonathan Weintroub and Alan E. E. Rogers and Richard L. Plambeck and Robert W. Freund and Remo P. J. Tilanus and Per Friberg and Lucy M Ziurys and James M. Moran and Brian E. Corey and K. H. Young and D. L. Smythe and Michael Titus and Daniel P. Marrone and Roger J. Cappallo and Douglas C.-J. Bock and Geoffrey C. Bower and Richard A. Chamberlin and G. R. Davis and Thomas P. Krichbaum and James W. Lamb and Holly L. Maness and A. E. Niell and Alan L. Roy and Peter A. Strittmatter and Dan Werthimer and Alan R. Whitney and David P. Woody},
The cores of most galaxies are thought to harbour supermassive black holes, which power galactic nuclei by converting the gravitational energy of accreting matter into radiation. Sagittarius A* (Sgr A*), the compact source of radio, infrared and X-ray emission at the centre of the Milky Way, is the closest example of this phenomenon, with an estimated black hole mass that is 4,000,000 times that of the Sun. A long-standing astronomical goal is to resolve structures in the innermost accretion… 

Toward the event horizon—the supermassive black hole in the Galactic Center

The center of our Galaxy hosts the best constrained supermassive black hole in the universe, Sagittarius A* (Sgr A*). Its mass and distance have been accurately determined from stellar orbits and

A gas cloud on its way towards the supermassive black hole at the Galactic Centre

The presence of a dense gas cloud approximately three times the mass of Earth that is falling into the accretion zone of Sagittarius A*, a compact radio source at the Galactic Centre, is reported.

Jet-Launching Structure Resolved Near the Supermassive Black Hole in M87

Radio interferometry observations of the elliptical galaxy M87 are reported that spatially resolve the base of the jet in this source, suggesting that the M87 jet is powered by an accretion disk in a prograde orbit around a spinning black hole.

Detection of jet launching structure near the supermassive black hole in M 87

Approximately 10% of active galactic nuclei (AGN) exhibit relativistic jets, which are powered by accretion of matter onto super massive black holes. While the measured width profiles of such jets on


The 6 × 10 9 M ⊙ ?> supermassive black hole at the center of the giant elliptical galaxy M87 powers a relativistic jet. Observations at millimeter wavelengths with the Event Horizon Telescope have


In accretion-based models for Sgr A*, the X-ray, infrared, and millimeter emission arise in a hot, geometrically thick accretion flow close to the black hole. The spectrum and size of the source

The jet in the galactic center: An ideal laboratory for magnetohydrodynamics and general relativity

Abstract Of all possible black hole sources, the event horizon of the Galactic Center black hole, Sgr A*, subtends the largest angular scale on the sky. It is therefore a prime candidate to study and

Observing a black hole event horizon: (sub)millimeter VLBI of Sgr A*

Abstract Very strong evidence suggests that Sagittarius A*, a compact radio source at the center of the Milky Way, marks the position of a super massive black hole. The proximity of Sgr A* in

Resolved magnetic-field structure and variability near the event horizon of Sagittarius A*

Interferometric observations at 1.3-millimeter wavelength are reported that spatially resolve the linearly polarized emission from the Galactic Center supermassive black hole, Sagittarius A*.

The Post-pericenter Evolution of the Galactic Center Source G2

In early 2014, the fast-moving near-infrared source G2 reached its closest approach to the supermassive black hole Sgr A* in the Galactic center. We report on the evolution of the ionized gaseous



On the Nature of the Compact Dark Mass at the Galactic Center

We consider a model in which Sgr A*, the 3.7 × 106 M☉ supermassive black hole candidate at the Galactic center, is a compact object with a thermally emitting surface. For very compact surfaces within

Simulating the emission and outflows from accretion discs

The radio source Sagittarius A* (Sgr A*) is believed to be a hot, inhomogeneous, magnetized plasma flowing near the event horizon of the 3.6 × 106 M⊙ black hole at the galactic centre. At a distance

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

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

A size of ∼1 au for the radio source Sgr A* at the centre of the Milky Way

Although it is widely accepted that most galaxies have supermassive black holes at their centres, concrete proof has proved elusive. Sagittarius A* (Sgr A*), an extremely compact radio source at the

A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way

Ten years of high-resolution astrometric imaging allow us to trace two-thirds of the orbit of the star currently closest to the compact radio source (and massive black-hole candidate) Sagittarius A* and show that the star is on a bound, highly elliptical keplerian orbit around Sgr A*.

The jet model for Sgr A*: radio and X-ray spectrum

The preliminary detection of the Galactic Center black hole Sgr A* in X-rays by the Chandra mission, as well as recent mm-VLBI measurements, impose strict constraints on this source. Using a

Detection of the Intrinsic Size of Sagittarius A* Through Closure Amplitude Imaging

We have detected the intrinsic size of Sagittarius A*, the Galactic center radio source associated with a supermassive black hole, showing that the short-wavelength radio emission arises from very

Dynamical Constraints on Alternatives to Supermassive Black Holes in Galactic Nuclei

The compelling dynamical evidence for massive dark objects in galactic nuclei does not uniquely imply massive black holes (BHs). To argue convincingly that these objects are BHs we must rule out

The flare activity of Sagittarius A : New coordinated mm to X-ray observations

Context. We report new simultaneous near-infrared/sub-millimeter/X-ray observations of the Sgr A* counterpart associated with the massive 3−4 × 10 6 Mblack hole at the Galactic Center. Aims. We

Inward Bound—The Search for Supermassive Black Holes in Galactic Nuclei

Dynamical searches reveal central dark objects with masses"" 106 to 109.5 M0 in the Galaxy, M31, M32, M87, NGC 3115, NGC 3377, NGC 4258, and NGC 4594. Indirect arguments suggest but do not prove that