Related papers: The Galactic Center
The Galactic Centre has been studied with the High Energy Stereoscopic System (H.E.S.S.) for over 10 years, revealing a bright, complex gamma-ray morphology. Besides a strong point-like very-high-energy gamma-ray source coincident with the…
The black hole at the center of our Milky Way Galaxy -- the Galactic Black Hole, or GBH -- is a rather modest representative of its class. With a mass of 4 x 10^6 solar masses, it is well over a thousand times less massive than the most…
We report the detection of Sagittarius A*, the radio source associated with our Galaxy's central massive black hole, at 330 MHz with the Very Large Array. Implications for the spectrum and emission processes of Sagittarius A* are discussed…
The evidence for the presence of a concentration of dark matter at the Galactic center is now very compelling. There is no question that the stellar and gas kinematics within 0.01 pc is dominated by under-luminous matter in the form of…
Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large…
The centre of the Milky Way is occupied by a nuclear star cluster, which contains the supermassive black hole Sgr A*. The cluster is embedded in the larger surrounding nuclear stellar disc. These three components dominate the mass budget of…
Sagittarius A* (Sgr A*) is the supermassive black hole residing at the center of the Milky Way. It has been the main target of an extensive multiwavelength campaign we carried out in April 2007. Herein, we report the detection of a bright…
The massive Galactic black hole and the stars around it are a unique laboratory for studying how relaxation processes lead to close interactions of stars and compact remnants with the central massive black hole, in particular those leading…
Submilliarcsecond astrometry and imaging of the black hole Sgr A* at the Galactic Center may become possible in the near future at infrared and submillimetre wavelengths. This resolution is sufficient to observe the silhouette the…
We show that with a Next Generation Large Telescope one can detect the accelerated motions of ~100 stars orbiting the massive black hole at the Galactic center. The positions and velocities of these stars will be measured to astrometric and…
The massive black hole at the Galactic Centre is known to be variable in radio, millimeter, near-IR and X-rays. We investigate the physical processes responsible for the variable observed emissions from the compact radio source Sgr A*. We…
Precision measurements of the stars in short-period orbits around the supermassive black hole at the Galactic Center are now being used to constrain general relativistic effects, such as the gravitational redshift and periapse precession.…
One of the most interesting astronomical objects is the Galactic Center. We concentrate our discussion on a theoretical analysis of observational data of bright stars in the IR-band obtained with large telescopes. We also discuss the…
Proper motion studies of stars in the centre of the Milky Way have been typically limited to the Arches and Quintuplet clusters and to the central parsec. Here, we present the first results of a large-scale proper motion study of stars…
We summarize the current state of polarization observations of Sagittarius A*, the compact radio source and supermassive black hole candidate in the Galactic Center. These observations are providing new tools for understanding accretion…
Sgr A* at the Galactic Center is a puzzling source. It has a mass M=(2.5+/-0.4) x 10^6 solar masses which makes it an excellent black hole candidate. Observations of stellar winds and other gas flows in its vicinity suggest a mass accretion…
We summarize basic observational results on Sagittarius~A* obtained from the radio, infrared and X-ray domain. Infrared observations have revealed that a dusty S-cluster object (DSO/G2) passes by SgrA*, the central super-massive black hole…
The supermassive black hole at the Galactic center, Sagittarius A*, has experienced periods of higher activity in the past. The reflection of these past outbursts is observed in the molecular material surrounding the black hole but…
The centre of our galaxy hosts the nearest super-massive black hole to the solar system, identified to the compact radio source Sgr A*. High energy experiments have tried in the past to detect the X/gamma-ray emission expected from the…
We present the results of 16 years of monitoring stellar orbits around the massive black hole in center of the Milky Way using high resolution NIR techniques. This work refines our previous analysis mainly by greatly improving the…