Related papers: Sgr A* Observations with H.E.S.S. II
The Milky Way centre hosts a supermassive Black Hole (BH) with a mass of ~4*10^6 M_Sun. Sgr A*, its electromagnetic counterpart, currently appears as an extremely weak source with a luminosity L~10^-9 L_Edd. The lowest known Eddington ratio…
Results from gamma-ray observations by the H.E.S.S. telescope array in the direction of the young stellar cluster Westerlund 2 are presented. Stereoscopic imaging of Cherenkov light emission of gamma-ray induced showers in the atmosphere is…
The diffuse very high-energy (VHE, > 100 GeV) gamma-ray emission observed in the central 200 pc of the Milky Way by H.E.S.S. was found to follow the dense matter distribution in the Central Molecular Zone (CMZ) up to a longitudinal distance…
We present ALMA observations at 233, 678, and 870 GHz of the Galactic Center black hole, Sagittarius A*. These observations reveal a flat spectrum over this frequency range with spectral index $\alpha \approx -0.3$, where the flux density…
We present the results of the most comprehensive survey of the Galactic plane in very high-energy (VHE) gamma-rays, including a public release of Galactic sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE…
The High Energy Spectroscopic System (H.E.S.S.) is pursuing a rich observational program in astroparticle physics. The latest results from H.E.S.S. on the search for dark matter towards the Galactic Center and dwarf galaxies, the test of…
The H.E.S.S. experiment (High Energy Stereoscopic System) is a new generation atmospheric Cherenkov detector measuring high-energy (>100 GeV) gamma radiation from the Universe. This paper briefly explains the imaging Cherenkov technique and…
In this article we summarise and discuss the infrared, radio, and X-ray emission from the supermassive black hole in the Galactic Centre, SgrA*. We include new results from near-infrared polarimetric imaging observations obtained on May…
We have observed the central 45' region of the Galaxy at 620 MHz band of the Giant Metrewave Radio Telescope (GMRT) in radio continuum, and measured the polarisation properties of 64 small diameter background extragalactic sources seen…
The Galactic Center was observed at 8.6 mum in order to detect a mid-infrared (MIR) counterpart of Sgr A*, parallel to NIR observations. The goal was to set constraints on possible emission mechanisms.Imaging data were acquired with the…
The recent detection of significant linear polarization at mm and sub-mm wavelengths in the spectrum of Sgr A* (if confirmed) will be a useful probe of the conditions within several Schwarzschild radii ($r_S$) of the event horizon at the…
Very high-energy gamma-rays (VHE; E>100 GeV) have been detected from the direction of the Galactic Centre up to energies E>10 TeV. Up to now, the origin of this emission is unknown due to the limited positional accuracy of the observing…
Sgr A East is a supernova remnant located within few parsecs from the Galactic Centre (GC). There are good reasons to believe that this object is the source of the gamma-ray excess detected by HESS in the direction of the GC meaning that…
We report on recent near-infrared (NIR) and X-ray observations of Sagittarius A* (Sgr A*), the electromagnetic manifestation of the ~4x10^6 solar masses super-massive black hole (SMBH) at the Galactic Center. The goal of these coordinated…
With its extreme density of stars and stellar remnants, dense young massive clusters, high specific star formation rate, intense radiation field, high magnetic field strength, and properties of the interstellar medium that resemble those in…
Recent observations of the Galactic center in high-energy gamma-rays (above 0.1TeV) have opened up new ways to study this region, from understanding the emission source of these high-energy photons to constraining the environment in which…
Very-high-energy (VHE; >~100 GeV) gamma-rays are expected from gamma-ray bursts (GRBs) in some scenarios. Exploring this photon energy regime is necessary for understanding the energetics and properties of GRBs. GRBs have been one of the…
Employing data collected during the first 25 months' observations by the Fermi-LAT, we describe and subsequently seek to model the very high energy (>300 MeV) emission from the central few parsecs of our Galaxy. We analyze the…
The construction of the H.E.S.S. (High Energy Stereoscopic System), a superior system of four 12 m imaging atmospheric Cherenkov telescopes, has been completed recently in the Namib desert close to Windhoek, at 1800 m above sea level. This…
Stochastic acceleration of electrons interacting resonantly with a turbulent magnetic field in a small accretion torus appears to be the likely mechanism responsible for much of Sagittarius A*'s millimeter and shorter wavelength spectrum.…