Detection of Gamma Rays from a Starburst Galaxy
Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~1015 electron volts. We report the…
Very high energy γ-ray observations of the binary PSR B1259-63/SS2883 around the 2007 Periastron
Aims: This article presents very-high-energy (VHE; E > 100 GeV) data from the γ-ray binary PSR B1259-63 as taken during the years 2005, 2006 and before as well as shortly after the 2007 periastron…
Radio Imaging of the Very-High-Energy γ-Ray Emission Region in the Central Engine of a Radio Galaxy
The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 1012 electron…
Spectrum and variability of the Galactic center VHE γ-ray source HESS J1745-290
Aims: A detailed study of the spectrum and variability of the source HESS J1745-290 in the Galactic Center (GC) region using new data from the H.E.S.S. array of Cherenkov telescopes is presented. Flaring activity…
Simultaneous multiwavelength observations of the second exceptional γ-ray flare of PKS 2155-304 in July 2006
Aims: The X-ray-TeV connection and the evolution of the emitting particle population is studied in high-energy peaked BL Lac objects, by obtaining spectral information in both bands on sub-hour timescales. Methods: Simultaneous observations with…
Constraints on the multi-TeV particle population in the Coma galaxy cluster with HESS observations
Aims: Galaxy clusters are key targets in the search for ultra high energy particle accelerators. The Coma cluster represents one of the best candidates for such a search owing to its high mass, proximity,…
Detection of very high energy radiation from HESS J1908+063 confirms the Milagro unidentified source MGRO J1908+06
Aims: Detection of a γ-ray source above 300 GeV is reported, confirming the unidentified source MGRO J1908+06, discovered by the Milagro collaboration at a median energy of 20 TeV. Methods: The source was observed…
Simultaneous Observations of PKS 2155-304 with HESS, Fermi, RXTE, and Atom: Spectral Energy Distributions and Variability in a Low State
We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155−304. The gamma-ray bands were observed for 11 days, between 2008 August 25…
HESS upper limit on the very high energy γ-ray emission from the globular cluster 47 Tucanae
Observations of the globular cluster 47 Tucanae (NGC 104), which contains at least 23 ms pulsars, were performed with the HESS telescope system. The observations lead to an upper limit of F(E>800 GeV) <…
Discovery of Very High Energy γ-Ray Emission from Centaurus A with H.E.S.S.
We report the discovery of faint very high energy (VHE; E > 100 GeV) γ-ray emission from the radio galaxy Centaurus A in observations performed with the High Energy Stereoscopic System (H.E.S.S.) experiment, an imaging…
