I. Büsching

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Context. The Crab nebula was observed with the HESS stereoscopic Cherenkov-telescope array between October 2003 and January 2005 for a total of 22.9 h (after data quality selection). This period of time partly overlapped with the commissioning phase of the experiment; observations were made with three operational telescopes in late 2003 and with the(More)
The Vela supernova remnant (SNR) is a complex region containing a number of sources of non-thermal radiation. The inner section of this SNR, within 2 degrees of the pulsar PSR B0833−45, has been observed by the H.E.S.S. γ-ray atmospheric Cherenkov detector in 2004 and 2005. A strong signal is seen from an extended region to the south of the pulsar, within(More)
Aims. The BL Lac object RGB J0152+017 (z = 0.080) was predicted to be a very high-energy (VHE; > 100 GeV) γ-ray source, due to its high X-ray and radio fluxes. Our aim is to understand the radiative processes by investigating the observed emission and its production mechanism using the High Energy Stereoscopic System (H.E.S.S.) experiment. Methods. We(More)
The detection of fast variations of the tera-electron volt (TeV) (10(12) eV) gamma-ray flux, on time scales of days, from the nearby radio galaxy M87 is reported. These variations are about 10 times as fast as those observed in any other wave band and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central(More)
The recent discovery of diffuse, VHE γ radiation from the Galactic center ridge by the H.E.S.S. telescope allow for the first time the direct determination of parameters of galactic cosmic ray propagation models. In this paper we show that the diffuse γ-radiation near the Galactic center may be explained by the interaction of VHE cosmic ray (CR) protons(More)
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 − 6) × 10 9 M) provides a unique opportunity to investigate the origin of very high energy (VHE; E>100 GeV) γ-ray emission generated in relativistic outflows and the surroundings of super-massive black holes. M 87 has been established as a VHE γ-ray emitter(More)
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 approximately 10(15) electron volts. We report the detection of gamma rays--tracers of such cosmic rays--from the starburst galaxy NGC 253 using the High Energy Stereoscopic System(More)
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 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we(More)
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 H.E.S.S. experiment, an imaging atmospheric Cherenkov telescope array consisting of four telescopes located in Namibia. Centaurus A has been observed for more than 120 h. A signal with a statistical(More)
Particle acceleration at supernova remnant (SNR) shock waves is regarded as the most probable mechanism for providing Galactic cosmic rays at energies below 10 15 eV. The Galactic cosmic ray hadron component would in this picture result from the injection of relativistic particles from many SNRs. It is well known that the superposition of individual power(More)