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Upper limits from HESS active galactic nuclei observations in 2005-2007
(EDP Sciences, 2008)
Aims.Very high energy (VHE; GeV) γ-ray studies were performed for 18 active galactic nuclei (AGN) from a variety of AGN classes.
Methods.VHE observations of a sample of 14 AGN, considered candidate VHE emitters, were ...
Discovery of VHE gamma-rays from the high-frequency-peaked BL Lacertae object RGB J0152+017
(EDP Sciences, 2008)
Aims. The BL Lac object RGB J0152+017 (z=0.080) was predicted to be a very high-energy (VHE; >100 GeV) $\gamma$-ray source, due to its high X-ray and radio fluxes. Our aim is to understand the radiative processes by ...
Discovery of VHE y-rays from the BL Lacertae object PKS 0548-322
(EDP Sciences, 2010)
Aims. PKS 0548-322 (z=0.069) is a "high-frequency-peaked'' BL Lac object and a candidate very high energy (VHE, E >100 GeV) $\gamma$-ray emitter, due to its high X-ray and radio flux. Observations at the VHE band provide ...
Observations of the Sagitarrius dwarf galaxy by the HESS experiment and search for a dark matter signal
(Elsevier, 2008)
Observations of the Sagittarius dwarf spheroidal (Sgr dSph) galaxy were carried out with the HESS array of four imaging air Cherenkov telescopes in June 2006. A total of 11 h of high quality data are available after data ...
Exploring a SNR/molecular cloud association within HESS J1745-303
(EDP Sciences, 2008)
Aims. HESS J1745−303 is an extended, unidentified VHE (very high energy) gamma-ray source discovered using HESS in the Galactic Plane
Survey. Since no obvious counterpart has previously been found in longer-wavelength ...
HESS upper limits for Kepler's supernova remnant
(EDP sciences, 2008)
Aims. Observations of Kepler's supernova remnant (G4.5+6.8) with the HESS telescope array in 2004 and 2005 with a total live time of 13 h are presented. Methods. Stereoscopic imaging of Cherenkov radiation from extensive ...
Multi-wavelength observations of H 2356-309
(EDP Sciences, 2010)
Aims. The properties of the broad-band emission from the high-frequency peaked BL Lac H 2356–309 (z = 0.165) are investigated.
Methods. Very high energy (VHE; E > 100 GeV) observations of H 2356–309 were performed with ...
A multiwavelength view of the flaring state of PKS 2155-304 in 2006
(EDP Sciences, 2012)
Context: Multiwavelength (MWL) observations of the blazar PKS 2155-304 during two weeks in July and August 2006, the period when two exceptional flares at very high energies (VHE, E ≳ 100 GeV) occurred, provide a detailed ...
Search for Lorentz invariance breaking with a likelihood fit of the PKS 2155-304 flare data taken on MJD 53944
(Elsevier, 2011)
Several models of Quantum Gravity predict Lorentz Symmetry breaking at energy scales approaching the Planck scale (∼1019 GeV). With present photon data from the observations of distant astrophysical sources, it is possible ...
H.E.S.S. constraints on dark matter annihilations towards the Sculptor and Carina dwarf galaxies
(Elsevier, 2011)
The Sculptor and Carina dwarf spheroidal galaxies were observed with the H.E.S.S. Cherenkov telescope array between January 2008 and December 2009. The data sets consist of a total of 11.8 h and 14.8 h of high quality data, ...