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Discovery of very high energy gamma-ray emission coincident with molecular clouds in the W 28 (G6.4-0.1) field
(EDP Sciences, 2008)
Aims. Observations of shell-type supernova remnants (SNRs) in the GeV to multi-TeV γ-ray band, coupled with those at millimetre radio
wavelengths, are motivated by the search for cosmic-ray accelerators in our Galaxy. The ...
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 ...