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Acceleration of petaelectronvolt protons in the Galactic Centre
(Nature Publishing Group, 2016)
Galactic cosmic rays reach energies of at least a few petaelectronvolts1 (of the order of 1015 electronvolts). This implies that our Galaxy contains petaelectronvolt accelerators (‘PeVatrons’), but all proposed models of ...
HESS upper limit on the very high energy γ-ray emission from the globular cluster 47 Tucanae
(EDP Sciences, 2009)
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) < 6.7 × 10−13 cm−2 ...
Discovery of very high energy y-ray emission from Centaurus A with HESS.
(IOP Publishing, 2009)
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 ...
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 ...