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Predictions of gamma-ray emission from globular cluster millisecond pulsars above 100 MeV
(IOP Publishing, 2009)
The recent Fermi detection of the globular cluster (GC) 47 Tucanae highlighted the importance of modeling
collective gamma-ray emission of millisecond pulsars (MSPs) in GCs. Steady flux from such populations is also
expected ...
HESS very-high-energy gamma-ray sources without identified counterparts
(EDP sciences, 2008)
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV–100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical sources. For this ...
Radio imaging of the very-high-energy y-ray emission region in the central engine of a radio galaxy
(Science AAAS, 2009)
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 ...
Simultaneous HESS and Chandra observations of Sagitarius A* during an X-ray flare
(EDP Sciences, 2008)
The rapidly varying (~10 min timescale) non-thermal X-ray emission observed from Sgr A implies that particle acceleration is occuring close to the event horizon of the supermassive black hole. The TeV γ-ray source ...
Simultaneous multiwavelength observations of the second exceptional y-ray flare of PKS 2155-304 in July 2006
(EDP Sciences, 2009)
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. ...
HESS observations of y-ray bursts in 2003-2007
(EDP Sciences, 2009)
Aims. Very-high-energy (VHE; $\ga$100 GeV) $\gamma $-rays are expected from $\gamma $-ray bursts (GRBs) in some scenarios. Exploring this photon energy regime is necessary for understanding the energetics and properties ...
Discovery of extended VHE Y-ray emission from the vicinity of the young massive stellar cluster Westerlund 1
(EDP Sciences, 2012)
Aims. Results obtained in very-high-energy (VHE; E≥100GeV) γ-ray observations performed with the H.E.S.S. telescope array are used to investigate particle acceleration processes in the vicinity of the young massive stellar ...
Discovery of VHE emission towards the Carina arm region with the H.E.S.S. telescope array: HESS J1018-589
(EDP Sciences, 2012)
The Carina arm region, containing the supernova remnant SNR G284.3–1.8, the high-energy (HE; E > 100 MeV) binary 1FGL J1018.6–5856 and the energetic pulsar PSR J1016–5857 and its nebula, has been observed with the H.E.S.S. ...
Discovery of gamma-ray emission from the extragalactic pulsar wind nebula N 157B with H.E.S.S
(EDP Sciences, 2012)
We present the significant detection of the first extragalactic pulsar wind nebula (PWN) detected in gamma rays, N 157B, located in the large Magellanic Cloud (LMC). Pulsars with high spin-down luminosity are found to power ...
The 2010 very high energy γ-ray flare and 10 years of multi-wavelength observations of M 87
(IOP Publishing, 2012)
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 – 6) × 109 M☉) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) γ-ray ...