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Morphologically it appears as if the Vela X PWN consists of two emission regions: whereas X-ray (1 keV) and very high energy (VHE) H.E.S.S. gamma-ray observations appear to define a cocoon type shape south of the pulsar, radio observations reveal an extended area of size 2 deg by 3 deg (including the cocoon area), also south of the Vela pulsar. Since no wide field of view (FoV) observations of the synchrotron emission between radio and X-rays are available, we do not know how the lepton (e+/-) spectra of these two components connect and how the morphology changes with energy. Currently we find that two distinct lepton spectra describe the respective radio and X-ray/VHE gamma-ray spectra, with a field strength of 5 muG self-consistently describing a radiation spectral break (or energy maximum) in the multi-TeV domain as observed by H.E.S.S. (if interpreted as IC radiation), while predicting the total hard X-ray flux above 20 keV (measured by the wide FoV INTEGRAL instrument) within a factor of two. If this same field strength is also representative of the radio structure (including filaments), the implied IC component corresponding to the highest radio frequencies should reveal a relatively bright high energy gamma-ray structure and Fermi LAT should be able to resolve it. A higher field strength in the filaments would however imply fewer leptons in Vela X and hence a fainter Fermi LAT signal.
Previous observations with HESS have revealed the existence of an extended very-high-energy (VHE; E>100 GeV) gamma-ray source, HESS J1834-087, coincident with the SNR W41. The origin of the gamma-ray emission has been further investigated with HESS a
Vela X is a region of extended radio emission in the western part of the Vela constellation: one of the nearest pulsar wind nebulae (PWNe), and associated with the energetic Vela pulsar (PSR B0833-45). Extended very-high-energy (VHE) $gamma$-ray emis
The Large Area Telescope (LAT) on Fermi has detected ~150 gamma-ray pulsars, about a third of which were discovered in blind searches of the $gamma$-ray data. Because the angular resolution of the LAT is relatively poor and blind searches for pulsars
The most spectacular aspect of cluster radio emission is represented by the large-scale diffuse radio sources, which cannot be obviously associated with any individual galaxy. These sources demonstrate the existence of relativistic particles and magn
Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV-100 TeV) $gamma$-ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a faint VHE $gamma$-ray emitter, though its VHE flux exceeds both the