Related papers: VHE gamma-rays from Westerlund 2 and implications …
The high and very-high energy spectrum of gamma-ray binaries has become a challenge for all theoretical explanations since the detection of powerful, persistent GeV emission from LS 5039 and LS I +61 303 by Fermi/LAT. The spectral cutoff at…
Different theoretical models predict VHE gamma-ray emission to arise in tight binary star systems (high mass-loss and high wind speeds), which has not been confirmed experimentally so far. Here we present the first bounds on the VHE…
The discovery of non-thermal X-ray emission from the jets of some X-ray binaries, and especially the discovery of GeV-TeV gamma-rays in some of them, provide a clear evidence of very efficient acceleration of particles to multi-TeV energies…
The dense wind environment (or circumstellar medium) may be ubiquitous for the regular Type II supernovae (SNe) before the explosion, the interaction of which with the SN ejecta could result in a wind breakout event. The shock generated by…
Gamma-ray binaries are systems containing a massive star and a compact object that have been detected up to TeV energies. The high energy emission could result from particle acceleration in the region where the stellar wind from the massive…
The discovery of extended TeV emission around the Geminga and PSR B0656+14 pulsars, with properties consistent with free particle propagation in the interstellar medium (ISM), has sparked considerable discussion on the possible presence of…
The HAWC Gamma-Ray Observatory has reported the discovery of TeV gamma-ray emission extending several degrees around the positions of Geminga and B0656+14 pulsars. Assuming these gamma rays are produced by inverse Compton scattering off…
We report on the latest discovery of an extended Very High Energy (VHE) gamma-ray source near the 67 ms pulsar PSR J1831-0952 during the H.E.S.S. Galactic Plane Survey (GPS). The dispersion measure distance of the pulsar (4.3 kpc) would…
TeV haloes are a recently discovered class of very high energy gamma-ray emitters. These sources consist of extended regions of multi-TeV emission, originally observed around the two well-known and nearby pulsars, Geminga and PSR B0656+14…
Many of the recently discovered TeV gamma-ray sources are associated with pulsar wind nebulae (PWNe). In fact, they represent the most populous class of Galactic sources at TeV energies. In addition, HESS has also discovered, in a survey of…
The extended TeV gamma-ray source HESS J1023-575 is coincident with the massive, young stellar cluster Westerlund 2 (Wd2) and its surrounding HII region RCW 49. On the basis of an analysis of the CO emission and 21 cm absorption along the…
We present a detailed study of the gamma-ray emission from the direction of the star-forming region W30 based on a decade of the Fermi Large Area Telescope data in the 0.3-300 GeV photon energy range. The morphological and spectral analyses…
Gamma-ray loud X-ray binaries are binary systems that show non-thermal broadband emission from radio to gamma rays. If the system comprises a massive star and a young non-accreting pulsar, their winds will collide producing broadband…
(abridged) Gamma-ray binaries are massive stars with compact object companions that are observed to emit most of their energy in the gamma-ray range. One of these binaries is known to contain a radio pulsar, PSR B1259-63. Synchrotron and…
The H.E.S.S. (High Energy Stereoscopic System) telescopes observed Coma for ~8hr in a search for gamma-ray emission at energies >1TeV. The large 3.5deg FWHM field of view of H.E.S.S. is ideal for viewing a range of targets at various sizes…
Particle acceleration in clusters of galaxies is expected to take place at both merger and accretion shocks. The electron component may be energized to energies of several TeV, and upscatter a small fraction of the photons in the cosmic…
Photons with very high energy up to TeV (VHE) emitted from active galactic nuclei (AGNs) provide some invaluable information of the origin of $\gam$-ray emission. Although 66 blazars have been detected by {\it EGRET}, only three low…
Star clusters larger than $\sim 10^{3}$ $M_\odot$ contain multiple hot stars that launch fast stellar winds. The integrated kinetic energy carried by these winds is comparable to that delivered by supernova explosions, suggesting that at…
Recent observations of binary systems obtained with the H.E.S.S. telescopes are providing crucial information on the physics of relativistic outflows and the engines powering them. We report here on new H.E.S.S. results on HESS J0632+057,…
Recent reports claiming tentative association of the massive star binary system gamma^2 Velorum (WR 11) with a high-energy gamma-ray source observed by Fermi-LAT contrast the so-far exclusive role of Eta Carinae as the hitherto only…