Related papers: Gamma-ray absorption in massive X-ray binaries
HESS J0632+057 is one of only two unidentified very-high-energy gamma-ray sources which appear to be point-like within experimental resolution. It is possibly associated with the massive Be star MWC 148 and has been suggested to resemble…
The recent detections of TeV gamma-rays from compact binary systems show that relativistic outflows (jets or winds) are sites of effective acceleration of particles up to multi-TeV energies. In this paper, we discuss the conditions of…
Blazars with redshifts z<0.1 are likely candidates for detection at energies in the range 300 GeV - 50 TeV with Cerenkov telescopes and scintillator arrays. We present gamma-ray flux predictions for a sample of 15 nearby flat-spectrum radio…
LS 5039 and LSI +61 303 are unique amongst high-mass X-ray binaries (HMXB) for their spatially-resolved radio emission and their counterpart at >GeV gamma-ray energies, canonically attributed to non-thermal particles in an accretion-powered…
LS I +61 303 and LS 5039 are exceptionally rare examples of HMXBs with MeV-TeV emission, making them two of only five known or proposed "gamma-ray binaries". There has been disagreement within the literature over whether these systems are…
The X-ray binary LSI +61 303, consisting of a main sequence Be star and a compact object has been detected in the TeV range with MAGIC and VERITAS, and showed a clear intensity modulation as a function of the orbital phase. We describe a…
We report on detailed analysis of the hard X-ray and GeV gamma-ray spectra of LS 5039, one of the brightest gamma-ray binary system in the Galaxy. The NuSTAR observation covering its entire orbit in 2016 allowed us for the first time to…
The microquasar LS 5039 has recently been detected as a source of very high energy (VHE) $\gamma$-rays. This detection, that confirms the previously proposed association of LS 5039 with the EGRET source 3EG~J1824$-$1514, makes of LS 5039 a…
The Fermi Large Area Telescope (LAT) reported the first definitive GeV detections of the binaries LS I +61\degree 303 and LS 5039 in the first year after its launch in June, 2008. These detections were unambiguous as a consequence of the…
The population of high energy and very high energy gamma-ray sources, detected with EGRET and the new generation of ground-based Cherenkov telescopes, conforms a reduced but physically important sample. Most of these sources are…
The pair-production absorption of high-energy gamma-rays by intergalactic low-energy photons is expected to produce a high-energy cutoff in the spectra of extragalactic sources which is a sensitive function of redshift. We first discuss the…
The microquasar Cygnus X-3 was detected at high energies by the gamma-ray space telescopes AGILE and Fermi. The gamma-ray emission is transient, modulated with the orbital period and seems related to major radio flares, i.e. to the…
Cygnus X-1 and LS 5039 are two X-ray binaries observed at TeV energies. Both sources are compact systems, contain jet-like (radio) structures, and harbor very luminous O stars. A TeV signal has been found around the superior conjunction of…
We report the Fermi Large Area Telescope (Fermi-LAT) detection of the gamma-ray emission towards the young massive star cluster RSGC 1. Using the latest source catalog and diffuse background models, we found that the diffuse gamma-ray…
Gamma-ray binaries allow us to study physical processes such as particle acceleration up to TeV energies and VHE gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce outflows…
LS 5039 is one of the four TeV emitting X-ray binaries detected up to now. The powering source of its multi-wavelength emission can be accretion in a microquasar scenario or wind interaction in a young non-accreting pulsar scenario. These…
LS 5039 is one of the four TeV emitting X-ray binaries detected up to now. The powering source of its multi-wavelength emission can be accretion in a microquasar scenario or wind interaction in a young non-accreting pulsar scenario. These…
LS 5039 is among the most interesting VHE sources in the Galaxy. Two scenarios have been put forward to explain the observed TeV radiation: jets vs pulsar winds. The source has been detected during the superior conjunction of the compact…
We report on a 40ks Chandra observation of the TeV emitting high mass X-ray binary HESS J0632+057 performed in February 2011 during a high-state of X-ray and TeV activity. We have used the ACIS-S camera in Continuos Clocking mode to search…
We consider propagation of very high energy (VHE) gamma-rays in the radiation field of a massive star in the binary system Cen X-3, which has been reported as a source of gamma-ray photons in the GeV and TeV energies. VHE gamma-rays or…