Related papers: A model for the two component gamma-ray spectra ob…
We report the first detection of gamma-ray emission up to ultra-high-energy (UHE; $>$100 TeV) emission from the prototypical gamma-ray binary system LS I +61 303 using data from the Large High Altitude Air Shower Observatory (LHAASO). It is…
Ultrahigh energy protons and nuclei from extragalactic cosmic ray sources initiate intergalactic electromagnetic cascades, resulting in observable fluxes of $\gamma$-rays in the GeV-TeV energy domain. The total spectrum of such cascade…
We report on the presence of very rapid hard X-ray variability in the $\gamma$-ray binary LS I +61 303. The results were obtained by analysing NuSTAR data, which show two achromatic strong flares on ks time-scales before apastron. The…
Observations of high energy gamma rays recently revealed a persistent source in spatial coincidence with the binary system Eta Carinae. Since modulation of the observed gamma-ray flux on orbital time scales has not been reported so far, an…
Non-thermal variable emission from radio to very-high energy gamma rays (VHE; >100 GeV) are the prime characteristics of gamma-ray binaries. The underlying physical processes leading to the observed VHE emission are not well understood, as…
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…
Current generation of ground based gamma-ray telescopes observed dozens of sources of photons above 100 TeV. Supernova remnants, pulsar wind nebulae, young stellar clusters and superbubbles are considered as possible sites of PeV-regime…
The recently discovered soft gamma-ray emission from the anomalous X-ray pulsar 1E 1841-045 has a luminosity L_g ~ 10^{36} ergs/s. This luminosity exceeds the spindown power by three orders of magnitude and must be fed by an alternative…
We study the gamma-ray emissions from an outer-magnetospheric potential gap around a rotating neutron star. Migratory electrons and positrons are accelerated by the electric field in the gap to radiate copious gamma-rays via curvature…
Observations of the PSR B1259-63/SS2883 binary system using the CANGAROO-II Cherenkov telescope are reported. This nearby binary consists of a 48msec radio pulsar in a highly eccentric orbit around a Be star, and offers a unique laboratory…
Recently, AMS-02 reported their observed results of cosmic rays(CRs). In addition to the AMS-02 data, we add HESS data to estimate the spectra of CR electrons and the diffuse gamma rays above TeV. In the conventional diffusion model, a…
LS I +61 303 has been recently detected as a periodic gamma-ray source by the Major Atmospheric Imaging Cerenkov (MAGIC) telescope. A distinctive orbital correlation of the $\gamma$-ray emission was found. This work shows that the range of…
The high-energy radiation from short period binaries containing a massive star with a compact relativistic companion was detected from radio to TeV gamma rays. We show here that PeV regime protons can be efficiently accelerated in the…
We present a hadronic model of activity for Galactic gamma-ray-loud binaries, in which the multi-TeV neutrino flux from the source can be much higher and/or harder than the detected TeV gamma-ray flux. This is related to the fact that most…
With the arrival of powerful, ground-based gamma-ray detectors, we can now begin to seriously probe, via simultaneous X-ray/TeV observations, the origin of the gamma-ray emission in the blazars Mrk 421 and 501. If the synchrotron-Compton…
LS I +61 303 is one of the most studied X-ray binary systems because of its two peculiarities: On the one hand being the probable counterpart of the variable gamma ray source 2CG 135+01 (Gregory and Taylor 1978; Tavani et al. 1998) and on…
The bulk of the cosmic rays up to about 100 TeV are thought to be accelerated by the 1st order Fermi mechanism at supernova shocks, producing a power-law spectrum. Both electrons and protons should be accelerated, but their ratio on…
The AMS-02 experiment has reported precise measurements of energy spectra of several cosmic-ray species in the range of ~(0.5-2000) GeV/n. An intriguing finding is the differences in the spectral shape between the different species. Protons…
A long standing problem in high energy astrophysics is the nature of galactic accelerators of particles with energies above PeV. Such objects are sources of galactic cosmic rays and can produce PeV-regime photons observed by ground-based…
In gamma-ray binaries such as LS 5039 a large number of electron-positron pairs are created by the annihilation of primary very high energy (VHE) gamma-rays with photons from the massive star. The radiation from these particles contributes…