相关论文: Robust constraints on Lorentz Invariance Violation…
VERITAS, an array of atmospheric-Cherenkov telescopes sensitive to gamma rays in the very-high-energy range (VHE, E > 100 GeV), carries out an extensive multimessenger program focused on the search for electromagnetic counterparts to…
One of the main purposes in $\gamma$-ray astronomy is linked to the origin of Galactic cosmic rays. Unlike cosmic rays, $\gamma$ rays can be used to probe their production sites in the Galaxy and to find which type of astrophysical sources…
Lorentz invariance violation (LIV) can manifest itself by an energy-dependent vacuum dispersion of light, which leads to arrival-time differences of photons with different energies originating from the same astronomical source. The spectral…
We discuss the effect of hypothetical violation of Lorentz invariance at high energies on the formation of atmospheric showers by very-high-energy gamma rays. In the scenario where Lorentz invariance violation leads to a decrease of the…
Geminga is a nearby (250 pc) middle-aged (spin-down time scale ~12,000 years) pulsar associated with a supernova remnant. Geminga has been a prime candidate for the origin of the unexpectedly high flux of cosmic-ray positrons above 10 GeV…
Radio galaxies host relativistic jets oriented away from our line of sight, making them challenging targets for Very High Energy (VHE, E$>$100 GeV) $\gamma$-ray detectors. Indeed, out of $\sim100$ extragalactic sources detected at $E>100$…
We report on observations of the nova-like cataclysmic variable AE Aqr performed by MAGIC. The observations were part of a quasi-simultaneous multi-wavelength campaign carried out between 2012 May and June covering the optical, UV, X-ray…
Recent observations with atmospheric Cherenkov telescope systems such as H.E.S.S. and MAGIC have revealed a large number of new sources of very-high-energy (VHE) gamma-rays from 100 GeV - 100 TeV, mostly concentrated along the Galactic…
The VERITAS collaboration has approved long-term observations on several distant, hard-spectrum blazars. We present first results from VERITAS long-term observations of 1ES1218+304, 1ES0229+200, and 1ES0414+009. Gamma-ray observations of…
Observations of high energy neutrinos, both in the laboratory and from cosmic sources, can be a useful probe in searching for new physics. Such observations can provide sensitive tests of Lorentz invariance violation (LIV), which may be a…
An anomalously large transparency of the Universe to gamma rays has recently been discovered by the Imaging Atmospheric Cherenkov Telescopes (IACTs) H.E.S.S. and MAGIC. We show that observations can be reconciled with standard blazar…
Lorentz invariance violations (LIV) can yield vacuum birefringence, which results in an energy-dependent rotation of the polarization vector of linearly polarized emission from astrophysical sources. It is believed that if the relative…
Very high energy gamma-ray observations offer indirect methods for studying the highest energy cosmic rays in our Universe. The origin of cosmic rays at energies greater than $10^{18}$ eV remains a mystery, and many questions in particle…
The recent discovery of TeV emission from gamma-ray bursts (GRBs) by the MAGIC and H.E.S.S. Cherenkov telescopes confirmed that emission from these transients can extend to very high energies. The TeV energy domain reaches the most…
The fast repositioning system of the MAGIC Telescope has allowed during its first data cycle, between 2005 and the beginning of year 2006, observing nine different GRBs as possible sources of very high energy gammas. These observations were…
Data obtained in the very high energy gamma-ray band with the new generation of imaging telescopes, in particular through the galactic plane survey undertaken by H.E.S.S., low threshold observations with MAGIC and more recently by operation…
Studying gamma-ray emission by Galactic objects is key to understanding the origins and acceleration mechanisms of Galactic cosmic ray electrons and hadrons. The HAWC observatory provides an unprecedented view of the gamma-ray sky at TeV…
The VERITAS observatory, located in southern Arizona, is engaged in an exploration of the gamma-ray sky at energies above 85 GeV. Observations of Galactic and extragalactic sources in the TeV band provide clues to the highly energetic…
Recently, the HESS collaboration has reported the detection of gamma-ray emission above a few hundred GeV from eight new sources located close to the Galactic Plane. The source HESS J1813-178 has sparked particular interest, as subsequent…
The launch of the Fermi gamma-ray space telescope and the imaging air Cerenkov telescopes H.E.S.S., MAGIC, and VERITAS have substantially transformed our knowledge of gamma-ray sources in the last decade. The extragalactic gamma-ray sky is…