Related papers: Gamma Hadron Separation using Pairwise Compactness…
In atmospheric \v{C}erenkov technique $\gamma-$rays are detected against abundant background produced by hadronic showers. In order to improve signal to noise ratio of the experiment, it is necessary to reject a significant fraction of…
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…
This work is a methodical study of another option of the hybrid method originally aimed at gamma/hadron separation in the TAIGA experiment. In the present paper this technique was performed to distinguish between different mass groups of…
Identification of primary cosmic rays on an event-by-event basis is a much-desired capability of cosmic-ray observatories. Several cosmic-ray air-shower experiments use so-called photon tags for gamma hadron primary particle discrimination.…
The observation of very-high-energy (VHE, E>100 GeV) gamma rays is mediated by the imaging atmospheric Cherenkov technique (IACTs). At these energies, gamma rays interact with the atmosphere to create a cascade of electromagnetic air…
The discovery of ultra-high energy gamma-ray sources (detected at energies $\geq$ 100 TeV) thanks to highly sensitive observatories such as the High Altitude Water Cherenkov (HAWC) Observatory, the Tibet AS-gamma Experiment, and the Large…
The High Altitude Water Cherenkov (HAWC) high-energy {\gamma}-ray observatory was completed in march 2015 in central Mexico. The detector, consisting of 300 water tanks, is currently being upgraded to improve its performance at Multi-TeV…
This work is a methodical study on hybrid reconstruction techniques for hybrid imaging/timing Cherenkov observations. This type of hybrid array is to be realized at the gamma-observatory TAIGA intended for very high energy gamma-ray…
We present a new methodology to discriminate between light and heavy ultra-high energy cosmic-ray primaries on an event-by-event basis using information from the radio detection of extensive air showers at MHz frequencies. Similarly to…
The identification of gamma-ray induced air showers with Cherenkov telescopes suffers from contamination with a specific class of cosmic ray induced air showers. The predictions for this background show strong discrepancies between the…
Cherenkov images of air showers can also be classified using multifractal and wavelet parameters, as compared to the conventional Hillas image parameters. This technique was applied to the images recorded by the cameras of the stereoscopic…
Very High Energy (VHE) gamma rays and charged cosmic rays (CCRs) provide an observational window into the acceleration mechanisms of extreme astrophysical environments. One of the major challenges at Imaging Air Cherenkov Telescopes (IACTs)…
Microquasars with high-mass companion stars are promising very-high-energy (VHE; 0.1-100 TeV) gamma-ray emitters, but their behaviors above 10 TeV are poorly known. Using the High Altitude Water Cherenkov (HAWC) observatory, we search for…
While the fluorescence and the ground counter techniques for the detection of ultra-high energy cosmic rays (UHECR) were being developed for decades, the interest in the radio detection diminished after the initial experiments in the 1960s.…
High Energy Cosmic Rays (C.R.) versus Neutrino and Neutralino induced Air-Shower maybe tested at Horizons by their muons, gamma and Cerenkov blazing signals. Inclined and Horizontal C.R. Showers (70-90 zenith angle) produce secondary…
We study the propagation of Cerenkov photons generated by Very High Energy gamma-rays and hadrons in the atmosphere. The photon production height distributions are estimated from semi-empirical methods and compared with those derived by…
We investigate a possible new technique for microwave measurements of ultra-high energy cosmic ray (UHECR) extensive air showers which relies on detection of expected continuum radiation in the microwave range, caused by free-electron…
GAW (Gamma Air Watch) is a pathfinder experiment in the TeV range to test the feasibility of a new generation of Imaging Atmospheric Cherenkov Telescopes (IACT). It combines high flux sensitivity with large field-of-view (FoV=24deg x 24deg)…
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is a wide field-of-view observatory sensitive to 100 GeV - 100 TeV gamma rays and cosmic rays. The HAWC observatory is also sensitive to diverse indirect searches for dark…
With an instantaneous field of view of 2 sr and a duty cycle > 95%, the High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory is a perfect instrument for monitoring variable TeV sources. Because radio galaxies are a type of Active…