Related papers: Multi-messenger observations of thunderstorm-relat…
We present a survey of more than half a thousand thunderstorm ground enhancements, fluxes of electrons, and gamma rays associated with thunderstorms registered from 2008 to 2022 at Aragats space environmental center. We analyze correlations…
In 2023, a series of intense Thunderstorm Ground Enhancements (TGEs) were recorded on Mount Aragats in Armenia, with five events exceeding the fair-weather cosmic ray flux by more than 100 percent. This study comprehensively analyzes these…
We analyzed the structure of the Thunderstorm Ground Enhancement using a particle detector network on Aragats. We performed a statistical analysis of the particle flux enhancement time series on a nanosecond time scale using the largest TGE…
Thunderstorm Ground Enhancements (TGEs) are bursts of high-energy particle fluxes detected at Earth's surface, linked to the Relativistic Runaway Electron Avalanche (RREA) mechanism within thunderclouds. Accurate detection of TGEs is vital…
Aragats solar neutron telescope (ASNT) is a unique instrument allowing to measure the energy spectra of electrons accelerated and multiplied in the strong electric fields of the atmosphere. We describe the instrument setup, its operation…
During the multiyear monitoring of particle fluxes and near-surface electric field (NSEF) on the Aragats research station, no runway relativistic electron avalanches have been observed in the January-February months. The large peaks and…
Proceeding from a stormy day of 22 September 2022, when 7 thunderstorm ground enhancements occurred (TGEs, 3 of them very large), we perform an analysis of the most important conditions, on which depend the origination of the large particle…
The Pierre Auger Observatory has detected downward terrestrial gamma-ray flashes (TGFs) with its Surface Detector. A key to understanding this high-energy radiation in thunderstorms is to combine such measurements with measurements of…
During thunderstorms, the atmospheric electric field can increase above hundreds of kV/m, causing an acceleration in the charged particles of secondary cosmic rays. Such an acceleration causes avalanche processes in the atmosphere,…
Terrestrial Gamma ray Flashes (TGFs) -- very short, intense bursts of electrons, positrons, and energetic photons originating from terrestrial thunderstorms -- have been detected with satellite instruments. TETRA, an array of NaI(Tl)…
The Telescope Array (TA) of central Utah was designed to detect ultra-high-energy cosmic rays (UHECRs) and is the largest of its kind in the Northern hemisphere. Its capabilities, however, are not limited to extra-terrestrial sources.…
Terrestrial gamma ray flashes (TGFs) are very short bursts of gamma radiation associated to thunderstorm activity and are the manifestation of the highest-energy natural particle acceleration phenomena occurring on Earth. Photon energies up…
We report the observation results of the hard radiation flashes which accompanied the lightning discharges above the mountains of Northern Tien Shan. Time series of the counting rate intensity, numerical estimations of absolute flux, and…
Thunderstorms produce strong electric fields over regions on the order of kilometer. The corresponding electric potential differences are on the order of 100 MV. Secondary cosmic rays reaching these regions may be significantly accelerated…
The comparative analysis of three thunderstorms on Aragats in May 2021 demonstrates that relativistic runaway electron avalanches are developing in large areas of the thunderous atmosphere.
The H.E.S.S. Imaging Air Cherenkov Telescope system is very well suited to perform follow-up observations of detections at other wavelengths or messengers due to its fast reaction and its comparably low energy threshold. These advantages…
Various particle accelerators operate in the space plasmas, filling the Galaxy with high energy particles, primary cosmic rays. Reaching the atmosphere of the earth, these particles originate extensive air showers consisting of millions of…
Terrestrial gamma-ray flashes (TGFs) are short intense flashes of gamma rays associated with lightning activity in thunderstorms. Using Monte Carlo simulations of the relativistic runaway electron avalanche (RREA) process, theoretical…
Downward Terrestrial Gamma-ray Flashes (TGFs) are sub-millisecond bursts of MeV gamma rays produced in thunderclouds. According to the Relativistic Runaway Electron Avalanche model, gamma rays are produced, via bremsstrahlung, from electron…
Ultra-high-energy (E$>$100 Tev) Extensive Air Showers (EASs) have been monitored for a period of five years (1997 - 2003), using a small array of scintillator detectors in Tehran, Iran. The data have been analyzed to take in to account of…