Related papers: Electron Acceleration Mechanisms in Thunderstorms
We calculate numerically the radiation spectrum from relativistic electrons moving in small scale turbulent magnetic fields expected in high energy astrophysical sources. Such radiation spectrum is characterized by the strength parameter $a…
The origin and acceleration of high-energy particles in space (cosmic rays), constitute important topics in modern astrophysics. Among the The origin and acceleration of high-energy particles, constituting cosmic rays, is likely to remain…
In addition to a fast electromagnetic pulse (EMP), a high altitude nuclear burst produces a relatively slow magnetohydrodynarnic EMP (MHD EMP), whose effects are like those from solar storm geomagnetically induced currents (SS GIC). The MHD…
The origin of the highest energy cosmic rays is still unknown. The discovery of their sources will reveal the workings of the most energetic astrophysical accelerators in the universe. Current observations show a spectrum consistent with an…
Gamma-ray bursts are flashes of high-energy radiation lasting from a fraction of a second to several hours. Military satellites made the first detections of GRBs in the late 1960s. The $\gamma$-ray emission forms from shocks in a…
Cosmic rays reaching the atmosphere of an astrophysical object produce showers of secondary particles that may then escape into space. Here we obtain the flux of gamma rays and neutrinos of energy $E>10$ GeV emitted by the Sun, Jupiter and…
In the cosmological blast-wave model for gamma ray bursts (GRBs), high energy (> 10 GeV) gamma-rays are produced either through Compton scattering of soft photons by ultrarelativistic electrons, or as a consequence of the acceleration of…
The Milagro gamma-ray observatory employs a water Cherenkov detector to observe extensive air showers produced by high energy particles interacting in the Earth's atmosphere. Milagro has a wide field of view and high duty cycle, monitoring…
The generation of narrow beams of high-energy positrons (electrons) in the process of resonant photogeneration of ultrarelativistic electron-positron pairs by high-energy gamma quanta in the field of the nucleus and a strong electromagnetic…
High-energy photons are a powerful probe for astrophysics and for fundamental physics in extreme conditions. During the recent years, our knowledge of the most violent phenomena in the Universe has impressively progressed thanks to the…
Gamma-Ray Bursts (GRBs) are expected to efficiently accelerate protons up to relativistic energies. High-energy photons can originate from decay of neutral pions produced by the interaction of these protons with the medium surrounding the…
We propose that the strong millisecond extragalactic radio burst (mERB) discovered by Lorimer et al. (2007) may be related to a hyperflare from an extragalactic soft gamma-ray repeater. The expected rate of such hyperflares, $\sim$ 20 - 100…
The Large High Altitude Air Shower Observatory (LHAASO) has three sub-arrays, KM2A, WCDA and WFCTA. The flux variations of cosmic ray air showers were studied by analyzing the KM2A data during the thunderstorm on 10 June 2021. The number of…
A physical model of the formation of a vortex current in a plasma channel of lightning discharges due to the anomalous Hall effect caused by relativistic spin-orbit interaction phenomenon is proposed. The existence of fast electromagnetic…
High-energy photons are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the most violent phenomena in the Universe has impressively progressed thanks to the…
Massive protostars have associated bipolar outflows with velocities of hundreds of km s$^{-1}$. Such outflows can produce strong shocks when interact with the ambient medium leading to regions of non-thermal radio emission. We aim at…
Interactions of grazing incidence, ultra high energy cosmic rays with the earth's atmosphere may provide a new method of studying energetic cosmic rays with gamma-ray satellites. It is found that these cosmic ray interactions may produce…
The GRAPES-3 muon telescope located in Ooty, India records rapid ($\sim$10 min) variations in the muon intensity during major thunderstorms. Out of a total of 184 thunderstorms recorded during the interval April 2011-December 2014, the one…
A theory is proposed to explain with simplicity the basic observed properties of a Gamma Ray Burst (GRB). It employs a well-known result of Schwinger, that static electric fields in excess of a critical value are unstable to pair creation,…
We present the facilities of the Aragats Space Environmental Center in Armenia used during multi-year observations of the thunderstorm ground enhancements (TGEs) and corresponding environmental parameters. We analyze the characteristics of…