A.V. Gurevich

Intensive X-ray emission bursts during thunderstorms

Abstract The intensive X-ray emission during thunderstorms was studied at a height of 3340 m above sea level. For the first time, short-time (1–5 min) bursts of X-ray emission were observed. The bursts are highly correlated over a wide space region (about 0.5 km). The main component of X-ray emission in bursts has energies between 50–80 keV. The observed bursts could be attributed to the bremsstrahlung determined by the runaway breakdown (RB) effect in the thunderclouds electric field. Ground-based observations of RB open a wide range of opportunities for the studies of fundamental processes in thunderstorms.

Experimental evidence of giant electron-gamma bursts generated by extensive atmospheric showers in thunderclouds

The existence of a new phenomena - giant electron-gamma bursts is established. The bursts are generated in thunderclouds as a result of the combined action of runaway breakdown and extensive atmosphere showers (RB-EAS). The experiments were fulfilled at the Tien Shan Mountain Scientific Station using EAS-Radio installation. This specially constructed installation consists of a wide spread EAS trigger array and a high time resolution radiointerferometer.

Effective growth of a number of cosmic ray electrons inside thundercloud

Abstract Significant enhancement of secondary cosmic ray electrons inside electrically charged clouds is established. The effect is observed in a quiet phase of thunderstorm—in the absence of lightning, rainfall and bursts of X-ray emission. The observations are fulfilled in Tien-Shan Mountains at the modernized thunderstorm–cosmic ray (TCR) installation [Phys. Lett. A 275 (2002) 90; J. Phys. G 28 (2) (2002) 251].

Generation of electron–positron pairs in runaway breakdown

Abstract The full kinetic theory of runaway breakdown for electrons at high energy range is developed. The theory takes into account both ionization and bremsstrahlung processes. The electron–positron pairs generation is studied. The possibility to observe e + e − annihilation line during intensive discharges in atmosphere is predicted.

The fluctuation spectrum cut-off in a neutralino dark matter scenario

Abstract An evolution of the density perturbation spectrum of neutralino cold dark matter in an expanding universe is investigated. Background neutralino scattering is taken into account. This scattering is shown to determine the development of the fluctuation spectrum for a long time after neutralino freezing out. A primordial fluctuation spectrum cut-off and the mass of minimal objects are determined.

Self-focusing instability of plasma waves excited by powerful HF radiation

Abstract The possibility to create small scale plasma density fluctuations at the initial stage of ionospheric modification by powerful HF radio waves is discussed. The thermal self-focusing instability of plasma waves excited in the reflection region of the pump is considered as a main source of striations. Ponderomotive effects are also taken into account resulting in a decrease of the scales of the instability orthogonal to the magnetic field and a strong increase of the growth rate. Striations produced by the self-focusing instability can be a source of initial fluctuations at the upper hybrid resonance level of the pump necessary to striation development at further stages of the ionospheric modification.

The influence of dark matter on the motion of planets and satellites in the solar system

Abstract Two effects of the influence of dark matter on planets and satellites are predicted and analyzed. If the existing accuracy of planet tracking will be improved by only several times then one of these effects may be observed.

Cosmic rays and thunderstorms at the Tien-Shan mountain station

Experimental work of the past few years has shown that runaway breakdown determines the maximum electric field strength in thunderclouds and is behind a variety of phenomena newly observed in thunderstorm atmosphere, such as TGFs, TLEs, etc. The necessary condition for the occurrence of runaway avalanche is the existence of high-energy electrons. In the atmosphere, these are the cosmic ray secondary electrons. Therefore the observed effects reflect close relationship between cosmic rays and electrodynamic processes in a thunderstorm atmosphere. The Tien-Shan high-altitude cosmic ray station is a unique site for investigations effects of cosmic rays and thunderstorm discharge. Thunderstorm detector complex is designed especially for a systematical study of atmospheric discharges by the means of simultaneous recording of the different kinds of radiation. The presence of a widespread extensive air shower trigger set-up at the Tien-Shan station permits to study the role of energetic cosmic ray particles in lightning development. Overview of main results, obtain during last several years at the Tien-Shan are presented. A phenomenological description and theoretical vision of the cosmic rays role in atmosphere processes during thunderstorm are discussed.

Local anisotropy of gamma-bursts' angular distribution

Abstract Using COMPTON observatory data, we have found the existence of the local cluster of gamma-ray sources in the region of the celestial sphere corresponding to the halo of Andromeda (galaxy M31). It is in agreement with the giant dark matter halo (GDMH) model.

Generation of low-frequency emission by powerful HF radio waves in the earth's ionosphere

Abstract We discuss artificial low-frequency emission generated via a decay process during the heating of the ionosphere by HF electromagnetic waves. The spectral characteristics of the emission and its intensity are found.