ИСТИНА

A number of experiments with scintillator gamma-spectrometers were provided by SINP MSU for study of spectral, temporal and spatial characteristics of TGEs as well as for search of fast hard x-ray and gamma-ray flashes probably appearing at the moment of lightning. The measurements were done in Moscow region and in Armenia at Aragatz mountain. Each instrument used in this work was able to record data in so called “event mode”: the time of each interaction was recorded with ~15 mcs accuracy together with detailed spectral data. Such design allowed one to look for fast sequences of gamma-quanta, coming at the moments of discharges during thunderstorms. The pulse-shape analysis made by detector electronics was used to separate real gamma-ray events and possible imitations of flashes by electrical disturbances when discharges occur. The moment of external trigger signal coming from UV/optical flash detector or from radio-frequency analyzer can be recorded and used for multiwavelength analysis. During the time period from spring to autumn of 2015 a number of TGEs were detected. Spectral analysis of received data showed that the energy spectrum of coming radiation in 20-3000 kev range is similar to the background one and does not contain gamma-ray lines. In order to measure the direction from which the additional gammas come the experiment with collimated gamma-spectrometer placed on rotated platform was done. The results of this experiment realized in Moscow region from 2015, august will be presented as well as the results of comparison of different TGEs measured in Moscow region and in Armenia.