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Information × Registration Number 0218U006199, 0116U005172 , R & D reports Title Fundamental studies of the interaction of ultra electrons with the crystal, nuclear physics research in the beams polarized light and studying the possibility of high-tech physical experiment for nuclear power and nuclear medicine popup.stage_title Head Maslov Mykola Ivanovich, Кандидат фізико-математичних наук Registration Date 28-03-2018 Organization National Science Center "Kharkiv Institute of Physics and Technology popup.description2 The aim of this work is to study coherent radiation generated by electrons with an energy of 150-200 MeV in diamond crystals in the transition region from the KGV to the radiation during channeling. The method of investigation is theoretical-experimental. Systematic studies of gamma-ray spectra generated by electrons with an energy of E0 = 192.7 MeV in 100-m-thick diamond crystals in the transition region from coherent bremsstrahlung to radiation in channeling were carried out at the MAX lab unit in Lund, Sweden. The obtained gamma-ray spectra of electrons for axial, area and out-of-plane orientation over a wide range of angles of electrons entering the crystal with respect to the <100> axis. Similar experimental studies at electron energies E0 ~ 200 MeV have not been carried out previously. The spectrum of the gamma-radiation intensity of electrons under axial orientation was first obtained, which is shown by an increase in the intensity of radiation of photons with energy Eg ~ 1 MeV by a factor of ~ 16 above the radiation intensity in an amorphous medium. The theoretical model developed at the NSC KIPT, based on the simulation of the motion of electrons and their radiation in a crystal, is tested in the quasi-classical approximation of QED. The model correctly reflects the dynamics of electrons in the crystal and the main characteristics of radiation processes, and well describes the experimental results. This makes it possible to use it to analyze the mechanisms of electron emission in crystals. Thus, the mechanisms of emission of electrons with a given energy in a diamond crystal 100 mkm thick were investigated. It is determined that the main contribution to the intensity of gamma radiation under axial orientation is due to electrons moving in the above-barrier stochastic regime at small angles to the crystal axis <100>, ~ ax. With an increase in the angles of electrons entering the crystal relative to the axis to 10 Ax, the motion of the electrons becomes practically rectilinear and the main contribution to the gamma radiation intensity is due to radiation interference caused by periodic collisions of electrons or crystal chains located in crystalline planes, collisions of an electron with crystalline planes. Product Description popup.authors Бочек Георгій Леонідович Бурдейний Дмитро Дмитрович Васильєв Геннадій Петрович Ганенко Володимир Борисович Деєв Олексій Степанович Дубіна Володимир Николаевич Кіпріч Сергій Костянтинович Каплій Олександр Андрійович Маслов Микола Іванович Овчинник Володимир Дмитрович Потін Сергій Михайлович Шуліка Максим Юрійович Яловенко Володимир Іванович popup.nrat_date 2020-04-02 Close