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The paper describes a study of a new relativistic microwave Cherenkov generator of millimeter wavelength range with the transverse dimension of the electrodynamic system D>2.5λ, where D is the average diameter of the slow wave structure, and λ is the radiation wavelength. The investigations were carried out with a high-current SINUS-200 electron accelerator at a voltage of 473 kV and an electron beam current of 3.8 kA. The use of several, complementing each other, mechanisms of suppression of parasitic waves provides stable microwave generation at a specified frequency of 36.4 GHz. The microwave power in the experiment 804 MW with 45% beam-to microwave power conversion.

The mode convertor design of fundamental coaxial TEM to the lowest asymmetric TE11-mode of a circular waveguide was proposed and optimized with ANSYS HFSS software. It includes axially aligned parts: the input coaxial line with the high voltage insulator, conical coaxial matching line, wave-coax transition section and output circular waveguide. The most losses in this type of convertor caused by the wave of coaxial TE11-mode running back to the microwave source. To minimize these losses, there is the matching conical coaxial line with the cut-off insertion for coaxial TE11-mode. Characteristics of the convertor are as follows: the maximum input peak power – 3GW, the input impedance – 28Ohm, the central operating frequency – 1.14GHz. The power conversion efficiency to the output mode is from 90% upto 100% in the frequency band of 20%.

On of the possible methods of obtaining monochrome X-ray radiation short “flashes” is parametric X-ray radiation (PXR) generated by the nanosecond duration electron beam. For this purpose the powerful electron beam effect on the tungsten crystalline target has been investigated experimentally. The accelerator of the direct effect “Sinus-7” has been used as an electron source, where the electron beam is formed in the flat vacuum diode in the magnetic field. The accelerating pulse duration is 50 ns, the electron energy is 1.1 MeV, the current density on the target surface is ~ 250 A/cm

In recent years, oil and gas exploration are increasingly turning to direct methods to identify accumulations of hydrocarbons (magnetometry, radiometry, geochemical methods, etc.). Similar works are tested high in the Tomsk region, near the Ob basin. In this paper we present some results of testing of geological and genetic models and radiogeochemical occurrence of hydrocarbons in relation to various oil and gas complexes, with the development of neural network methods of analysis and forecasting, formulated proposals for their integrated use.

The paper deals with the application features of capacitive probes for subnanosecond voltage pulse measurements. The relation for the amplitude of distortions determined by the finite electrical length of a capacitive divider was obtained. This relation could serve for quantitative estimation of capacitive divider suitability. Probes of various designs were used for recording the high voltage pulses with subnanosecond voltage changes. The pulse shapes with voltage change durations of 0.2 - 20 ns from different voltage probes were compared. It was shown that the use of capacitive divider with high- and low-voltage arms filled with the same material is more appropriate. This divider provides the same voltage ratio for voltage changes of durations from tens to fractions of nanoseconds.