[en] Short communication

[en] An analysis of the turbulent noise spectrum of the current-carrying plasma in the stellarator confirmed the previously published assumption on the decay in the non-isothermal plasma of shortwave suprathermal ion-noise oscillation. From the wide oscillation spectra observed in the ''Uragan'' stellarator of low-frequency plasma oscillations with a characteristic frequency of 1 kHz there is probably a direct relationship to the mechanism for the electron acceleration in the period of current flow

[en] A method and equipment for the fluctuation spectral analysis of microwave radiation are described which has been applied to the study of the probability characteristic of thermal and epithermal radiation of a plasma in the ''Uragan'' stellarator. Quantitative data about statistical properties of the microwave radiation were o btained by means of comparing microwave noises radiated by the plasma with a standard source of the microwave radiation. The results of an analysis of the microwave noise radiation accompanying current and ion-cyclotron heatings of the plasma in the stellarator are presented. The nature of a high-frequency plasma turbulence is discussed

No abstract available

[en] Timely and accurate diagnosis of dissecting aneurysm of the aorta requires combined application of the current methods of examination among which are the obligatory routine X-ray examination, echocardiography and retrograde aortography. Indications to the use of roentgenokymography, tomography and computerized tomography are limited. Magnetic esonance tomography is a promosing method for the diagnosis of dissectinganeurysm but is still not widely used. Use of intravenous digital subtraction angiography is justified in cases when retrograde aortography cannot be performed

[en] The ultra-high frequency (UHF) spectra of a He [7440-59-7] plasma in the stellarator Uragan were measured. The intensity of the radiation was highly irregular in the wavelength region studied and the spectral shape was dependent on the magnetic field used. UHF radiation of short wavelength possesses a noise component, whereas that of long wavelength (lambda approximately 3.1-2.1 cm) has a sporadic non-steady-state character. When the low frequency noise level in the stellarator is small, the observed oscillogram indicates hard x-ray and radio noise of the plasma. The intensity of hard x-rays decreased with the strength of the electric field and with an increase in the initial pressure of the working gas or the magnetic field. The radio noise spectra of current-carrying plasma were determined with the help of external magnetic antenna, and the observed spectra were analyzed

No abstract available

[en] Experimental results on investigation of local energy release in plasma resulting in instability break-down in ''Uragan-2'' stellarator are generalized in the case of plasma heating by a powerful current pulse. Correlation between variation of poloidal magnetic flux in plasma filament, abnormal heating of electrons and ions and breaks-down in stellarators is established. Zones of abnormal energy produiction in plasma are identified. Spatial localization of electron acceleration and heating on resonance magnetic surfaces is discovered. Principle feasibility of break-down suppress both with an increase of magnetic field strength and transition of a heavy-current discharge into a regime of abnormal energy release all over the filament volume is discovered. The regime of abnormal energy release is typical for magnetic force lines overconnection in turbulent plasma and is called ''stress-heating'' of a plasma. Pulsed plasma heating is conducted under above conditions, where value of mean ''beta'' of plasma attains 0.5%

No abstract available

[en] With the help of the frame-type antenna integrated into the helical winding of the U-3M torsatron, studies of the RF power coupling efficiency and of plasma production in the ICRF (ω < ω_ci) have been performed. Dense hydrogen plasma (n-bar_e > 10¹³ cm^-3) has been produced in the broad range of torsatron magnetic field changes B₀ = 0.35 - 0.8 T when RF power of ∼ 100 kW level was radiated from the new antenna at the fixed frequency f₀ = 5.6 MHz. The antenna coupling to a produced plasma increased on growing the plasma density (R_ptmax = 0.5 Ohm at n-bar_e 1.4 x 10¹³ cm^-3). TiN coating of the antenna current-carrying surfaces lowered the impurity influx into the discharge and enhanced the temperature of the plasma produced. (author). 9 refs, 4 figs