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The high-power hot plasma stream of E-beam heated plasma in the GOL-3 facility is used for exploratory plasma stream-target interaction experiments under conditions rather typical for the thermal quench phase of ITER tokamak plasma disruptions. The recent experimental results are presented.

New results are presented on studying the beam-plasma interaction and plasma heating dynamics at the INAR device. The specific features of the generation of 'hot' (E>approximately 1keV) plasma electrons containing the main part of the plasma energy are studied. In the case of a beam with a small initial angular spread, the 'hot' electrons are mainly generated near the point where the beam is injected into the plasma. Also reported are the results of the experiments in which the magnetic field in the beam-plasma interaction region was increased up to 70 kOe. In this case, at the plasma length of 75 cm, the total beam energy losses exceed 40%. The growth of the plasma energy content at higher magnetic field is observed. The first stage of the GOL-3 experiment is described which is aimed at the study of the plasma heating of a solenoid by a 100 kJ microsecond electron beam. This experimental device is ready for operation.

After acute hypoxia (3 hrs, P-200 mm Hg) content of total phospholipids and of their fractions was not altered in rat lung parenchyma, but the phospholipid composition, changed due to preadministration of hydrocortisone or insulin, was normalized. After the hypoxia concentration of phospholipids in surfactant was decreased mainly due to a loss of phosphatidyl choline; the phenomenon was noted and after preadministration of the hormones.

Pretreatment of rats with hydrocortisone or protamin-Zn-insulin within 4 days altered in subsequent acute hypoxia (3 hrs, "height" 10 000 m) the isoenzyme spectrum of LDH in lungs, liver tissue and kidney cortex. The differences in alterations in the activity and content of LDH isoenzymes were observed in tissues with various types of metabolism.

The activities of gluconeogenic enzymes of the rat kidney cortex was studied after exposure to lowered atmospheric pressure (200 mm Hg) for 3 hours. The hypoxic stress was found to cause an increase in the activities of phosphoenolpyruvate carboxykinase and alanine aminotransferase, but failed to affect significantly the activities of fructose-1,6-diphosphatase, glucose-6-phosphatase, and aspartate aminotranspherase. The ratio of glucose-6-phosphatase/hexokinase activities was increased under these conditions.

A single total body cooling was found to cause a more distinct alteration in carbohydrate metabolism in lung tissue of male rats as compared with female rats. These metabolic alterations were less distinct in castrated males. Preadministration of one of the sex hormones (testosterone, estradiol or progesterone) into the castrated males led to normalisation of carbohydrate metabolism in cooling; among the sex steroids estrogen was the most effective.

A method for determining the spatial structure of a high-power relativistic electron beam is described. Using an absolutely calibrated CCD collector, the thermal-radiation brightness distribution of the beam-collector surface is registered in the visible and near-IR spectral regions and then converted into a spatial distribution of the beam energy deposition in a target. This method is applied at a high specific beam-energy flux (∼1 kJ/cm2), one which causes noticeable erosion of the beam collector.

The GOL-3-II facility was used for the investigation of the interaction of a high-power plasma stream with solids. The experiments allowed the study of the properties of the dense plasma formed in front of materials under action of the fast electrons flowing out the open trap. Target plasma from entrance foil with density 10 16 cm -3 has the expansion velocity 2-4 10 6 cm/c. Explosive-like erosion of the exit graphite receiver was been observed. Formation of a dust cloud is a feature of this phenomenon. Properties of the dusty particles are discussed.

A set of diagnostics for plasma spectroscopy was developed for multimiror trap GOL-3. It includes survey spectrometer with spatial resolution and the high spectral resolution complex for line shape analysis. The systems allow recording waveforms of plasma radiation with spectral resolution of 0.01 nm and measure spatial distribution of line radiation intensity (simultaneously in π and a components). Analysis of radiation spectra was used for investigation of impurities structure and dynamics. Precise measurements of spectral line shape were used for finding the electron density and ion temperature from a line broadening. Description of the equipment and experimental technique as well the recent results are presented in the paper.

Phenomenon of fast heating of plasma ions in the multimirror trap GOL-3 is discovered and explained. An essence of effect is that ion component of the plasma is heated during electron beam injection much faster (at 100 - 1000 times) than due to binary electron-ion collisions. An analysis of experimental results is presented and discussed. A model of fast non-Coulomb ion heating is suggested.

Review of the experimental results for the last two years on study of dense plasma heating and confinement in a long multimirror trap GOL-3 is presented. This facility is an open trap for confineme...

Overview of the activity on the development of the new multiple-mirror trap GOL-NB to be built in Budker Institute will be presented. This device to be build in BINP in several years as a deep conversion of the existing GOL-3 facility. The device will consist of a central trap with two 0.75 MW neutral beams, two multiple-mirror solenoids, two expander tanks and a plasma gun that creates start plasma. Plasma will be NBI-heated and confined in the central trap that is essentially a compact version of the GDT device with the well-known physics. The multiple-mirror sections should decrease the power and particle losses along the magnetic field. The main physical task of GOL-NB is the direct performance demonstration of the multiple-mirror sections that will change the escaping plasma flow and equilibrium plasma parameters in the central trap depending on the magnetic configuration chosen. In this paper, we will discuss new results in scenario modeling and progress in the hardware, including neutral beam injec...

Dynamics of light impurities at multimirror trap GOL-3 was studied using imaging spectroscopy diagnostics in VUV and visible spectral range. The results of impurity balance and transport simulation as well as comparison with measurements are presented in this paper. Concentration of impurities in plasma and diffusion coefficient are found out from the measurements. Suitability using VUV and XUV spectroscopy for measuring main plasma parameters is considered.

A description of the GOL-3-II facility and the first experimental results obtained on this new device are presented. This facility was constructed as part of the second stage of the GOL-3 programme for studying the interaction of microsecond electron beams with a plasma and its fast heating. The plasma column of the GOL-3-II facility is 12 m in length instead of 7 m for the first stage of GOL-3. The energy content of the capacitive storage for magnetic field supply has been increased from 10 MJ to 15 MJ. This allows us to have a magnetic field of up to 5 T in the homogeneous part of the solenoid and up to 10 T in its end mirrors. The expected key feature of the upgrading is an essential increase in the energy content of the electron beam injected into the plasma. The high-power electron beam generator U-2 is now used for the new beam - plasma interaction experiments with possible beam energy content of up to 0.3 MJ. It is shown experimentally that transportation of a 0.2 MJ electron beam through the 12 m plasma column is possible under conditions of almost full current neutralization. The collective beam - plasma interaction results in a plasma heating of up to 1 - 2 keV electron temperature at density.

Two separate topics on a pellet injection activity at the multimirror trap GOL-3 are presented. The first topic is connected with studies of influence of a high-energy-density plasma on solids. A carbon pellet of 2-mm diameter was injected into the plasma for this purpose. The second discussed topic is a status of works on a cryogenic pellet injector for plasma fueling at GOL-3.

Recent results of the experiments at GOL-3 facility are presented. In present configuration of the device, plasma with a density of 10 14 ÷10 16 cm -3 is confined in a 12-meter-long solenoid, which comprises 55 corrugation cells with mirror ratio B max /B min =4.8/3.2 T. The plasma in the solenoid is heated up to 2-4 keV temperature by a high power relativistic electron beam (∼1 MeV, ∼30 kA, ∼8 μs, ∼120 kJ) injected through one of the ends. Mechanism of experimentally observed fast ion heating, issues of plasma stability and confinement are discussed.

A short review of recent results obtained at the GOL-3-II facility is presented. This facility is an open trap with 12 m long plasma column with a longitudinal magnetic field of 4.5 T in the unifor...

Recent results of experiments on high-energy content E-beam application for plasma heating in a multimirror trap GOL-3 are presented. Conditions for optimal neutralization of injected beam and its stable transport through long plasma column are defined. Effective electron and ion heating of plasma is observed.

A complex of visible-region spectral diagnostics for studying high-temperature plasma at the GOL-3 facility is described. The complex includes three spectral instruments with different spectral resolutions, apertures of optics, and spatial resolutions. These instruments are equipped with digital recording units that make it possible, depending on the task being performed, to obtain highly resolved plasma-radiation spectra with either temporal or spatial resolution. The technique for measuring the electron density, ion temperature, and magnetic field are presented, along with the corresponding results.

Activity of enzymes of gluconeogenesis in the renal cortex was studied in rats after exposure to a reduced atmospheric pressure (200 mm Hg) for 3 h. Hypoxic stress was shown to lead to an increase in the activity of phosphoenolpyruvate carboxykinase and alanine aminotransferase but to have no significant effect on activity of fructose-1,6-diphosphatase, glucose-6-phosphatase, and aspartate-aminotransferase. The ratio between glucose-6-phosphate activity and hexokinase activity was increased under these conditions.

Acute hypoxic hypoxia leads to increased glucose formation by rat liver slices from pyruvate,α-glycerophosphate,α-ketoglutarate, and fructose. During exposure to hypoxia after prolonged administration of hydrocortisone acetate, increasing gluconeogenesis from the above-mentioned substances and also from alanine, lactate, and glycerol, the rate of glucose synthesis in liver slices was higher than in the control but lower than after the action of hydrocortisone alone.