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Russia and Belarus have a unity of historical and cultural development, long-term organizational and legislative developments, resources for supporting and intensifying integration processes within the Union state. A special place in interstate integration is occupied by the formation of a single economic space that ensures the alignment of common priorities, mechanisms and tools for the economic development of the participating countries. One of the priorities for the development of economically developed countries is the introduction of information and communication technologies in various economic areas, formation of the necessary digital infrastructure and qualified personnel training. In the conditions of transition of the national economies of Russia and Belarus to a digital model of development, the system of institutions that determine the activity of integration processes within the Union state. These factors allow us to conclude that the common economic space of the Union state will develop in new conditions associated with profound changes in political, social, economic and organizational institutions, which actualizes the relevant interdisciplinary research. The authors aim to identify the main challenges and opportunities associated with the institutional development of the common economic space of the Union state in the context of digitalization.

The formation of the microchannel structure of a spark discharge in the gap spike (cathode)-plane of 1.5 mm length in the air of atmospheric pressure was studied by the method of shadow photography. The images with the concurrent descent of microchannel diameter sand the number of microchannel increase in the cathode region on the time interval of 5 ns were recorded. The obtained data are explained in the frames of the microstructure formation mechanism at the expense of the front instability of the ionization wave. The parameters characterizing the process of the microstructure formation are estimated, and they agree with the experimental data. Keywords: spark discharge, ionization wave, ionization instability, microstructure, method of shadow photography.

HgBa 2 Ca 3 Cu 4 O 10+ δ and HgBa 2 Ca 4 Cu 5 O 12+ δ were prepared by high pressure/high temperature technique. The phase composition in the Hg–Ba–Ca–Cu–O system was shown to be very sensitive to synthesis conditions. A variation of the oxygen content in the starting oxide mixture by changing the BaO/BaO 2 ratio allowed the acquisition of Hg-1234 and Hg-1245 in the overdoped state. The heat treatments (nitrogen and oxygen flows, oxygen pressure 100 bar and 2000 bar) resulted in a change of T c s from initial overdoped (116 and 100 K for Hg-1234 and Hg-1245, respectively) to underdoped (95 and 85 K) and, finally, to optimally-doped states (125 and 111 K). The dependencies of T c vs. a -parameter (and, consequently, oxygen content) for these phases exhibit a cupola-shaped behavior, as it was previously found for the lower ( n ≤3) members of the HgBa 2 Ca n −1 Cu n O 2 n +2+ δ series.

Powerful pulse installations are usually used to produce large yields of X-ray radiation. With an increase of the stored energy up to 100 MJ, the costof a single experiment on these installations becomes comparable to the cost of a shot with explosive magnetic generators (EMG), according to expert estimates. The physical scheme of a device with a changeable mass liner forlarge soft X-ray (in the range of 0.3 to 0.5 keV) yields eneration is investigated. The scheme investigated is substantially free from difficulties connected with high precision liners and fast switches for current pulse sharpening.

Efficiency and time jitter measurement results are presented for proportional and drift chambers with 2 mm half gap and CF4:iC4H10 (80:20) gas mixture in the presence of magnetic field. Data were taken on the M15 beam line at TRIUMF for positrons with momentum 35 MeV/c. It is demonstrated that two layers of PCs when combined have better than 99.995% efficiency of positron detection in magnetic fields up to 6 T. The time jitter (RMS) of the sum signal from three layers of PCs does not exceed 2.3, 2.9, and 3.9 ns at B = 0, 3, 6 T, respectively. The time shift of this signal does not exceed 2.0, 2.25, and 4.4 ns at B = 0, 3, 6 T respectively for the positron incident angles (with respect to PC plane normal) ranging from 0 to 60°. Such PCs will serve as zero time trigger for PDC chambers with DME gas in TRIUMF experiment 614 [TRIUMF E614 Proposal (1990), Vancouver, B.C., Canada].

We consider an ALT-1,2-like [1,2] system to deliver up to 60-70 MA currents in the liner load and accelerate ∼20 g/cm cylindrical liners to ∼20 km/s (ALT-1,2: ∼31 MA, ∼13 g/cm, ∼12 km/s). The system is intended for the ALT-3 experiment to test the efficiency of magnetic implosion of impacting liners and to verify the possibility of shock-wave measurements at up to 1 TPa pressures.

A hodoscopic PMT (HPMT) is proposed for the design of a positron emission tomograph (PET). The spatial resolution of a HPMT-based PET element is measured. It amounts to 3.6 and 1.75 mm for the BGO and GSO, respectively. HPMT-based single- and multilayer PET ring designs are suggested.

Summary form only given. Powerful stationary facilities able to generate the current of tens of mega-amperes to the load at a microsecond level are widely applied in many world laboratories to solve a whole series of scientific and applied problems. The paper considers an alternative source of pulsed power on the basis of a small-size (250 mm) disk explosive magnetic generator with flat disk elements and with triangular section inserts in the compression cavities. The design of the generator of this type is described. The results of the experiments conducted with five-element and ten-element generators are presented. The obtained data are analyzed and the conclusions on a possibility of future application of these devices are drawn.

In the three joint VNIIEF/LANL experiments RHSR-0,1,2 with a disk EMG and a three-layer liner system (Al-dielectric-Cu) a method of radial radiography was used to study growth of perturbations amplitude at the boundary between copper layer and polyethylene (in experiments RHSR-0,1) and water (in experiment RHSR-2); the growth occurs during the evolution of the Raleigh-Taylor instability of this boundary.

Good longitudinal symmetry of magnetically driven metal cylindrical liners may be observed at a relatively short time of current rise, for example, in experiments at PEGASUS-2 facility. Because of interaction of the liner with current-conducting edge walls the symmetry of compression may be much worse in experiments with a longer rise time of current delivered by explosive magnetic generators (EMG). The present paper describes the results of study of near-wall effects negative influence on longitudinal symmetry of compression of liners, close in design to experiments at PEGASUS-2 facility, but at an order higher duration of current supplied by helical EMG. The work was conducted within the frames of liner technology program (LT-1 experiments).

In the experiments, the MAGO chamber was used, for the present, only as a device intended for plasma preliminary heating. The explosive magnetic generators with a stored energy of 1-10 MJ are used in the experiments as the sources of electromagnetic energy. The explosive magnetic generators (EMG) are the superpower sources of electric energy. The use of the explosive energy allows one to realize the parameters typical of the large expensive stationary capacitor facilities in the energy-production facilities having a relatively small size.

Describes the MAGO-MTF (magnetised target fusion) approach to fusion energy using a MHD-nozzle device as the thermonuclear target. In MAGO-MTF, thermonuclear reaction ignition has two stages: 1) heated magnetized plasma formation; and 2) adiabatic compression of the obtained plasma and the achievement of thermonuclear reaction burning conditions. The formation of plasma with definite temperature and lifetime is carried out by means of plasma acceleration up to ultrahigh velocities in the MHD Laval nozzle under the influence of quick-increasing magnetic field pressure and by means of the further plasma thermalisation. Some results of the MHD-nozzle device calculations are presented, in which one can see the character of plasma motion and the dynamics of its heating.

Works on the investigation of a magnetized plasma commenced and developed in the framework of MAGO (magnetic compressuring) programme, that got its official status at VNIIEF in 1979. It was directed to the attainment of a thermonuclear ignition in dense targets (without the use of fissionable materials) by means of their compression by liners accelerated to high velocities by a magnetic field. The investigations of the magnetized plasma were focused on the production of a hot ionized low-density plasma pre-heated up to 0.2-1.5 kV and suitable for the subsequent adiabatic pressing by the liner up to thermonuclear temperatures. The development of a new type of plasma chamber has formed the basis for a new area of the works, the calculated and theoretical justification of which has been performed by the theoretical department; the experiments have been arranged and conducted at VNIIEF Electrophysical Department. This chamber has the title 'gaseous ponderomotive unit' (GPU) or gaseous PU, and the system designed for the study of dense targets has come to be known as a liner ponderomotive unit (LPU).

Experiments were conducted on the "CASCADE" electrophysical facility which was used as a source of impulse power for laboratory model of deuterium plasma chamber with a circular MHD nozzle (MAGO chamber). The modes of device's operations were investigated at various values of deuterium pressure in the chamber both with preliminary introduction of magnetic field in the plasma and without it. Depending on conditions of experiment the neutron radiation was generated at the front of increasing current, at its maximum or on a falling down branch of current. Though the experiments were conducted at low energies of plasma chamber powering (100-500 kJ), the stable generation of neutrons was observed. The length of neutron impulse achieved the value comparable to length of neutron radiation being obtained in experiments, in which explosive magnetic generators of multimegajoule energy scale are used (/spl sim/1 /spl mu/sec and more). It was defined the optimal deuterium pressure in the plasma chamber for the used operation modes of the device.

Magnetic compression/magnetized target fusion (MAGO/MTF) is an area of fusion research that is intermediate between magnetic fusion energy (MFE) and inertial confinement fusion (ICF) in time and density scales. In this paper, the authors report the results of experiments exploring a scheme for forming a hot, magnetized plasma possibly suited for subsequent implosion in a MAGO/MTF context. The experiment described here used a copper plasma formation chamber. The outer radius of the plasma volume was 10 cm. The chamber was initially filled with 10 Torr of 50% deuterium, 50% tritium gas seeded with 0.01% neon for diagnostic purposes. The chamber behavior was computationally modeled using two-dimensional magnetohydrodynamic techniques.

Summary form only given. MAGO/MTF concept suggests a two-stage achievement of a thermonuclear reaction ignition:- generation of hot magnetized plasma; compression of the generated plasma and achievement of a thermonuclear reaction. The calculations show that it is possible to separate the processes of formation and compression of hot plasma in MAGO chamber not only in time but also in space by means of plasma transportation to a special compression section.

Summary form only given, as given. Considers the scheme to supply the MAGO chamber with the help of an inductive shunt. In this scheme the time of flow of the preliminary supply current is reduced as compared with the scheme using the explosive closing switch. When supplying the plasma chamber by the helical EMG, the current of preliminary supply is commutated by the closing switch. In the circuit with the closing switch the current flows in the chamber without changing the amplitude till the end of helical generator operation, thus producing a destroying effect on the chamber elements.

Helical explosive magnetic generators (HEMG) represent the inductive generators of electromagnetic energy. Operation of HEMG is based on compression of magnetic field, preliminary delivered to the helical coil, by the metal armature, placed coaxially in the coil center and expanding during an explosion. Circuit compression results in a decrease of its inductance, while the magnetic energy and the current increase. Current in HEMG reaches a magnitude of several dozen million amperes. When using HEMG, the designers, as a rule, try to get the maximum energy the generator is designed for. It means that usually explosive magnetic generators operate under limiting conditions. The objective of this work is to reduce the risk during explosive experiments by obtaining the possibility to develop new, and to use the available, HEMGs with guaranteed margins for the critical parameters.

Experimental observations of plasma behavior in a novel plasma formation chamber are reported. Experimental results are in reasonable agreement with two-dimensional magnetohydrodynamic computations suggesting that the plasma could subsequently be adiabatically compressed by a magnetically driven pusher to yield 1 GJ of fusion energy. An explosively driven helical flux compression generator mated with a unique closing switch/opening switch combination delivered a 2.7 MA, 347 $\ensuremath{\mu}\mathrm{s}$ magnetization current and an additional 5 MA, 2.5 $\ensuremath{\mu}\mathrm{s}$ electrical pulse to the chamber. A hot plasma was produced and 1${0}^{13}$ D-T fusion reactions were observed.