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The explosion of a tungsten wire in a weak longitudinal magnetic field is studied. The longitudinal magnetic field is shown to decrease the rate of rise of initial perturbations and to stabilize the process. This makes it possible to calibrate analytical models of conduction, equations of state, and radiation paths. Good agreement between observed and analytical electrical and optical patterns of the wire explosion and expansion is obtained.

Approximate 1.5-dimensional MHD equations are derived that describe the quasi-adiabatic compression of a thin plasma column by a longitudinal magnetic field. The parameters of the compressed plasma are obtained analytically as functions of the initial conditions and longitudinal field. The stability of plasma compression against the Rayleigh-Taylor instability is investigated. It is shown that, in the Z-Θ-pinch geometry, increasing the longitudinal magnetic field makes it possible to achieve radial compression ratios of 20–30 without violating the cylindrical symmetry of the column. The possibility of thermonuclear ignition in a thin plasma column in a Z-Θ-pinch configuration is studied. The ranges of the initial plasma densities and temperatures and the initial lengths of the plasma column that are needed to achieve ignition in a plasma compressed by a factor of 20–30 are determined. The parameters of the electromagnetic energy source required to achieve such a high plasma compression are estimated.

Summary form only given. The paper presents investigation results on development of soft X-ray radiation sources based on imploding multi-wire Z-pinches, powered from magneto-cumulative generators. Parameters of the source, realized with fast helical magneto-cumulative generator MCG-200, are close to calculation results: an energy of the X-ray radiation is 180 kJ in a pulse with the width at half height of ~20 ns, the pinch plasma temperature is 65 eV, a current amplitude in the liner load is 5.3 MA at a rise time of 400 ns. The research on optimization of the X-ray radiation source parameters with the power source based on the magneto-cumulative generator of 240 mm diameter are being continued. Up to now the current of 14 MA amplitude and rise time of 1.3 mus could be supplied into the liner load . A length of the generated pulse of the X-ray radiation is 60 ns at half height, the pinch plasma temperature is ~60 eV.

Summary form only given. EMIR (an abbreviation from Russian: electro-magnetic X-ray radiation source) is a facility that should provide generation of high-power fluxes of soft X-ray radiation with an energy in a pulse of ges10 MJ and a power of ges500 TW. In the paper we present a current state of the research of the EMIR main units: disk magneto-cumulative generators, being the base of current pulses formers of tens megamperes amplitude at a rise time of ~1 mus; plasma current opening switches, providing shortening of the current rise front of the explosive generators up to les100 ns; and devices of the magneto-cumulative generators energy transformation into the soft X-ray radiation. Analysis of results of the experimental works is carried out, and perspective directions of further research are proposed.

In the paper we discuss experiments on wire liner systems powering from helical and disk magneto‐cumulative generators with a current from 2…3 MA up to 20 MA at current rise time from 0.3 μs to 1 μs, respectively. At currents level up to 4 MA maximum yield of soft x‐ray radiation was more than 100 kJ at plasma pinch temperature of 55 eV. At currents up to 20 MA an expected yield of soft x‐ray radiation exceeds 1 MJ.

Developed in RFNC-VNIIEF pulsed energy source, based on ten-elements disk (of 240 mm diameter) magneto-cumulative generator (DMCG-240) with electro- explosive foil current opening switch (EFOS), makes it possible to form a current pulse having an amplitude up to ~20 MA and a rise time of-1-1.5 mus in a liner load. Available experimental data on K-line generation of different chemical elements using gas-puff and multi-wire Z-pinches at long (0.8 mus-1 mus) implosion times show that at these times for reproducibility and enhancement of generating X-ray power the liner system in the form of several nested cascades can be employed successfully. For effective conversion of the stored electromagnetic energy of the source into the kinetic energy of the imploding Z-pinch at sub-nanosecond current rise front the initial radius of the most-external cascade should be large enough (6-10 cm). In this paper we present the result of numerical simulation of the experiment at DMCG-240 with EFOS facility on soft X-ray radiation pulse generation in configuration of nested Z-pinch. The calculations are held on Eulerian difference grid in the frameworks of two- dimensional (in r-z plane) radiation magnetic hydrodynamics (RMHD) taking into account equations of electro-technical circuit.

Presented are the schematic and description of VNIIEF-designed complex with energy sources based on explosive magnetic generators, assigned for acquisition and investigation of dense high-temperature plasma macrovolumes. Activities in this field imply study of several adiabatic compression circuits, each of them featuring pre-ionization and plasma heating by laser radiation. Complex verification results are presented offered by the following setup: creation and heating of deuterium plasma directly inside of MC-1 generator operating cavity with further compression by longitudinal magnetic field.