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This paper presents a short review of plasma-optical mass-separation and defines the fields for its possible application. During theoretical studies, numerical simulations, and experiments, the effect of the azimuthator finite size and of the vacuum conditions on the mass separator characteristics was revealed, as well as the quality of different-mass ion separation. The problems, solving which may lead to a successful end of the mass-separation plasma-optical technique implementation, were specified. V C 2014 AIP Publishing LLC. [http://dx.

Results of designing the hardware-software complex ensuring automatic recording, cleaning, and approximation of signals of the energy analyzer with a retarding potential protecting from breakdowns (electron current) and voltage spikes that cannot be attributed to the studied physical process, are presented. The complex is successfully applied for corpuscular diagnostics in experiments on plasma-optical mass separation. INTRODUCTIONThe primary characteristic of particles in plasma is the ion (electron) energy distribution function, which is measured using energy analyzers of charged particles. Among them multigrid energy analyzers with the retarding potential (RFA) stand out as universal wideaperture devices with a high light-gathering power and small sizes, which are placed directly in plasma at a point where its parameters are measured.The signal from the RFA collector-retarding curve I i = φ(E i )-is differentiated for obtaining energy ion spectra: f(E) = -dI i /dU, where I i is the ion current to the collector of the RFA; E i is the ion energy; and U is the potential of the retarding grid of the RFA, which varies from the maximal value being equivalent to the maximum ion energy, to zero. The noise ("noise" of plasma, local breakdowns, and magnetic pickups) are imposed on the delay curve when operating with plasmas and plasma accelerators.Development of a universal plasma-optical mass separator [1, 2], which can be used, e.g., for dividing spent nuclear fuel into three fractions, requires that many preliminary experiments on determination of paths of separated ions should be performed. In this case, the ions have a wide energy spectrum and large angular spread, requiring applications of energy analyzers movable in the ion flux propagation space, which, in addition, should have an automatic signal recording and preprocessing system. For our purposes, the most acceptable are RFAs, for which, however, the data handling process is the most labor-consuming as compared to analyzers of

In the magnetic barrier of the azimuthator of the POMS-E-3 plasma optical mass separator, a 20–40 times decrease in the ion flux has been observed. Such a phenomenon deems the process of separation of a multi-component ion beam into elements inefficient. Upon conducting an in-depth theoretical analysis of the problem regarding the passage of the ion stream across the magnetic barrier while considering the walls and in the absence of those, it has been concluded that the problem has a unique steady-state solution allowing for the ions to pass at any values of magnetic field induction, regardless of the density and thermal dispersion in the incoming ion beam. The maximum value of the ion density at the output of the magnetic barrier is estimated as n∞∼β1πW0e2Δ2, where W0 stands for the ion energy at the input of the magnetic barrier and Δ equals the length of the magnetic barrier, while e signifies the electron charge and β varies from 1/9 to 1.

Presented are the results from tailoring the retarding field energy analyzer to measure the degree of charge compensation and regular patterns in the separations of ions of different mass, with the multicomponent ion flow spreading out in the plasma-optical mass separator model.

This paper presents separation results of a mixture of nitrogen, argon and krypton ions in the process of plasma-optical mass separation on the POMS-E-3 separator model. We determined the behavior of the separation with a change in the value of magnetic field induction in the azimuthator and in the degree of compensation of the spatial charge in ion flows. An analysis is performed for experimental data by correlation with the results of a theoretical study and numerical experiments. The objectives of future experiments are outlined.

In a plasma accelerator with an anodic layer (PAAL), we discovered experimentally the effect of 'super-acceleration' of the bulk of the ions to energies W exceeding the energy equivalent to the discharge voltage V d. The E×B discharge was ignited in an environment of atomic argon and helium and molecular nitrogen. Singly charged argon ions were accelerated most effectively in the case of the largest discharge currents and pressure P of the working gas. Helium ions with W>eV d (e being the electron charge) were only recorded at maximum pressures. Molecular nitrogen was not accelerated to energies W>eV d. Anomalous acceleration is realized in the range of radial magnetic fields on the anode 2.8×10-2 B rA 4×10-2 T. It was also found analytically that the cathode of the accelerator can receive anomalously accelerated ions. In this case, the value of the potential in the anodic layer becomes higher than the anode potential, and the anode current exceeds some critical value. Numerical modeling in terms of the developed theory showed qualitative agreement between modeling data and measurements.

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