The details of the charged particle separation by mass in the configuration with axial magnetic and radial electric fields are studied. The radial electric field, oriented to the discharge axis, is induced in a background reflex discharge with a hot cathode (−550 V, 8–14 A). The plasma source is based on a hot cathode arc discharge with independent metal vapor injection (18–21 V, 30 A) was situated at 18 cm from the axis. It was shown that the separated Ag + Pb mixture is transported across the magnetic field under the background discharge electric field. Effective separation is possible in such a system, while the separation coefficient increases from 4.9 to 6.2–8.4 when the mixture injection point is moved away from the background discharge axis from 18 to 23 cm. The effect of mixture injection on the plasma potential distribution is examined. It was shown that the presence of a plasma source of separated substances can cause a local (1–2 cm) distortion of the background plasma potential profile. Such distortion, as well as fluctuations of the background plasma potential, can significantly affect the width of the deposited spots of separated substances.

The possibility of controlling the electrostatic field distribution in plasma has yielded wide prospects for modern technologies. As a magnetic field primarily allows for creating electric fields in plasma, it serves as an additional obstacle for the current flow through a medium. In the present paper, an axially symmetric system is considered in which the magnetic field is directed along the axis and concentric electrodes are located at the ends. The electrodes are negatively biased. A model which solves the problem of the radial distribution of the plasma potential inside the cylindrical plasma column supported by the end electrodes is proposed. The most commonly encountered configurations of the electrical connection for the end electrodes are considered, and the particular solutions to the problem of the radial distribution are presented. The contribution of ions and electrons to the transverse conductivity is evaluated in detail. The influence of a thermionic element on the radial profile of the plasma potential is considered. To verify the proposed model, an experimental study of the reflex discharge is carried out with both cold electrodes and a thermionic element on the axis. A comparison of the computational model results with experimental data is given. The presented model makes it possible to solve the problem concerning the plasma potential distribution in the case of an arbitrary number of end electrodes, and also to take into account the inhomogeneity of the distribution of plasma density, neutral gas pressure and electron temperature along the radius.

The mass separation of chemical element mixtures is a relevant task for numerous applications in the nuclear power industry. One of the promising approaches to solve this problem is plasma mass separation. In a recent study, the efficiency of plasma mass separation in a configuration with a potential well and a homogeneous magnetic field was experimentally demonstrated. This article examines the possibility of increasing the distance between the deposition regions of charged particles with different masses by varying the profile of the electric field potential. Such correlation can be considered as the control in a system of active particles. A cylindrical coordinate system is used. The electric field is axially symmetrical, and the magnetic field is directed along the axis of the symmetry. The corresponding mathematical problem was solved in a general way. The criteria for increasing the distance between the deposition areas of the “light” and “heavy” components of the mixture have been formulated. A high sensitivity of particle trajectories to the electric field potential in the region of the pericentres of the trajectories of charged particles was detected. Recommendations for the practical implementation of the optimal spatial separation of ion fluxes are proposed.

This work is devoted to determining the azimuthal ion rotation velocity in a reflex discharge with a thermionic cathode. For the experimental determination of the ion velocity, a Mach probe with directional particle collection was used. The Mach probe rotation velocity measurements are compared with the drift speed in crossed Ex B fields, where the radial electric field is measured with an emissive probe. The rotation of the plasma was found to be predominantly due to this drift, corrected for centrifugal effects. One of the important results of the work is the determination of the ion temperature. The obtained value T_i=0.12 eV, agrees with the ion temperature estimates in works with similar experimental conditions. A general parameter has been obtained that makes it possible to estimate the necessity to take into account centrifugal effects under given conditions. Keywords: plasma, thermionic cathode, reflex discharge, ion rotation, crossed fields.

This work is devoted to determining the azimuthal ion rotation velo city in a reflex discharge with a thermionic cathode. For the experimental determination of the ion velo city, a Mach probe with directional particle collection was used. The Mach probe rotation velocity measurements are compared with the drift speed in crossed E × B fields, where the radial electric field is measured with an emissive probe. The rotation of the plasma was found to be predominantly due to this drift, corrected for centrifugal effects. One of the important results of the work is the determination of the ion temperature. The obtained value T_i = 0.12 eV, agrees with the ion temperature estimates in works with similar experimental conditions. A general parameter has been obtained that makes it possible to estimate the necessity to take into account centrifugal effects under given conditions.