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Electrically charged (up to 107e) macroscopic superconducting particles with sizes in the micrometer range confined in a static magnetic trap in liquid nitrogen and in nitrogen vapor at temperatures of 77–91 K are observed experimentally. The macroparticles with sizes up to 60 μm levitate in a nonuniform static magnetic field B ~ 2500 G. The formation of strongly correlated structures comprising as many as ~103 particles is reported. The average particle distance in these structures amounts to 475 μm. The coupling parameter and the Lindemann parameter of these structures are estimated to be ~107 and ~0.03, respectively, which is characteristic of strongly correlated crystalline or glasslike structures.

The dynamics of two-dimensional clusters consisting of 7 and 18 particles whose interaction is described by a screened Coulomb potential has been numerically simulated by the Langevin molecular dynamics method. With the use of the data obtained for the displacements and velocities of particles, the functions of the “mean first-passage time” dynamic entropy have been obtained for clusters having different kinetic temperatures close to the conditions of laboratory experiments with macroparticles in a gas-discharge plasma. Three phase states of the small systems under consideration—crystal, liquid, and transient—have been observed. A mechanism of phase transitions under consideration has been described. The method proposed to analyze the dynamics of systems can be used for extremely small structures.

The existing view of the photoemission properties of lunar regolith does not provide the unambiguous treatment of the parameters and distributions of photoelectrons over the illuminated part of the Moon. This is indicated by the present calculations of the density, temperature, and distribution function of photoelectrons. It has been demonstrated that the quantum yield of lunar regolith is the main parameter determining the generation of photoelectrons near the surface of the Moon. At present, this parameter is determined with significant uncertainty. The measurement of the quantum yield of regolith directly on the surface of the Moon has been proposed as a variant of the solution of the indicated problem. Such measurements can be performed in the framework of future lunar missions.

A dusty plasma layer formed near the illuminated part of the surface of the Moon under the action of ultraviolet radiation, as well as fast and slow solar wind, has been numerically simulated. The numerical calculations including the photoemission properties of lunar regolith samples delivered to the Earth have been compared to estimates within known theoretical models. It has been shown that the flux of solar wind particles plays an important role in the formation of the surface photoelectron layer. The conditions of the charging and stable levitation of dust particles in the surface plasma layer of the Moon have been analyzed.

Various regimes of Brownian motion of interacting (charged) dust particles in a plasma have been experimentally studied. A new analytical model for the correct description of the mass transfer dynamics of such particles, including the transition between the ballistic and diffusion regimes of their motion, has been proposed and experimentally tested.

The formation of strongly nonideal Coulomb systems of a large number (∼104) of charged diamagnetic macroparticles in a cusp magnetic trap under microgravity conditions has been experimentally studied. The experiments have performed in the Russian segment of the International Space Station in the framework of the Coulomb Crystal experiment. Using the data of the videorecording of the positions of the particles in the magnetic trap, the magnetic susceptibility and charge of the particles have been estimated and the period of the oscillations of the cloud of the particles, as well as the damping rate of oscillations, has been determined.

The formation of dusty plasma structures has been experimentally investigated in a cylindrical dc discharge in axial magnetic fields up to 2500 G. The rotation of the dusty plasma structures about the discharge symmetry axis with a frequency depending on the magnetic field has been observed. When the field increases to 700 G, the displacement of dust particles from the axial region of the discharge to the periphery, along with the continuation of the rotation, has been observed. The kinetic temperatures of the dust particles, the diffusion coefficients, and the effective nonideality parameter have been determined for various magnetic fields. The explanation of the features in the behavior of the dust particles in the discharge in the magnetic field has been proposed on the basis of the analysis of ambipolar diffusion in the magnetized plasma. The maximum magnetic field at which the levitation of the dust particles in the discharge is possible has been estimated.

Charging of dust particles in a plasma with the two-temperature energy distribution of electrons has been studied. It has been shown that the dust-particle potential divided by the electron temperature decreases with increasing electron temperature in the plasma with cold ions. Owing to this behavior, the potential of the dustparticle surface increases with the electron temperature more slowly than the linear function and is lower than the electron temperature (divided by the elementary charge) for T e > 5.5 eV in hydrogen and for T e > 240 eV in argon. The fraction of fast electrons at which these electrons begin to contribute to the charge of dust particles has been determined. It has been shown that the charge of micron particles can reach 106 elementary charges. The effect of the cold and thermal field emission on the charge of dust particles has been analyzed. The possibility of obtaining ultrahigh charges (to 107 elementary charges on dust particles with a radius of 50–100 μm irradiated by a 25-keV 1-mA electron beam has been demonstrated.

The results of the experimental study of heat transfer processes in liquid dusty structures are reported. The experiments have been carried out for aluminum oxide particles in an rf discharge plasma. The thermal conductivity and thermal diffusivity of the dusty plasma component have been determined by analyzing the steady and unsteady heat transfer processes. The temperature dependence has been obtained for these quantities, which is in qualitative agreement with numerical simulation results for a simple one-atomic fluid.