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1.
Two charged dust particles inside a cloud of charges are considered as Debye atoms forming a Debye molecule. Cassini coordinates
are used for the numerical solution of the Poisson-Boltzmann equation for the charged cloud. The electric force acting on
a dust particle by the other dust particle was determined by integrating the electrostatic pressure on the surface of the
dust particle. It is shown that attractive forces appear when the following two conditions are satisfied. First, the average
distance between dust particles should be approximately equal to two Debye radii. Second, attraction takes place when similar
charges are concentrated predominantly on the dust particles. If the particles carry a small fraction of total charge of the
same polarity, repulsion between the particles takes place at all distances. We apply our results to the experiments with
thermoemission plasma and to the experiments with nuclear-pumped plasma. 相似文献
2.
We have studied the interaction of charged particles with single-walled metallic nanotubes by solving Poisson’s equation with appropriate boundary conditions. Numerical results for the energy dispersion relations as a function of the wave vector are presented when the charged particle is inside or outside the nanotube. 相似文献
3.
Resonant scattering ("scattering through waves") of ions on dust particles in plasmas is considered in the framework of the kinetic theory which consistently takes into account ion-dust collisions and dust charge fluctuations. Resonance with low frequency dusty plasma modes can enhance the ion-dust scattering cross section and the ion drag force on dust particles. 相似文献
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5.
V. N. Tsytovich 《JETP Letters》2003,78(12):763-767
A physical interpretation is proposed for the collective attraction of dust particles, leading to pairing of likely (negatively) charged dust particles, the formation of dust molecules, and the emergence of other complexes containing a large number of dust particles (in the limit, dust plasma crystals). The value of the spacing between particles in such dust structures estimated on the basis of the proposed mechanism of attraction corresponds to the observed interparticle distances in the crystal lattices of recently discovered plasma-dust crystals. The proposed mechanism may form the basis for interpreting various phenomena frequently observed in dusty plasmas. 相似文献
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7.
Propagation of both low and high frequency waves in a plasma consisting of electrons, ions, positrons and charged dust particles
have been theoretically studied. The characteristics of dust acoustic wave propagating through the plasma has been analysed
and the dispersion relation deduced is a generalization of that obtained by previous authors. It is found that nonlinear localization
of high frequency electromagnetic field in such a plasma generates magnetic field. This magnetic field is seen to depend on
the temperatures of electrons and positrons and also on their equilibrium density ratio. It is suggested that the present
model would be applicable to find the magnetic field generation in space plasma. 相似文献
8.
In this Letter the authors have shown that the tunneling of electrons through a potential energy barrier around a negatively charged particle in a dusty plasma must be taken into account in the evaluation of the accretion current. Both the linear and nonlinear screenings have been considered. 相似文献
9.
Zygmunt Dudzicz 《Journal of Electrostatics》2012,70(1):72-76
The hybrid-type electric curtain (HTEC) comprises a planar electric curtain and a perpendicular planar condenser. Serial cylindrical electrodes are supplied with AC voltage, whereas the condenser is fed with DC voltage. HTEC allows for better control of the particle position shift in space. The particle oscillation path within the hybrid curtain has been photographically analysed. The changing particle path was recorded according to a DC changing voltage value and a constant AC voltage value. The aim of the paper is to describe a successful method that enables one to experimentally determine the region where the particle can be stably oscillated. 相似文献
10.
Considering the Boltzmann response of the plasma ions and electrons and inertial dynamics of the charged dust grains, the
possibility of very weak compressive soliton near the continuum limit of the dust population has been inferred. It is concluded
that the behaviour of such coherent structures could be well described by the numerical analysis of the derived nonlinear
classical energy integral equation for bounded solutions. These seem to be higher order dispersive structures within acoustic
limit of the nonlinear turbulence. It is observed that the dust density enhancement beyond the continuum threshold causes
regular increment in width and amplitude of the soliton structures. It is found that the soliton amplitude sensitively depends
on the massive impurity’s population. These coherent structures could be visualized as weakly charged solitary dust clouds
of finite extension (∼ plasma Debye length) within Boltzmann environment of plasma particles in their local surroundings.
The seeding mechanism of such clouds may be attributed to some plasma instabilities driven by either internal or external
free energy sources. Numerical analysis of the problem concludes that the experimental observations of such clouds could be
possible in low density plasma regime. It is deduced that for plasma density ∼ 106 cm-3 at temperatures of a few electron volts and for micron to l0nm sized dust grains, the observation of such structures could
be possible within wide range variability of the dust population density. 相似文献
11.
A. V. Fedoseev G. I. Sukhinin T. S. Ramazanov S. K. Kodanova N. H. Bastykova 《Thermophysics and Aeromechanics》2011,18(4):615-627
The effect of dust particle concentration on gas discharge plasma parameters was studied through development of a self-consistent
kinetic model which is based on solving the Boltzmann equation for the electron distribution function. It was shown that an
increase in the Havnes parameter causes an increase in the average electric field and ion density, as well as a decrease in
the charge of dust particles and electron density in a dust particle cloud. Self-consistent simulations for a wide range of
plasma and dust particle parameters produced several scaling laws: these are laws for dust particle potential and electric
field as a function of dust particle concentration and radius, and the discharge current density. The simulation results demonstrate
that the process of self-consistent accommodation of parameters of dust particles and plasma in condition of particle concentration
growth causes a growth in the number of high-energy electrons in plasma, but not to depletion of electron distribution function. 相似文献
12.
Taking into account the image force on the electron and Debye shielding an expression for the reduction in the work function for a spherical metallic particle in a dusty plasma on account of the negative charge on the surface has been derived. The dependence of the reduction of the work function on the charge on the particle and Debye radius has been tabulated. The effect of this reduction on the thermionic and photoelectric emission and accretion of electrons by the particle has been discussed. As an interesting application of the work, the observed enhancement of the photoelectric emission from individual micron size grains with increasingly negative surface potential has been explained; the grains were selected from samples of dust collected in the Apollo-17 and Luna-24 missions. 相似文献
13.
We present an exact solution of Einstein’s equations representing interpenetrating clouds of rotating dust. The solution is
a member of the van Stockum class; it contains singularities at the centres of the clouds. These are sources of the angular
momentum which is displayed by the metric at infinity. It is not clear whether the rotating dust contributes to the angular
momentum. In the case of two clouds there is a conical singularity between the central ones. For three clouds the conical
singularity may be absent. 相似文献
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15.
A. V. Filippov V. E. Fortov A. F. Pal’ A. N. Starostin 《Journal of Experimental and Theoretical Physics》2003,96(4):684-694
The decay of a dusty plasma in a photoemission cell under microgravity conditions is investigated on the basis of the method of nonlocal moments. It is founds that plasma decay in space experiments occurs in accordance with the mechanism of free electron diffusion followed by dust particle drift. An analytic solution is found for the evolution of radial distributions of the dust particle concentration and the electric field under the experimental conditions. The effect of abnormally high temperatures of dust particles is considered. The effect of axial magnetic fields on the decay of dusty plasma is investigated. It is shown that the plasma decay in a magnetic field is governed by the ambipolar diffusion mechanism, the decay being prolonged up to 103 s in a magnetic field on the order of 103–104 G in strength. 相似文献
16.
In this review we consider the effective interaction force of identically charged nonrelativistic particles (electrons, light and heavy atoms nuclei) in a strong pulsed laser field. It is shown that under certain conditions, the effective interaction force can become a force of attraction. This effect significantly changes the kinematics of the interaction between the particles and can lead to bound states. 相似文献
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18.
Yu. S. Akishev V. B. Karal’nik A. V. Petryakov A. N. Starostin N. I. Trushkin A. V. Filippov 《Journal of Experimental and Theoretical Physics》2017,124(2):231-243
The ultrahigh charging of dust particles in a plasma under exposure to an electron beam with an energy up to 25 keV and the formation of a flux of fast ions coming from the plasma and accelerating in the strong field of negatively charged particles are considered. Particles containing tritium or deuterium atoms are considered as targets. The calculated rates of thermonuclear fusion reactions in strongly charged particles under exposure to accelerated plasma ions are presented. The neutron generation rate in reactions with accelerated deuterium and tritium ions has been calculated for these targets. The neutron yield has been calculated when varying the plasma-forming gas pressure, the plasma density, the target diameter, and the beam electron current density. Deuterium and tritium-containing particles are shown to be the most promising plasmaforming gas–target material pair for the creation of a compact gas-discharge neutron source based on the ultrahigh charging of dust particles by beam electrons with an energy up to 25 keV. 相似文献
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20.
We have investigated analytically the stimulated Brillouin scattering (SBS) of an electromagnetic wave in non-dissipative
weakly magnetized plasma in the presence of dust particles with variable charge. 相似文献