Stationary Velocity and Charge Distributions of Grains in Dusty Plasmas

Abstract

Within the kinetic approach velocity and charge distributions of grains in stationary dusty plasmas are calculated and the relations between the effective temperatures of such distributions and plasma parameters are established. It is found that the effective temperature which determines the velocity grain distribution could be anomalously large due to the action of accelerating ionic bombarding force. The possibility to apply the results obtained to the explanation of the increasing grain temperature in the course of the Coulomb-crystal melting by reduction of the gas pressure is discussed. This paper was received by Phys.Rev.Lett. on 11 August 1999. As potential referees the authors offered to Editor the following persons: V.N.Tsytovich, Russia; R.Bingham, UK; D.Resendes, Portugal; G.Morfill, P.Shukla, Y.M.Yu., Germany.Comment: 8 pages, no figure

Response to “Comment on ‘Ion collection by a sphere in a flowing collisional plasma’” [Phys. Plasmas 14, 074701 (2007)]

“…The results obtained within this simple model can be instructive in understanding the reason of the sign reversal of the ion drag force in complex plasmas discussed recently in the literature. [4][5][6][7] The identified mechanism responsible for this effect is a rarefaction of the ion density downstream from the sphere due to ion absorption. However, the model is apparently too simplified to be used for the ion drag force estimates in practical complex plasmas.…”

Brownian particle in non-equilibrium plasma

“…The appropriate calculations for the case of collisionless plasma were obtained in [14,15] on the basis of the microscopic treatment. In the case of the grain moving in weakly-ionized plasma the basic set of equations for individual component concentration variations can be written in the form [1,2] ∂n α (r, t) ∂t − divΓ α = I 0 − βn e r, t)n i r, t) − S α δ(r − vt) (18) and the Poisson equation for the potential is given by…”

Rotational kinetics of absorbing dust grains in neutral gas

“…The kinetic description of dusty plasma was discussed in numerous theoretical studies [3,4,5,6,7,8,9]. Generally, there are two ways plasma particles interact with dust grains: first, the scattering of a particle by grain electric field and, second, the direct impact of a particle on a grain surface.…”

“…In other words, as it is well-understood nowadays, the adequate statistical description of the dust component should take into account inner degrees of freedom, the most important among which is the grain charge. Kinetic consideration of charging process shows that absorption of small plasma particles by grains can result in inequality of the grain temperature and the temperatures of the light components even for the case of equal temperatures of electrons and ions [3,4].…”