Bohm criterion in dusty plasmas with two species of positive ions and non-thermal electrons

Abstract

Bohm criterion is revisited in the framework of a one-dimensional stationary and unmagnetized low-pressure argon and helium plasma mixture containing non-thermal electrons and dust grains model. Dust grains, electron non-thermality, and ions density ratio effects on Bohm velocities along with dust grain charge number |Φd0|, are investigated. It is revealed that Bohm velocities are highly correlated, with their profiles exhibiting a moving peak. Mixing the two gases allowed the appearance of subsonic (argon) as well as supersonic (helium) Bohm velocities. The present model may be generalized to many ion species plasmas.

Numerical study of an electrostatic plasma sheath with non‐thermal electrons and charged nanoparticles

“…[15][16][17][18][19][20] At low-pressure discharges, the electron energy distribution departs significantly from the Maxwellian distribution and represents a non-thermal distribution. [39] Recently, the Bohm criterion in dusty plasmas with two species of positive ions and non-thermal electrons with Cairns distribution was studied by Fouial et al [40] In the present work, we study the effects of non-thermal electrons on the sheath width and the spatial profiles of the electrostatic potential, electron density, and the number densities and velocities of the ions and dust particles. This heating is due to interaction of electrons with moving sheath edge.…”

“…In recent years, this type of distribution function has been employed to investigate some basic physical characteristics of the plasmas such as dust acoustic waves, [31][32][33][34] ion acoustic waves, [35] magnetized electron-positron-ion plasma, [36] laser-created plasma, [37] electron acoustic solitary waves, [38] and dust charging. [39] Recently, the Bohm criterion in dusty plasmas with two species of positive ions and non-thermal electrons with Cairns distribution was studied by Fouial et al [40] In the present work, we study the effects of non-thermal electrons on the sheath width and the spatial profiles of the electrostatic potential, electron density, and the number densities and velocities of the ions and dust particles. Using Cairns distribution for non-thermal electrons, the charge of dust particles is calculated and its effects on the sheath dynamics are investigated.…”

“…[42] Where r d is the dust radius and d is the potential on the dust surface relative to the plasma potential. [40,42] [40,42] …”

Effects of non‐extensive electrons on the sheath of dusty plasmas with variable dust charge

“…It can be found in various technological devices, such as the device for plasma‐assisted material and plasma nanofabrication, plasma discharges, and plasma medicine, as well as controlled fusion devices . Most of the research articles discussed the effect of parameters that can modify the sheath characteristics in dusty plasmas, for example the action of an external magnetic field, the collisions force, the multi‐species of positive or/and negative ions, the two electron temperature, the dust charge variation, and the size of dust grains . In all of these investigations mentioned above, the electron distribution has been assumed to be Maxwellian (i.e., which is based on the Boltzmann‐Gibbs [BG] statistics).…”

Numerical Computation of the Electrostatic Sheath Thickness

“…This type of interaction is widely used in many areas of laboratory, industrial and astrophysical plasmas. Indeed, several researchers have investigated analytically and experimentally this subject [1][2][3][4][5][6][7][8][9][10]. This interaction gives rise to non-neutral region, called electrostatic sheath, in which a strong localized electric field occurs.…”