Anomalous Diffusion at Edge and Core of a Magnetized Cold Plasma

Progress in the theory of anomalous diffusion in weakly turbulent cold magnetized plasmas is explained. Several proposed models advanced in the literature are discussed. Emphasis is put on a new proposed mechanism for anomalous diffusion transport mechanism based on the coupled action of conductive walls (excluding electrodes) bounding the plasma drain current (edge diffusion) together with the magnetic field flux "cutting" the area traced by the charged particles in their orbital motion. The same reasoning is shown to apply to the plasma core anomalous diffusion. The proposed mechanism is expected to be valid in regimes when plasma diffusion scales as Bohm diffusion and at high $B/N$, when collisions are of secondary importance.Comment: 9 pages, 4 figure

Influence of excited molecules on electron swarm transport coefficients and gas discharge kinetics

In this paper we study different effects of excited molecules on swarm parameters, electron energy distribution functions and gas discharge modeling. First we discuss a possible experiment in parahydrogen to resolve the discrepancy in hydrogen vibrational excitation cross section data. Negative differential conductivity (NDC) is a kinetic phenomenon which manifests itself in a particular dependence of the drift velocity on E/N and it is affected by superelastic collisions with excited states. A complete kinetic scheme for argon required to model excited state densities in gas discharges is also described. These results are used to explain experiments in capacitively and inductively coupled RF plasmas used for processing. The paper illustrates the application of atomic and molecular collision data, swarm data and the theoretical techniques in modeling of gas discharges with large abundances of excited molecules. It is pointed out that swarm experiments with excited molecules are lacking and that there is a shortage of reliable data, while the numerical procedures are sufficiently developed to include all the important effects

Mobility of positive ions in CF4

Cross-section sets for transport of positive ions in CF4 that fit the available experimental data for mobility are assessed by normalizing the available experimental and theoretical cross-sections within the framework of the swarm method. Transport parameters for positive ions in CF4 in DC fields at a gas temperature of T = 300 K are calculated as a function of the reduced electric fields E/N (N being the gas density) by using Monte Carlo simulation

Mobility of positive ions in CF4

Cross-section sets for transport of positive ions in CF4 that fit the available experimental data for mobility are assessed by normalizing the available experimental and theoretical cross-sections within the framework of the swarm method. Transport parameters for positive ions in CF4 in DC fields at a gas temperature of T = 300 K are calculated as a function of the reduced electric fields E/N (N being the gas density) by using Monte Carlo simulation

Rate coefficients for

In this paper, we present most probable reactions of $$\hbox {Ar}^{{+}}$$ ion with $$\hbox {Ar/BF}_{{3}}$$ mixtures. Appropriate gas phase enthalpies of formation for the products were used to calculate scattering cross section as a function of kinetic energy. These data are needed for modeling in numerous applications of technologically important $$\hbox {BF}_{{3}}$$ discharges. Results for transport parameters, specially rate coefficients as a function of E/N (E-electric field; N-gas density) were obtained by using the Monte Carlo technique

H⁺ Scattering in n-Butanol

In this paper we show predictions for the low energy cross-sections and transport properties for the H⁺ in n-butanol gas. These data are needed for modelling in numerous technologically important applications. Appropriate gas phase enthalpies of formation for the products were used to calculate scattering cross-section as a function of kinetic energy. Calculated cross-sections can be used to obtain transport parameters as a function of E/N (E - electric field, N - gas density) for H⁺ in n-butanol gas

Rate Coefficients of F−F^{-} Ions in Ar//BF3Ar//BF_{3} Mixtures

Transport parameters of $F^{-}$ ions in mixtures $Ar//BF_{3}$ in DC fields were calculated using Monte Carlo simulation technique assuming the scattering cross-section set assembled on the basis of Nanbu's technique separating elastic from reactive collisions. In this work we present characteristic energy and rate coefficients for low and moderate reduced electric fields E/N (N - gas density) and account for the non-conservative collisions

Effect of exothermic reactions on the mobility of Ar

In this letter we present a cross-section set and transport properties for Ar+ scattering on CF4 for relative energies up to 1000 eV. Monte Carlo simulation method is applied to accurately calculate transport parameters in hydrodynamic regime. We present new data for Ar+ ions in CF4 as a function of reduced electric fields E/N (N-gas density) where the gas temperature $T_{\text{g}}$ is used as a parameter. Values of the reduced mobility are discussed. Discrepancy of reduced mobility for $T_{\text{g}}\rightarrow0$ and $E\rightarrow0$ from the polarization limit was previously theoretically considered but rarely measured especially in the presence of exothermic reactions. We find that internally resonant exothermic dissociative charge transfer cross-section for $\text{CF}_{3}^{+}$ production significantly increases zero-field ion mobility with respect to the polarization limit

Cross-section and transport parameters of Ne⁺ in CF₄

A cross-section set for scattering Ne⁺ ions in CF₄ is assessed by using available experimental data for charge transfer cross-sections. In this paper we present new results for the mean energy, reduced mobility and diffusion coefficients for low and moderate reduced electric fields E/N (N - gas density) and account for the non-conservative collisions. The Monte Carlo method is used to calculate transport properties of Ne⁺ ions in CF₄ at temperature of T=300 K

Solving the RWA Problem in WDM Optical Networks Using the BCO Meta-Heuristic

This paper researches the routing and wavelength assignment (RWA) problem in wavelength routed optical WDM networks with the wavelength conversion capability at different network nodes. We studied the static case in which all connection requests are known in advance, thus a routing decision can be made based on the complete knowledge of the traffic to be served by the network. The Bee Colony Optimization (BCO) metaheuristic is applied to solve the RWA problem. We carried out a comprehensive simulation study of the performance of the proposed BCORWA algorithm for different network topologies and traffic scenarios. The obtained simulation results are analyzed and compared