Radiale Änderungen der Energieverteilungsfunktion der Elektronen im Plasma der positiven Säule elektrischer Entladungen

Herrmann, D.; Rutscher, A.; Pfau, S.

doi:10.1002/ctpp.19710110107

Cited by 27 publications

(5 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results of the electron-distribution-function measurements under low and high pressures along the radius of the discharge tube reveal various features which are well explained by the considerations of electron kinetics by kinetic and diffusion theories. For instance, measurements of the radial potential and EDFs with the help of a Langmuir probe in low-pressure discharges [19][20][21][22] convincingly demonstrate that the total energy is in fact the argument of the distribution function. Measurements of the EDF at pressures of tens of Torr with the help of a probe in the diffusion regime under conditions of the fulfillment of the premises of diffusion theory show that the EDF can be represented as the product of the radially dependent electron density and the distribution function dependent on the kinetic energy and independent of the radial coordinate [22].…”

Section: A Comparison With Results Of Experimentsmentioning

confidence: 99%

A comparison of kinetic and fluid models of the positive column of discharges in inert gases

Golubovskiǐ

Porokhova

Behnke

1999

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The models of a positive column of an inert gas discharge at low pressures and small currents are developed in the frameworks of nonlocal kinetic and local fluid theories. Both models are based on the joint solution of the corresponding kinetic equation, ion-motion equation and Poisson equation that permit one to describe bulk plasma and near-wall sheaths of space charge. The theories differ principally in the descriptions of the electron component of a plasma. In the fluid theory the radial flux of electrons is a combination of field and diffusive fluxes, but in the kinetic model a similar representation is impossible. A comparison of the distribution functions and macroscopic properties calculated by kinetic and fluid theories for the discharge under the same conditions is performed. This comparison is carried out for the models of the positive column developed under the assumption of plasma quasi-neutrality and with regard to the deviations from quasi-neutrality. The use of the fluid theory beyond its application range (low pressures and small currents) does not reflect the physical picture of discharge sustenance and leads to incorrect results with respect to several parameters.

show abstract

Section: A Comparison With Results Of Experimentsmentioning

confidence: 99%

A comparison of kinetic and fluid models of the positive column of discharges in inert gases

Golubovskiǐ

Porokhova

Behnke

1999

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…For a recent review about these distributions, the reader is referred to [80], and the original works can be found in Refs. [81,82,83] We present two examples. The first example is shown in Table 4, and depicts the fitted plasma parameters with different V * starting from all the experimental data up to V * = V f .…”

Section: Discussionmentioning

confidence: 99%

New procedure to estimate plasma parameters through the q-Weibull distribution by using a Langmuir probe in a cold plasma

Gonzalez

González

Soler

et al. 2022

Plasma Res. Express

View full text Add to dashboard Cite

We describe a procedure to obtain the plasma parameters from the {\bf I-V} Langmuir curve by using the Druyvesteyn equation. We propose to include two new parameters, $q$ and $r$, to the usual plasma parameters: plasma potential ($V_p$), floating potential ($V_f$), electron density ($n$), and electron temperature ($T$). These new parameters can be particularly useful to represent non-Maxwellian distributions. The procedure is based on the fit of the {\bf I-V} Langmuir curve with the $q$-Weibull distribution function, and is motivated by recent works which use the $q$-exponential distribution function derived from Tsallis statistics. We obtain the usual plasma parameters employing three techniques: the numerical differentiation using Savitzky Golay (SG) filters, the $q$-exponential distribution function, and the $q$-Weibull distribution function. We explain the limitations of the $q$-exponential function, where the experimental data $V>V_p$ needs to be trimmed beforehand, and this results in a lower accuracy compared to the numerical differentiation with SG. To overcome this difficulty, the $q$-Weibull function is introduced as a natural generalization to the $q$-exponential distribution, and it has greater flexibility in order to represent the concavity change around $V_p$. We apply this procedure to analyze the measurements corresponding to a nitrogen $N_2$ cold plasma obtained by using a single Langmuir probe located at different heights from the cathode. We show that the $q$ parameter has a very stable numerical value with the height. This work may contribute to clarify some advantages and limitations of the use of non-extensive statistics in plasma diagnostics, but the physical interpretation of the non-extensive parameters in plasma physics remains not fully clarified, and requires further research.

show abstract

“…The second derivative of the probe current with respect to the probe potential gives the EEDF f (W ), as follows [11,[15][16][17]:…”

Section: Gas Supplier Vaccum Systemmentioning

confidence: 99%

Electron energy distribution function in the positive column of a neon glow discharge using the black wall approximation

Al‐Hawat

Naddaf

2005

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The electron energy distribution function (EEDF) was determined from the second derivative of the I–V Langmuir probe characteristics and, thereafter, theoretically calculated by solving the plasma kinetic equation, using the black wall (BW) approximation, in the positive column of a neon glow discharge. The pressure has been varied from 0.5 to 4 Torr and the current from 10 to 30 mA.The measured electron temperature, density and electric field strength were used as input data for solving the kinetic equation.Comparisons were made between the EEDFs obtained from experiment, the BW approach, the Maxwellian distribution and the Rutcher solution of the kinetic equation in the elastic energy range. The best conditions for the BW approach are found to be under the discharge conditions: current density jd = 4.45 mA cm−2 and normalized electric field strength E/p = 1.88 V cm−1 Torr−1.

show abstract

Radiale Änderungen der Energieverteilungsfunktion der Elektronen im Plasma der positiven Säule elektrischer Entladungen

Cited by 27 publications

References 16 publications

A comparison of kinetic and fluid models of the positive column of discharges in inert gases

A comparison of kinetic and fluid models of the positive column of discharges in inert gases

New procedure to estimate plasma parameters through the q-Weibull distribution by using a Langmuir probe in a cold plasma

Electron energy distribution function in the positive column of a neon glow discharge using the black wall approximation

Contact Info

Product

Resources

About