The Momentum Transfer Cross Section for Electrons in Argon in the Energy Range 0 - 4 eV

Milloy, HB; Crompton, RW; Rees, J A; Robertson, Andrew

doi:10.1071/ph770061

Cited by 197 publications

(64 citation statements)

References 4 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since n e values are for r = 0, we divided the value by 1.64 assuming a Bessel-like profile. For the value of C, we used R * = 3 mm, λ h = 0.0178 W(mK) −1 [26] and S heat = 6.7×10 −19 m 3 s −1 based on the work of references [27][28][29]. It can be seen that the agreement between theory and experiment is reasonable and falls in between the error bars.…”

Section: Discussionmentioning

confidence: 99%

Rayleigh scattering on a microwave surfatron plasma to obtain axial profiles of the atom density and temperature

Hübner

Iordanova

Palomares

et al. 2012

Eur. Phys. J. Appl. Phys.

View full text Add to dashboard Cite

Please check the document version of this publication:• A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. Abstract. The axial dependency of the central-axis value of the heavy particle density and temperature of surface-wave plasmas is studied using Rayleigh scattering (RyS). The plasma is generated at a frequency of 2.45 GHz in argon by a surfatron operating under the standard settings of a power of 45 W, a flow rate of 50 sccm and a pressure of 20 mbar. To investigate the effect of the pressure on the gas temperature, we also investigated 6 and 10 mbar plasmas. By using a two-dimensional intensified CCD array we could determine and eliminate the influence of false stray light, a major disturbing factor in the determination of the Rayleigh signal. In order to trace the energy fluxes that determine the gas temperature, we performed Thomson scattering so that the properties of the electron gas are known. It is found that the gas temperature, T a, depends on the wall temperature and the product of the gas pressure and the electron pressure. The latter implies that Ta follows the electron density axially, meaning that it is highest at the launcher and decreases monotonically in the wave propagation direction. The maximum gas temperature of around Ta = 800 K is found close to the launcher for the highest gas pressure of 20 mbar. For lower pressures we find lower Ta values. The extrapolation of Ta toward the end of the plasma column leads to a temperature of about 320 K. This study reveals that, for the argon plasmas under study, the central-axis values of the gas temperature are determined by the balance between the heating of the gas by means of elastic electron collisions and the cooling due to heat conduction from the center to the wall.

show abstract

Section: Discussionmentioning

confidence: 99%

Rayleigh scattering on a microwave surfatron plasma to obtain axial profiles of the atom density and temperature

Hübner

Iordanova

Palomares

et al. 2012

Eur. Phys. J. Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…This paper reports data for the ratio of the lateral diffusion coefficient to mobility (DTIJl) at 294 K over a range of EIN (E being the electric field strength and N the gas number density) from 0·001 to 0·1 Td. In the following companion paper (Milloy et al1977; present issue p. 61) these data, together with the data for the electron drift velocity reported in the previous paper (Robertson 1977;p. 39) are used to determine qm(e) for electrons in argon in the energy range from 0 to 4 eV.…”

Section: Introductionmentioning

confidence: 63%

“…2. To help understand the relationship between DTI ft and the form of the momentum transfer cross section, the mean electron energy ii, calculated using the cross section of Milloy et al (1977), is also plotted in Fig. 2.…”

Section: Resultsmentioning

confidence: 99%

“…The data plotted in Fig. 6 of Milloy et al (1977) were used for evaluating this term. 0·3395 0·0080 0·4283 0·4295 0·4295 0·4314 0·4311 0·4323 0·4304 0·010 0·5012 0·5059 0·5074 0·5069 0'5069 0·5075 0·5060 0·012 0·5656 0·5701 0·5713 0·5719 0·5714 0·5726 0·5705 0·014 0·6265 0·6264 0·6283 0·6291 0·6295 0·6302 0·6283 0·017 0·6979 0·7017 0·7038 0·7036 0'7040 0·7049 0·7027 0·020 0·7613 0·7625 0·7650 0·7682 0·7689 0·7695 0'7659 0·025 0·8507 0·8545 0'8574 0·8593 0·8611 0·8617 0·8575 0·030 0·9293 0·9342 0·9371 0·9380 0·9387 0·9355 0·035 0·9962 1·003 1·006 1·005 1'003 0·040 1·054 1·060 1·064 1'064 1·061 0·050 1·159 1·162 1'167 1·163 0·060 1·245 1·250 1·248 0·080 1·391 1·391 0·100 1'508 1·508…”

Section: A = W/2dt •mentioning

confidence: 99%

“…In the case of argon, however, there is considerable doubt about the magnitude of the cross section, particularly in the region of the Ramsauer minimum. The cross section derived by Frost and Phelps (1964) from an analysis of the mobility data of Pack et al (1962) and the lateral diffusion data of Warren and Parker (1962) differs at energies near the minimum by as much as a factor of five from the cross section derived by Golden (1966) using atomic effective-range theory to analyse total cross section measurements at energies in the range 0·1-21·6 eV (Golden and Bandel 1966).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Ratio of the Lateral Diffusion Coefficient to Mobility for Electrons in Argon at 294 K

Milloy¹,

Crompton²

1977

Aust. J. Phys.

Self Cite

View full text Add to dashboard Cite

The ratio of the lateral diffusion coefficient to mobility (DT/P,) for electrons in argon has been measured at 294 K in the range 0'001 ,,;;; E/N (Td) ,,;;; 0·1 using pressures in the range 309-1171 kPa.The total error in the best-estimate values is estimated to be less than ± 2 % for E/ N ,,;;; 0·0035 Td and less than ± 1 . 5 % for E/ N ;:;, o· 004 Td. A discussion is given of the design of a TownsendHuxley diffusion experiment in light of recent theoretical work on the influence of material boundaries on diffusing streams of charged particles and of the effects on the measurements of multiple scattering and dimer formation.

show abstract

Kinetics of the Ar‐Hg Plasma of Fluorescent Lamp Discharges. I. Model — Basic Equations — Hg Partial Pressure Variation

Wilhelm

Winkler

1983

Annalen der Physik

View full text Add to dashboard Cite

A b s t r a c t . A kinetic description of the dc Hg-Ar mixture plasma of fluorescent lamp discharges is given on the basis of the main microphysical processes and corresponding atomic data. The investigation comprises particle balances for the excited Hg atoms of the triplet 63P0,,,, and singulet GlP, state, the balance of the discharge current and an adequate form of the electron Boltzmann equation for such a mixture plasma, the latter including also the various binary collision processes with excited Hg atoms and the Coulomb interaction between the electrons. By simultaneously solving the balances together with the kinetic equation the densities of electrons and excited Hg atoms, the electron energy distribution, the resulting mean energy, mobility and various energy transfer rates of the electrons and the ultraviolet radiation output were determined and in part compared with measured data from the literature. This paper presents and analyses the macroscopic plasma properties mentioned for a wide range of the wall temperature or the corresponding Hg partial pressure variation, where a good agreement of calculated results with experimental data is obtained. I n a second paper the change of the macroscopic plasma behaviour due to variation of buffer gas pressure and discharge current will be dealt with. Kinetik des Ar-Hg-Plasmas von LeuchtstofflampenentladungenI. Model1 -Grundgleichungen -Hg-Partialdruckvariation I n h a l t s u b e r s i c h t . Die Arbeit befafit sich auf der Qrundlage der wesentlichen mikrophysikalischen Prozesse und der entsprechenden atomaren Daten niit der kinetischen Beschreibung des dc Hg-Ar-Mischplasmas von Leuchtstofflampencntladungen. Die Untersuchung verwendet die Teilchenbilanzen fur die angeregten Hg-Atonie des Tripletts 63P0,,,2 und des Singuletts @PI, die Bilanz fur den Entladungsstrom iind eine adaquate Form der Elektronen-Boltzmann-Gleichung fur ein solches Mischplasma, wobei in letzterer auch die verschiedenen ZweierstoBprozesse mit angeregten Hg-Atomen und die Coulomb-Wechselwirkung zwischen den Elektronen berucksichtigt wird. Mittels simultaner Losung der Bilanzgleichungen zusammen mit der kinetischen Gleichung wurden sowohl die Dichten der Elektronen und angercgten Hg-Atome, die Elektronenenergieverteilung, die sich ergebende mittlere Energie, Beweglichkeit rind die verschiedenen Energieubertragungsraten der Elektronen als auch die Ausbeute a n ultravioletter Strahlung bcstimmt und teilweise mit in der Literatur verfugbaren MeRdaten verglichen. In dieser Arbeit werden die genannten makroskopischen Plasmaeigenschaften fur einen weiten Variationsbereich der Wandtemperatur und damit des Hg-Partialdruckes dargestellt und analysiert, wobei gute Ubereinstimmung von berechneten iind experimentellen Ergebnissen erhalten wird. In einer weiteren Arbeit wird das makroskopische Plasmaverhalten bei Variation des Puffergasdruckes iind des Entladungsstromes dargestellt iind diskutiert.

show abstract

The Momentum Transfer Cross Section for Electrons in Argon in the Energy Range 0 - 4 eV

Cited by 197 publications

References 4 publications

Rayleigh scattering on a microwave surfatron plasma to obtain axial profiles of the atom density and temperature

Rayleigh scattering on a microwave surfatron plasma to obtain axial profiles of the atom density and temperature

The Ratio of the Lateral Diffusion Coefficient to Mobility for Electrons in Argon at 294 K

Kinetics of the Ar‐Hg Plasma of Fluorescent Lamp Discharges. I. Model — Basic Equations — Hg Partial Pressure Variation

Contact Info

Product

Resources

About