Effects of Electron Temperature Fluctuation on Turbulence Measurement by Langmuir Probe in a Magnetized Helicon Plasma

Low-pressure capacitively coupled RF discharge Ar plasma has been studied using Langmuir probe. The electron temperature, electron density and Debay length were calculated under different pressures and electrode gap. In this work the RF Langmuir probe is designed using 4MHz filter as compensation circuit and I-V probe characteristic have been investigated. The pressure varied from 0.07 mbar to 0.1 mbar while electrode gap varied from 2-5 cm. The plasma was generated using power supply at 4MHz frequency with power 300 W. The flowmeter is used to control Argon gas flow in the range of 600 standard cubic centimeters per minute (sccm). The electron temperature drops slowly with pressure and it's gradually decreased when expanding the electrode gap. As the gas pressure increases, the plasma density rises slightly at low gas pressure while it drops little at higher gas pressure. The electron density decreases rapidly with expand distances between electrodes.

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Electron temperature in nighttime sporadic E layer at mid-latitude

Annales Geophysicae ◽

10.5194/angeo-26-533-2008 ◽

2008 ◽

Vol 26 (3) ◽

pp. 533-541 ◽

Cited By ~ 8

Author(s):

K.-I. Oyama ◽

T. Abe ◽

H. Mori ◽

J. Y. Liu

Keyword(s):

Heat Source ◽

Electron Temperature ◽

Physical Parameter ◽

Langmuir Probe ◽

Present Theory ◽

Height Range ◽

Neutral Temperature ◽

Sporadic E Layer ◽

Sporadic E ◽

Parameter Values

Abstract. Electron temperature in the sporadic E layer was measured with a glass-sealed Langmuir probe at a mid-latitude station in Japan in the framework of the SEEK (Sporadic E Experiment over Kyushu)-2 campaign which was conducted in August 2002. Important findings are two fold: (1) electron temperature and electron density vary in the opposite sense in the height range of 100–108 km, and electron temperature in the Es layer is lower than that of ambient plasma, (2) electron temperature in these height ranges is higher than the possible range of neutral temperature. These findings strongly suggest that the heat source that elevates electron temperature much higher than possible neutral temperature exists at around 100 km, and/or that the physical parameter values, which are used in the present theory to calculate electron temperature, are not proper.

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A FULLY AUTOMATIC CONTINUOUS ELECTRON TEMPERATURE MEASUREMENT SYSTEM USING A DOUBLE LANGMUIR PROBE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19797406 ◽

1979 ◽

Vol 40 (C7) ◽

pp. C7-841-C7-842 ◽

Cited By ~ 4

Author(s):

T. N. Todd

Keyword(s):

Electron Temperature ◽

Temperature Measurement ◽

Measurement System ◽

Langmuir Probe ◽

Fully Automatic ◽

Temperature Measurement System

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Temperature and Lifetime Measurements in the SSX Wind Tunnel

Plasma ◽

10.3390/plasma1020020 ◽

2018 ◽

Vol 1 (2) ◽

pp. 229-241 ◽

Cited By ~ 4

Author(s):

Manjit Kaur ◽

Kaitlin Gelber ◽

Adam Light ◽

Michael Brown

Keyword(s):

Simple Model ◽

Wind Tunnel ◽

Electron Temperature ◽

Langmuir Probe ◽

Vacuum Ultraviolet ◽

Lifetime Measurements ◽

Line Intensities ◽

Thermal Equilibration ◽

Local Measurements ◽

Doppler Spectroscopy

We describe ion and electron temperature measurements in the Swarthmore Spheromak Experiment (SSX) MHD wind tunnel with the goal of understanding limitations on the lifetime of our Taylor-state plasma. A simple model based on the equilibrium eigenvalue and Spitzer resistivity predicted the lifetime satisfactorily during the first phase of the plasma evolution. We measured an average T e along a chord by taking the ratio of the C I I I 97.7 nm to C I V 155 nm line intensities using a vacuum ultraviolet (VUV) monochromator. We also recorded local measurements of T e and n e using a double Langmuir probe in order to inform our interpretation of the VUV data. Our results indicated that the plasma decayed inductively during a large part of the evolution. Ion Doppler spectroscopy measurements suggested that ions cooled more slowly than would be expected from thermal equilibration with the electrons, which maintained a constant temperature throughout the lifetime of the plasma.

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New algorithms to estimate electron temperature and electron density with contaminated DC Langmuir probe onboard CubeSat

Advances in Space Research ◽

10.1016/j.asr.2019.11.025 ◽

2020 ◽

Vol 66 (1) ◽

pp. 148-161

Author(s):

Shyh-Biau Jiang ◽

Tse-Liang Yeh ◽

Jann-Yenq Liu ◽

Chi-Kuang Chao ◽

Loren C. Chang ◽

...

Keyword(s):

Electron Temperature ◽

Electron Density ◽

Langmuir Probe ◽

New Algorithms

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Electron temperature fluctuation measurements and techniques in the DIII-D tokamak

Review of Scientific Instruments ◽

10.1063/1.1147613 ◽

1997 ◽

Vol 68 (1) ◽

pp. 484-487 ◽

Cited By ~ 8

Author(s):

C. L. Rettig ◽

W. A. Peebles ◽

J. Lohr ◽

M. E. Austin

Keyword(s):

Electron Temperature ◽

Temperature Fluctuation

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Study on the Plume Characteristics of Pulsed Plasma Thruster

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.55 ◽

2013 ◽

Vol 347-350 ◽

pp. 55-58

Author(s):

Yong Li ◽

Rui Zhang ◽

Jian Hua Zong

Keyword(s):

Electron Temperature ◽

Langmuir Probe ◽

Current Model ◽

Energy Levels ◽

Pulsed Plasma ◽

Discharge Energy ◽

Pulsed Plasma Thruster ◽

Plasma Thruster ◽

A Current ◽

Date Processing

A current-model Triple Langmuir probe was developed and used to measure electron temperature and density of the Pulsed Plasma Thruster plume. To decreasing the errors in measurement, Probe, collection circuit and glow cleaning devices were elaborately designed. A FIR digital Filter based on Matlab was designed and the software for date processing was developed by Labview. Measurements were taken at various position in the plume of a Pulsed Plasma Thruster operating at discharge energy of 6-24J. The results show the thruster plume has electron temperatures in the range between 0.6and 5.4eV, electron densities between 0.9×1019 and 4.1x1021m-3 for all discharge energy levels considered. Electron temperature and density decrease with increasing angle away from the centerline and with decreasing discharge energy.

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