Microwave Diagnostics of a Strong Arc Discharge Plasma in SF6

Abstract The paper deals with the microwave free-space diagnostics of high collision arc discharge plasmas. It is found that information about the electron density N and the collision frequency ν in such a plasma can be obtained from the energy transmitted through the plasma by an electromagnetic wave. The phase of the electromagnetic wave cannot be used since it is almost the same as that of a wave passing through vacuum. These basic concepts are verified experimentally at a frequency of 37.5 GHz. It is shown how the time dependence of the electron density in a plasma with constant and with time variable collision frequency may be evaluated.

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NONLINEAR DEMODULATION OF AN AMPLITUDE-MODULATED ELECTROMAGNETIC WAVE IN A PLASMA

Canadian Journal of Physics ◽

10.1139/p67-207 ◽

1967 ◽

Vol 45 (8) ◽

pp. 2543-2559 ◽

Cited By ~ 6

Author(s):

Sant Ram ◽

A. K. Arora

Keyword(s):

Electromagnetic Wave ◽

Electron Density ◽

Incident Wave ◽

Free Space ◽

Nonlinear Medium ◽

Dispersive Medium ◽

Collision Frequency ◽

Electric Vector

In this paper the authors have derived the expression for the electric vector when an amplitude-modulated electromagnetic wave propagates in a nonlinear dispersive medium. Demodulation is obtained in the case of a wave propagating in a nonlinear medium, whereas overmodulation has been obtained when the wave is reflected back in the free space from a plasma free-space interface. Some calculations have been performed in both cases and it has been found that the demodulation decreases with increasing electron density, with increasing index of modulation of the incident wave, and with increasing collision frequency. In the case of reflection the overmodulation is found to decrease with decreasing electron density, increasing index of modulation, and decreasing collision frequency inside the plasma. The calculated results have been presented in the form of tables in the Discussion.

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Novel nanocapsules with Co–TiC twin cores and regulable graphitic shells for superior electromagnetic wave absorption

RSC Advances ◽

10.1039/c8ra00040a ◽

2018 ◽

Vol 8 (12) ◽

pp. 6397-6405 ◽

Cited By ~ 16

Author(s):

Yuanliang Zhou ◽

Javid Muhammad ◽

Xuefeng Zhang ◽

Dongxing Wang ◽

Yuping Duan ◽

...

Keyword(s):

Electromagnetic Wave ◽

Discharge Plasma ◽

Arc Discharge ◽

Electromagnetic Wave Absorption ◽

Plasma Method ◽

Wave Absorption

Fabrication of Co–TiC@C nanocapsules via an arc discharge plasma method. Its optimum EM wave absorption was −66.59 dB at 8.76 GHz.

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Mikrowellenmessungen der Elektronendichte und -stoßfrequenz in elektromagnetisch erzeugten Stoßwellen

Zeitschrift für Naturforschung A ◽

10.1515/zna-1966-1206 ◽

1966 ◽

Vol 21 (12) ◽

pp. 2040-2046

Author(s):

W. Makios

Keyword(s):

Shock Front ◽

Electron Density ◽

Electron Density Distribution ◽

Discharge Plasma ◽

Collision Frequency ◽

Initial Pressure ◽

Electron Collision ◽

Microwave Measurements ◽

Electron Collision Frequency ◽

Microwave Transmission

Microwave measurements were made of the electron density and the electron collision frequency in the plasma between the shock front and the discharge plasma of electromagnetically produced shock waves. These investigations were carried out in argon and hydrogen at po=2 mm Hg initial pressure and velocities ranging from M=5 to M=20. At higher velocities the discharge plasma advances right into the shock front. A 4-mm-microwave transmission interferometer was used. A system of LECHER wires in the measuring arm of the interferometer provided a spatial resolution of approximately 1 to 2 mm and proved successful in measuring the electron density distribution between the shock front and the following discharge plasma. In the case of hydrogen the rise of the electron density in the shock front is caused by compression of the precursor electrons. In argon, on the other hand, most of the electrons are produced behind the shock front. A typical relaxation of the electron density towards equilibrium was measured. It was also possible to measure the electron collision frequency in argon as a function of time (and hence of the distance from the shock front).

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Measurements of the electron density and collision frequency of a one atmosphere uniform glow discharge plasma (OAUGDP/spl trade/) generated in a parallel plate reactor

The 30th International Conference on Plasma Science, 2003. ICOPS 2003. IEEE Conference Record - Abstracts. ◽

10.1109/plasma.2003.1228580 ◽

2003 ◽

Author(s):

Yunqiang Yang ◽

J.R. Roth ◽

M.K. Howlader

Keyword(s):

Glow Discharge ◽

Electron Density ◽

Parallel Plate ◽

Discharge Plasma ◽

Collision Frequency ◽

Glow Discharge Plasma ◽

Parallel Plate Reactor

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Measurements of Electron Density and Electron Temperature of Arc Discharge Plasmas Containing Metallic Vapors using Laser Thomson Scattering

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.133.458 ◽

2013 ◽

Vol 133 (9) ◽

pp. 458-464 ◽

Cited By ~ 3

Author(s):

Kentaro Tomita ◽

Shinya Yoshitake ◽

Kiichiro Uchino ◽

Daigo Takenaka ◽

Hiroaki Toda ◽

...

Keyword(s):

Electron Temperature ◽

Electron Density ◽

Arc Discharge ◽

Thomson Scattering ◽

Discharge Plasmas

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OPTICAL EMISSION SPECTROSCOPY OF CARBON ARC DISCHARGE PLASMA

Jurnal Teknologi ◽

10.11113/jt.v74.4735 ◽

2015 ◽

Vol 74 (8) ◽

Cited By ~ 1

Author(s):

Kashif Chaudhary ◽

Usman Tariq ◽

Sufi Roslan ◽

Ong Shude ◽

M. S. Aziz

Keyword(s):

Electron Temperature ◽

Electron Density ◽

Emission Spectroscopy ◽

Optical Emission Spectroscopy ◽

Discharge Plasma ◽

Arc Discharge ◽

Ambient Pressure ◽

Optical Emission ◽

Plasma Dynamics ◽

Arc Current

The arc discharge plasma is one of the efficient technique to fabricate nano-structures such as nanotubes, nanoparticles and thin films, which have variety of technological applications. In this study, plasma dynamics such as the electron density and temperature for arc discharge carbon plasma in methane ambient environment is presented to investigate the impact and contribution of physical parameter as arc current and ambient pressure on the plasma dynamics. The electron temperature and density is estimated applying in situ optical emission spectroscopy. The optical spectra are recorded for applied arc current 50A, 60A, 70A, 80A and 90A for ambient pressures 100torr, 300torr and 500torr. A rise in electron temperature and electron density is detected with increase in applied arc current and ambient pressure. The obtained results reveal that in arc discharge process, the arc current and ambient pressure have significant contribution towards the kinetics of the plasma species.

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