Results 221 to 230 of about 1,437,991 (290)

High Impedance Langmuir Probes

Review of Scientific Instruments, 1968
The operating characteristics and limitations of high impedance resistive probes are discussed. A new high impedance probe employing capacitive coupling to detect plasma floating potential is described. The advantages of capacitive coupling for increasing the input impedance, reducing the size, and broadening the bandwidth are illustrated.
openaire   +1 more source

New Applications of Langmuir Probes

Physics of Atomic Nuclei, 2017
In this work, two new possibilities for standard probe diagnostics are described. The first one can be used to study isotropic, collisionless low-pressure plasma in which the electron energy distribution function is close to a Maxwellian one. In such plasmas, the Boltzmann law, Bohm effect, and 3/2 power law are valid.
P. E. Masherov, A. F. Piskunkov, V. A. Riaby, V. P. Savinov, V. G. Yakunin   +4 more
openaire   +1 more source

HIGH ALTITUDE GUN PROBES (DEVELOPMENT OF LANGMUIR PROBES)

1965
Abstract : This final report describes a program to develop an instrument capable of measuring electron density in the 50 to 160 kilometer altitude region and capable of surviving a 60,000 'G' shock encountered during launch from a cannon. This report is in two parts: The first describes various techniques and instruments capable of measuring electron ...
L. C. Smith, A. L. Kadis, A. V. Block
openaire   +1 more source

Automatic Langmuir probe plasma diagnostic

Review of Scientific Instruments, 1987
The hardware implementation of a computer-based Langmuir probe technique is described. The technique, which is applicable in a wide range of dc plasma conditions, allows a full range of plasma parameters to be measured efficiently.
Hopkins, M.B., Graham, Bill, Griffin, T.J.   +2 more
openaire   +1 more source

Validating cylindrical Langmuir probe techniques

Review of Scientific Instruments, 1992
Several methods for estimating the plasma potential and density using cylindrical Langmuir probes are compared to the self-consistent solutions of the Vlasov–Poisson equations calculated by Laframboise (J. G. Laframboise, Ph. D. dissertation, University of Toronto, 1966).
J. H. Rogers, J. S. De Groot, D. Q. Hwang   +2 more
openaire   +1 more source

Langmuir-probe measurements in flowing-afterglow plasmas

Physical Review E, 1994
The validity of the orbital-motion theory for cylindrical Langmuir probes immersed in flowing-afterglow plasmas is investigated experimentally. It is found that the probe currents scale linearly with probe area only for electron-collecting but not for ion-collecting probes.
, Johnsen, , Shun'ko, , Gougousi, , Golde   +3 more
openaire   +2 more sources

EXPERIMENTAL INVESTIGATION OF LANGMUIR PROBES

Canadian Journal of Physics, 1967
Electron temperatures and densities measured in a weakly ionized helium afterglow with cylindrical double probes are compared with measurements obtained using a gated microwave radiometer and a microwave resonant cavity. The pressure was varied from 0.1 to 8.5 Torr. At low pressure, magnetic fields up to 0.11 T were applied.
R. M. Clements, H. M. Skarsgard
openaire   +1 more source

Ion‐Neutral Collision Effects in Langmuir Probe Theory

Contributions to Plasma Physics, 2008
AbstractIn weakly collisional sheaths, potential wells and barriers could appear. These can cause the presence of repulsed and trapped ions in the region surrounding a negatively biased Langmuir probe, invalidating the orbital motion limited (OML) theory. In this work, a Particle‐In‐Cell/Test‐Particle Monte Carlo (PIC/TPMC) model of Ar plasma at medium
F Taccogna, S Longo, M Capitelli
openaire   +4 more sources

Langmuir probes and ion flow

Journal of Physics D: Applied Physics, 1970
Plane probes have been used to measure plasma density in the positive column of a low pressure mercury discharge. The results have been found to depend on the orientation of the probe face and it is suggested that this is due to the effects of radial ion flow. It is shown that accurate values for plasma density distribution can be obtained by placing a
openaire   +1 more source

Langmuir probes for plasma plume diagnostics

2014 IEEE 41st International Conference on Plasma Sciences (ICOPS) held with 2014 IEEE International Conference on High-Power Particle Beams (BEAMS), 2014
Langmuir probes are highly versatile plasma diagnostic tools. Triple Langmuir probes (TLP) can be used to measure electron the temperature (T e ) and density (n e ) with time resolution. This ability gives a unique opportunity to observe the time evolution of discontinuities formed at the interaction of a plasma flow with a static background plasma ...
A. Arias, N. Quiros, R. Presura
openaire   +1 more source