Plasma Parameters

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Plasma parametersFrom Wikipedia, the free encyclopedia

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The complex self-constricting magnetic field lines and current paths in a Birkeland current

that may develop in a plasma (Evolution of the Solar System, 1976)

Plasma parameters define various characteristics of aplasma, an electrically conductive

collection ofcharged particles that responds collectively to electromagnetic forces. Plasma

typically takes the form of neutral gas-like clouds or charged ion beams, but may also include

dust and grains.[1] The behaviour of such particle systems can be studied statistically. [2]

Contents 1 Fundamental plasma parameters

o 1.1 Frequencies

o 1.2 Lengths

o 1.3 Velocities

o 1.4 Dimensionless

2 See also

3 References

4 Footnotes

Fundamental plasma parameters
https://en.wikipedia.org/wiki/Birkeland_currenthttps://en.wikipedia.org/wiki/Plasma_(physics)https://en.wikipedia.org/wiki/Charged_particlehttps://en.wikipedia.org/wiki/Electromagnetic_forcehttps://en.wikipedia.org/wiki/Ion_beamhttps://en.wikipedia.org/wiki/Birkeland_currenthttps://en.wikipedia.org/wiki/Plasma_(physics)https://en.wikipedia.org/wiki/Charged_particlehttps://en.wikipedia.org/wiki/Electromagnetic_forcehttps://en.wikipedia.org/wiki/Ion_beam


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All quantities are in Gaussian (cgs) units except temperature expressed in eV and ion mass

expressed in units of theproton mass ;Zis charge state; kisBoltzmann's

constant;Kis wavenumber; is the adiabatic index; ln is the Coulomb logarithm.

Frequencies

electron gyrofrequency, the angular frequency of the circular motion of an electron inthe plane perpendicular to the magnetic field:

ion gyrofrequency, the angular frequency of the circular motion of an ion in the plane

perpendicular to the magnetic field:

electron plasma frequency, the frequency with which electrons oscillate (plasma

oscillation):

ion plasma frequency:

electron trapping rate:

ion trapping rate:

electron collision rate:

ion collision rate:

Lengths

Electron thermal de Broglie wavelength, approximate average de Broglie

wavelengthof electrons in a plasma:

classical distance of closest approach, the closest that two particles with the

elementary charge come to each other if they approach head-on and each have a

velocity typical of the temperature, ignoring quantum-mechanical effects:

electron gyroradius, the radius of the circular motion of an electron in the plane

perpendicular to the magnetic field:

ion gyroradius, the radius of the circular motion of an ion in the plane perpendicular

to the magnetic field:

plasmaskin depth, the depth in a plasma to which electromagnetic radiation can

penetrate:
https://en.wikipedia.org/wiki/Gaussian_unitshttps://en.wikipedia.org/wiki/Centimetre-gram-second_system_of_unitshttps://en.wikipedia.org/wiki/Temperaturehttps://en.wikipedia.org/wiki/Protonhttps://en.wikipedia.org/wiki/Protonhttps://en.wikipedia.org/wiki/Boltzmann's_constanthttps://en.wikipedia.org/wiki/Boltzmann's_constanthttps://en.wikipedia.org/wiki/Boltzmann's_constanthttps://en.wikipedia.org/wiki/Adiabatic_indexhttps://en.wikipedia.org/wiki/Coulomb_logarithmhttps://en.wikipedia.org/wiki/Plasma_oscillationhttps://en.wikipedia.org/wiki/Plasma_oscillationhttps://en.wikipedia.org/wiki/Thermal_de_Broglie_wavelengthhttps://en.wikipedia.org/wiki/De_Broglie_wavelengthhttps://en.wikipedia.org/wiki/De_Broglie_wavelengthhttps://en.wikipedia.org/wiki/De_Broglie_wavelengthhttps://en.wikipedia.org/wiki/Skin_depthhttps://en.wikipedia.org/wiki/Skin_depthhttps://en.wikipedia.org/wiki/Skin_depthhttps://en.wikipedia.org/wiki/Gaussian_unitshttps://en.wikipedia.org/wiki/Centimetre-gram-second_system_of_unitshttps://en.wikipedia.org/wiki/Temperaturehttps://en.wikipedia.org/wiki/Protonhttps://en.wikipedia.org/wiki/Boltzmann's_constanthttps://en.wikipedia.org/wiki/Boltzmann's_constanthttps://en.wikipedia.org/wiki/Adiabatic_indexhttps://en.wikipedia.org/wiki/Coulomb_logarithmhttps://en.wikipedia.org/wiki/Plasma_oscillationhttps://en.wikipedia.org/wiki/Plasma_oscillationhttps://en.wikipedia.org/wiki/Thermal_de_Broglie_wavelengthhttps://en.wikipedia.org/wiki/De_Broglie_wavelengthhttps://en.wikipedia.org/wiki/De_Broglie_wavelengthhttps://en.wikipedia.org/wiki/Skin_depth


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Debye length, the scale over which electric fields are screened out by a redistribution

of the electrons:

Ion inertial length, the scale at which ions decouple from electrons and the magnetic

field becomes frozen into the electron fluid rather than the bulk plasma:

Velocities

electron thermal velocity, typical velocity of an electron in a Maxwell-Boltzmann

distribution:

ion thermal velocity, typical velocity of an ion in a Maxwell-Boltzmann distribution:

ion sound velocity, the speed of the longitudinal waves resulting from the mass of the

ions and the pressure of the electrons:

Alfvn velocity, the speed of the wavesresulting from the mass of the ions and the

restoring force of the magnetic field:

Dimensionless

A 'sun in a test tube'. The Farnsworth-Hirsch Fusorduring operation in so called "star mode"

characterized by "rays" of glowing plasma which appear to emanate from the gaps in the inner

grid.

square root of electron/proton mass ratio

number of particles in a Debye sphere

Alfvn velocity/speed of light

electron plasma/gyrofrequency ratio

ion plasma/gyrofrequency ratio
https://en.wikipedia.org/wiki/Debye_lengthhttps://en.wikipedia.org/w/index.php?title=Ion_inertial_length&action=edit&redlink=1https://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Hannes_Alfv%C3%A9nhttps://en.wikipedia.org/wiki/Alfv%C3%A9n_wavehttps://en.wikipedia.org/wiki/Alfv%C3%A9n_wavehttps://en.wikipedia.org/wiki/Farnsworth-Hirsch_Fusorhttps://en.wikipedia.org/wiki/Farnsworth-Hirsch_Fusorhttps://en.wikipedia.org/wiki/Debye_lengthhttps://en.wikipedia.org/w/index.php?title=Ion_inertial_length&action=edit&redlink=1https://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Maxwell-Boltzmann_distributionhttps://en.wikipedia.org/wiki/Hannes_Alfv%C3%A9nhttps://en.wikipedia.org/wiki/Alfv%C3%A9n_wavehttps://en.wikipedia.org/wiki/Farnsworth-Hirsch_Fusor


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thermal/magnetic pressure ratio ("beta")

magnetic/ion rest energy ratio

See also List of plasma (physics) articles

References NRL Plasma Formulary (esp.p. 28 andp. 29), J.D. Huba,Naval Research Laboratory

(2007)

Footnotes1. ^ Peratt, Anthony,Physics of the Plasma Universe (1992);

2. ^ Parks, George K., Physics of Space Plasmas (2004, 2nd Ed.)
https://en.wikipedia.org/wiki/Beta_(plasma_physics)https://en.wikipedia.org/wiki/List_of_plasma_(physics)_articleshttp://www.ipp.mpg.de/~dpc/nrl/http://www.ipp.mpg.de/~dpc/nrl/28.htmlhttp://www.ipp.mpg.de/~dpc/nrl/29.htmlhttps://en.wikipedia.org/wiki/United_States_Naval_Research_Laboratoryhttps://en.wikipedia.org/wiki/Beta_(plasma_physics)https://en.wikipedia.org/wiki/List_of_plasma_(physics)_articleshttp://www.ipp.mpg.de/~dpc/nrl/http://www.ipp.mpg.de/~dpc/nrl/28.htmlhttp://www.ipp.mpg.de/~dpc/nrl/29.htmlhttps://en.wikipedia.org/wiki/United_States_Naval_Research_Laboratory

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Plasma Parameters