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Extension of Dougherty's model Fokker--Planck equation for a plasma

Journal Article · · J. Plasma Phys., v. 11, pp. 11-35
OSTI ID:4334272

A generalization of the Appleton- Hartree equation was made to include the effects of energy-dependent electron-- neutron collisions, Coulomb encounters and spatial dispersion. The frequency of electromagnetic waves propagating in a magnetoplasma is sufficiently high that the ion motion may be neglected compared with the electron motion. The present analysis extended Dougherty (Dougherty, J. P., 1963, J. Fluid Mech. 16, 126; Dougherty, J. P., 1964, Phys, Fluids, 7, 1788) to include the simultaneous effect on wave propagation of Coulomb forces, spatial dispersion and energy-dependent electron-neutral collisions, where one or more of these effects could have a significant influence on circularly polarized waves propagating at frequencies near electron cyclotron resonance. The electrical conductivity tensor was expressible in terms of appropriate velocity moments of the electron distribution function. The electron velocity distribution function was determined by expanding the inverse of the differential operator of the linearized kinetic equation in a small parameter epsilon /sub 2/, where in one case epsilon /sub 2/ w as the ratio of Coulomb collision frequency to signal frequency, and in the second case epsilon /sub 2/ was the ratio of electron- neutral collision frequency to signal frequency. For wave propagation along the magnetic field, the dispersion relation for longitudinal waves were solved numerically, and graphs were presented to show the effects of collisionless damping, velocity dependent electron-neutral collisions and Coulomb collisions. (auth)

Research Organization:
Air Force Cambridge Research Labs., L. G. Hanscom Field, MA
NSA Number:
NSA-29-025745
OSTI ID:
4334272
Journal Information:
J. Plasma Phys., v. 11, pp. 11-35, Journal Name: J. Plasma Phys., v. 11, pp. 11-35; ISSN JPLPB
Country of Publication:
United Kingdom
Language:
English