DIAGNOSTICS OF MAGNETOPLASMAS BY LARGE ANGLE LASER SCATTERING,
Abstract
A review of experiments until 1967 on laser scattering from plasmas is given which indicates that any static magnetic field if present has not been utilized for diagnostics. The Appendix summarises the theory on scattering of electromagnetic waves from an infinite magnetoplasma with arbitrary velocity distributions for electrons and ions. It is shown that one can provide large angle scattering in the plane perpendicular to the magnetic field near certain electrostatic resonances, namely the upper hybrid (when the ratio of plasma to cyclotron frequency is greater than the sq. root of 3) and the cyclotron harmonics. The perpendicular wavenumbers associated with these magnetoplasma resonances can become large. Also the plasma resonance and upper hybrid resonance at low density are discussed. For densities 10 to the 12th power to 10 to the 13th power/cc, temperatures 2000 - 3000K, and using a 10.6 micron laser, the electron velocity distribution function is obtainable from the form of Landau damping acting on the plasma resonance, whereas collisional damping is usually stronger than cyclotron damping for the other resonances. Also the damping expression for the upper hybrid at high plasma densities suffers from complexities in analysis. All resonances are useful to yield electron density and temperature from the dispersion effects. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0653584
Entities
People
- I. P. Shkarofsky