Cyclotron Harmonic Emission and Absorption Phenomena in a Non-Uniform Density Plasma

摘要

Cyclotron harmonic wave generation by non-relativistic fast electrons in a warm, collision-free, non-uniform electron density plasma slab is investigated. Ion motion is neglected and investigations are confined only to frequencies near the second cyclotron harmonic. The power absorption within, and power emission out of the plasma slab via mode conversion is calculated, including the effects of cyclotron damping caused by propagation of the waves in a direction not quite perpendicular to the static magnetic field. The transmission properties of the plasma slab for an incident electromagnetic field are determined. By making use of the 'fluctuation-dissipation' theorem the fast electron temperature is estimated from a comparison of the cyclotron harmonic emission and absorption spectrums. In order to make a comparison with experimental observations, electromagnetic wave propagation through the plasma slab is analysed. Similarities of the calculated power absorption spectrum with experimental results are verified from the plots of the electric fields. (Author)