The amplification of fast extraordinary mode waves with frequencies very close to the electron cyclotron frequency is investigated for a plasma which consists of a weakly relativistic electron component with a loss-cone type distribution and a cold background electron component. The basic mechanism of the amplification is attributed to a relativistic cyclotron resonance between the wave and the energetic electrons. The method employed in the present analysis enables us to solve the dispersion relation in a self-consistent manner for arbitrary ratio of the densities of the energetic and background electrons. It is found that the maximum growth rates occur at certain values of ω2pe/Ω2e and the angular dependence of the growth rate is sensitive to the ratios ω2pe/Ω2e and ne/nb. Here ωpe and Ωe are the electron plasma frequency and the electron cyclotron frequency, respectively, and ne and nb denote the number densities of the energetic and background electrons, respectively.

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This work wai supported by the U.S. Department of Energy Contract No. DE-ACaZ-76-CHO. 3073. Reproduction, transla tion, publication, use and dijobsalj ir, whole or in part, by or for the United States government is pennittsd.

An equation describing the evolution of 2-D inhomogeneous magnetized plasma has been derived. In the cold ion case. it is merely a Euler equation or convective cell equation. There is a solitary flute vortex solution to it. Moreover. the structure of the solution is similar to that of the obiique vortex solution obtained by MAKIO et al. (1981) and MESS and HORTOS (1982. 1983i. but its properties differ from the latter in several aspects. There is no restriction on the speed of the vortex and it can propagate in an) direction in a plane with magnetic field B as it is normal. although the effect of a warm ion makes the vortices propagate anisotropically in the plane. The plasma appears to be adhered to vortices and mavins along with them. This means that the existence of flute vortices could be connected with conkection of particles and energy of plasma across magnetic surfaces.