AXIAL STRUCTURE OF A SHIELDED AXIALLY MAGNETIZED PLASMA-COLUMN SUSTAINED BY A DIPOLAR ELECTROMAGNETIC MODE

We consider an axially magnetized cold plasma column contained in a di electric tube, surrounded by vacuum and shielded by a metallic cylinde r. Closed-form analytical expressions for the wave dispersion relation , wave power, absorbed power and wave attenuation coefficient of the r ight-hand circularly polarized dipolar electromagnetic waves are given . In view of plasma production by such waves their phase diagrams are discussed. The external DC magnetic field is found to facilitate the c olumn sustainment, especially at low values of the product plasma radi us x wave frequency, and can remove occasionally occurring wave reflec tions from the column end. In the presence of a metallic shield one ca n observe fast wave propagation at higher powers. The axial structure of plasma columns sustained by the fundamental plasma mode HE11 has be en obtained under free-fall/diffusion gas-discharge regime. In the lim it of an infinite metallic cylinder radius the results for the wave ph ase and attenuation coefficients coincide with those derived numerical ly by Margot and Moisan (1991).