Wakefields in conducting waveguides with a lossy dielectric channel

Abstract

The resonant properties of the impedance of a two-layer circular metal-dielectric waveguide are investigated by taking into account the finite conductivity of the metallic pipe and the dissipation of the radiated energy in the dielectric layer. The dispersion relations for azimuthally symmetric monopole TM modes are analyzed. It is shown that, for an outer metallic layer with finite conductivity and a thin internal dielectric cover, the waveguide has only a single slowly propagating TM_{01} mode. The point charge longitudinal wake potentials are evaluated for thin and thick internal layers.