This paper presents the results of numerical simulations performed in COMSOL Multiphysics to study the spatial distribution of the electromagnetic field in a discharge inside a cylindrical resonator. The resonator is excited through a slot parallel to its axis. Two cases are considered—plasma in a uniform magnetic field and plasma in a magnetic mirror configuration. The results obtained are compared with analytical calculations of wave dispersion in a three-layer planar waveguide. The obtained results provide a qualitative explanation for the dependence of the impedance and spatial distribution of the electromagnetic field in an electron cyclotron discharge within a magnetic mirror configuration excited in a cylindrical resonator. These findings can be applied in the development of technological plasma sources and plasma accelerators where the plasma is sustained by an electromagnetic field in the electron cyclotron frequency range.
Dvinin et al. (Sun,) studied this question.