Anisotropic cyclotron instability in the A.S. device

The experimental data obtained in the A.S. device are interpreted on the basis of the theory of cyclotron oscillations in an inhomogeneous magnetic field. According to this theory, the exchange of energy between oscillations and charged particles in the case of cyclotron resonance in an inhomogeneous magnetic field must be accompanied by the excitation of modulated beams similar to van Kampen waves. Under the conditions of the A.S. device, the modulated beams must give rise to electric fields that are not well correlated in space; this was observed in the experiment. Other features that characterize the unstable cyclotron oscillation can be understood on the basis of the theory of the anisotropic cyclotron in an inhomogeneous magnetic field. (author)