1ELECTRODYNAMICS OF HELICAL SLOWING STRUCTURE WITH HIGH-CURRENT ELECTRON BEAM

In most theoretical and experimental research, devoted to studying the interactions of beams with hybrid structures, the beam density is assumed small, therefore it does not change a structure of eigenwaves of electrodynamic system the beam interacts with. It is interesting to consider another limiting case, when the beam density is already so large, that natural oscillations of beam SDUWLkOHV ω E) are more than frequency of electromagnetic waves exited by beam, and when the presence of beam significantly changes the slowing structure electrodynamics. STATEMENT OF A PROBLEM In the present report we shall investigate theoretically and numerically the dispersion characteris-tics and find increments of instability of nonequilibrium systems with beams of large density that consist of annular electron beam moving along axes of helical slowing structure, which is immersed in strong external magnetic field directed parallel to the system axis. Let us consider a helical waveguide with radius 5 K, with helix period