Energy load of a gyrotron collector with allowance for electrons reflected from its surface

We develop a physical model and an algorithm for calculation of the specific density of power scattered by a collector in high-power gyrotrons with allowance for multiple reflections of electrons from the collector surface. Specific features of the angular and energy distributions of reflected electrons in the case of their oblique incidence on the collector surface are taken into account. Electron trajectories and the corresponding power-density distributions for typical collector systems of the gyrotrons are found. Multiple reflections of electrons significantly increase the effective collector surface and reduce the thermal load.