Gyrotron R&D within the EUROfusion Work Package Heating and Current Drive (WPHCD) is
addressing the challenging requirements posed on gyrotrons by the European concept for a …

For the required upgrades of the Electron Cyclotron Resonance Heating system at the
stellarator Wendelstein 7-X, the development of a 1.5 MW 140 GHz Continuous Wave (CW) …

Lossy dielectric materials are used in gyrotron beam tunnels to suppress possible parasitic
oscillations by raising their starting currents. The dependence of the overall losses of the …

High-power gyrotrons may suffer from parasitic oscillations that are excited in the electron-
beam compression zone. Different damping structures are proposed in the literature that …

A model is presented for simulating the electron beam within the entire gyrotron geometry
using an electron optics code. The model incorporates the influence of the electromagnetic …

An in‐house full‐wave numerical code COCHLEA based on the Finite Difference in Time
Domain (FDTD) method has been developed and used to study the dispersion properties of …

Modern gyrotron beam tunnels are rather complicated structures designed to enhance the
suppression of the parasitic oscillations, which may be excited there. In some beam tunnel …

We develop a new self-consistent model for simulation of the electron–cyclotron maser
interaction in cylindrical structures, where expansion of the fields in transverse eigenmodes …

In this work we investigated the scattering parameters and mode conversion of axisymmetric
TE modes in smooth cylindrical waveguides with wedge-shaped azimuthal corrugations. In …

High-power gyrotrons often suffer from parasitic oscillations in the compression region
(beam tunnel) prior to the interaction cavity. A possible way to suppress the parasitic …