Current Status of the ECH Gyrotron System on the DIII-D Tokamak

The ECH gyrotron system at DIII-D consists of five 110-GHz Communications and Power Industries (CPI) diode tubes with non-depressed collectors currently available for plasma experiments in the 2023 campaign. In addition, one recently repaired CPI gyrotron with a depressed collector has begun testing. The RF power is injected into DIII-D via four dual equatorial electron cyclotron (EC) launchers, as well as two top EC launchers. DIII-D is currently preparing to design and install a fifth dual launcher and two transmission lines to accommodate new ITER-like, multifrequency gyrotrons in 2025.