Design of the Collective Thomson Scattering Diagnostics for Large Helical Device using a Quasi-optical Frequency Tunable Gyrotron as a Radiation Source

摘要

Development of the collective Thomson scattering (CTS) diagnostic system for LHD is presented. High frequency, tunable (87-97 GHz), medium power (～100 kW) quasi-optical gyrotron will be used as a radiation source. We will show the detailed description of the system as well as initial calculations of the scattered microwave power from the LHD plasma. Using the quasi-optical gyrotron as a radiation source was inspired by the fact that this particular device has the ability of tuning of the operational frequency. Which is made it very attractive for using under the various scenarios for LHD plasmas.