Gyrotron as a source of probing radiation for collective Thomson scattering experiments

Collective Thomson scattering (CTS) of electromagnetic radiation from thermal electron density fluctuations in principle allows to measure the velocity distribution of plasma ions and their composition. The main concept of CTS diagnostic is based on the measurements of CTS spectra in some fixed scattering geometry. Because of extremely low level of scattered radiation a powerful source of probing radiation and a sensitive spectrum analyzing system are required for CTS. Powerful gyrotrons of mm wavelength region developed for electron cyclotron heating and current drive seem to have also good prospects to be used in collective scattering experiments