Microturbulence in HT-6M Tokamak

The small scale density fluctuations in the interior of HT-6M Ohmic plasma have been studied by CO₂ laser collective scattering system in deuterium discharges covering a range of n_eq_a (chord-average density times safety factor at the limiter) and energy confinement time. The relative density fluctuations level in the interior is inversely proportional to the toroidal magnetic field and average density, and the energy confinement time T_E decreases with the fluctuation level increasing in the region where T_E linearly increases with n_eq_a and satisfies the Goldston scaling Jaw. It is suggested that the microturbulence in the interior zone is responsible for anomalous transport in tokamaks.