Tokamak turbulence at the scrape-off layer in TCABR with an ergodic magnetic limiter

The influence of an ergodic magnetic limiter (EML) on plasma turbulence is investigated in the Tokamak Chauffage Alfvén Brésilien (TCABR), a tokamak with a peculiar natural superposition of the electrostatic and magnetic fluctuation power spectra. Experimental results show that the EML perturbation can reduce both the magnetic oscillation and the electrostatic plasma turbulence. Whenever this occurs, the turbulence-driven particle transport is also reduced. Moreover, a bispectral analysis shows that the nonlinear coupling between low- and high-frequency electrostatic fluctuations increases significantly with the EML application.