TFR experiments on superbanana particle diffusion, small-scale turbulence and transport

In a first experiment, the particles escaping the plasma along superbanana orbits are detected with a collector array. The flux increases sharply during ICRF heating in the minority regime. A theoretical model is presented of the trapping and acceleration processes in the region of proton-cyclotron resonance. The theory gives a fair description of the observed intensity and energy of the trapped flux. In a second experiment, electron density fluctuations are measured by microwave scattering. Azimuthal dependence of the fluctuations is found to be negligible in a regime where nusup(*) approximately 1. The turbulence and transport are found to be reduced when the electron density is increased above 1014cm-3. Anomalous heat transport is calculated, assuming trapped electron modes, and compared to the electron thermal balance. A rough agreement is found, if it is assumed that the unstable modes are strongly localized on magnetic rational surfaces. (author)