Propagation characteristics and relation between electrostatic and magnetic fluctuations in DIT

摘要

An account is given of experiments on the DITE tokamak, using a fast reciprocating set of combined Langmuir and magnetic probes in the same discharge to compare the propagation characteristics of the turbulent electrostatic and magnetic perturbations with those expected from the measured local electric field and pressure gradient, and to investigate the effect of shear on cross-field transport. In addition, the relation between the electrostatic and magnetic aspects of the turbulence is investigated using direct cross-spectral measurements. The results are consistent with a picture in which magnetic fluctuations in the edge are due to the currents driven by the basically electrostatic turbulence, whose own propagation behaviour is dominated by the effects of the sheared E*B/B2velocity