Maximum Entropy Analysis of the 2D Density Turbulence Measured by MIR in TPE-RX

Abstract

Two-dimensional (2D) turbulence measurement by using microwave imaging reflectometry (MIR) has been performed in the reversed field pinch (RFP) plasma in TPE-RX. In this work, the maximum entropy method (MEM) is used to estimate the 2D k-spectrum. The turbulences between the pulsed poloidal current drive (PPCD) and the high Θ plasmas are studied. The m = 1 modes are dominant in PPCD plasma, while in high Θ plasma the k spectrum expands to the high k range and the turbulence propagates in the electron drift direction. The preliminary result shows that PPCD plasma switches off the turbulence, and the high Θ plasma has strong turbulence.