Electron gyroscale fluctuation measurements in National Spherical Torus Experiment H-mode plasmas

Abstract

A collective scattering system has measured electron gyroscale fluctuations in National Spherical Torus Experiment [M. Ono, Nucl. Fusion 40, 557 (2000)] H-mode plasmas to investigate electron temperature gradient (ETG) turbulence. Observations and results pertaining to fluctuation measurements in ETG-stable regimes, the toroidal field scaling of fluctuation amplitudes, the relation between fluctuation amplitudes and transport quantities, and fluctuation magnitudes and k -spectra are presented. Collectively, the measurements provide insight and guidance for understanding ETG turbulence and anomalous electron thermal transport. © 2009 American Institute of Physics.