Study of Low-Frequency Microturbulence in the Microtor Tokamak by Far-Infrared Laser Scattering

Abstract

The first far-infrared laser scattering measurements from a tokamak plasma are reported. Spatially and temporally resolved power spectra of density fluctuations in the Microtor plasma have been studied with an absolutely calibrated far-infrared scattering system which allowed measurement of the wide range of wave numbers from $k=3 \mathrm{to} 50$ ${\mathrm{cm}}^{\ensuremath{-}1}$. The wave-number dependence of the scattered power of $0.6\ensuremath{\lesssim}{k}_{\ensuremath{\perp}}{\ensuremath{\rho}}_{i}\ensuremath{\lesssim}2$ was found to satisfy a ${k}^{\ensuremath{-}3.5}$ form.