Recent results and future challenges in the systematic analytical description of plasma turbulence are described. First, the importance of statistical realizability is stressed, and the development and successes of the Realizable Markovian Closure are briefly reviewed. Next, submarginal turbulence (linearly stable but nonlinearly self-sustained fluctuations) is considered and the relevance of n...

Controlled nuclear fusion could provide our society with a clean, safe, and virtually inexhaustible source of electric power production. The tokamak has proven to be capable of producing large amounts of fusion reactions by confining magnetically the fusion fuel at sufficiently high density and temperature, thus in the plasma state. Because of turbulence, however, high temperature plasma reache...

We present the occultation observation of compact radio source B0019−000 through the plasma tail of comet SchwassmannWachmann 3-B. The observation was made with the Ooty Radio Telescope at 326.5 MHz on 2006 May 26, when the plasma tail of the comet was in front of this source. The scintillation was found to be increased significantly for the target source compared to that of a control source. T...

We describe and demonstrate a two-volume collective scattering system for localized measurements of plasma turbulence. The finite crossfield correlation length of plasma turbulence combined with spatial variations in the magnetic field direction are used to obtain spatially localized turbulence measurements at the Wendelstein 7-AS fusion experiment. By comparing with localized measurements obta...

Two-dimensional measurements of density fluctuations in the DIII-D tokamak, obtained with the Beam Emission Spectroscopy diagnostic, have allowed for construction of images and movies of plasma turbulence which are greatly aiding an understanding of tokamak turbulence phenomena. The measurements are obtained in the radial and poloidal plane at a spatial resolution of near 1 cm (about five ion g...