High-speed three-wave polarimeter-interferometer diagnostic for Madison symmetric torus
نویسندگان
چکیده
A high-speed three-wave polarimeter-interferometer diagnostic has been developed on the Madison symmetric torus reversed field pinch to provide simultaneous measurement of electron density and poloidal magnetic field profile evolution. With increased digitizer bandwidth, polarimetry noise due to aliasing and cross-talk is minimized, and time response improved. System performance is demonstrated by measurements of equilibrium profile evolution during fast events such as the sawtooth crash and pellet injection. © 2006 American Institute of Physics. #DOI: 10.1063/1.2222332$
منابع مشابه
Fizeau interferometer for measurement of plasma electron current
A high-resolution, vertically viewing far-infrared polarimeter-interferometer system is currently used on the Madison symmetric torus (MST) reversed-field pinch (RFP) to measure the plasma electron density and toroidal current density via Faraday rotation. In this article, we propose a scheme to measure the well-known Fizeau effect, whereby through modest modification of the existing apparatus,...
متن کاملAn upgraded interferometer-polarimeter system for broadband fluctuation measurements.
Measuring high-frequency fluctuations (above tearing mode frequencies) is important for diagnosing instabilities and transport phenomena. The Madison Symmetric Torus interferometer-polarimeter system has been upgraded to utilize improved planar-diode mixer technology. The new mixers reduce phase noise and allow more sensitive measurements of fluctuations at high frequency. Typical polarimeter r...
متن کاملA three-dimensional Gaussian-beam ray-tracing program for designing interferometerÕpolarimeter plasma diagnostics
We have developed a three-dimensional Gaussian-beam ray-tracing program to aid in the design of infrared, far-infrared, and millimeter wave interferometer and polarimeter diagnostic systems for magnetic confinement fusion relevant plasma physics experiments. An overview of the program is presented along with a description of the ray-tracing algorithm. A model is developed for the case of diffra...
متن کاملLocal measurements of tearing mode flows and the magnetohydrodynamic dynamo in the Madison Symmetric Torus reversed-field pinch
dynamo in the Madison Symmetric Torus reversed-field pinch D. A. Ennis, D. Craig, S. Gangadhara, J. K. Anderson, D. J. Den Hartog, F. Ebrahimi, G. Fiksel, and S. C. Prager The University of Wisconsin-Madison, Madison, Wisconsin 53706-1390, USA Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, Madison, Wisconsin 53706-1390, USA Wheaton College, Wheaton, Illinois 6018...
متن کاملLaser polarimetric measurement of equilibrium and fluctuating magnetic fields in a reversed field pinch „invited..
New developments in Faraday rotation polarimetry have provided the first measurements of current density profile and core magnetic fluctuations in the core of a high-temperature reversed field pinch. This has been achieved by a fast-polarimeter system with time response up to 1 ms and phase resolution ,1 mrad. Recent experiments on Madison Symmetric Torus have directly measured radial magnetic ...
متن کامل