TITLE

Recent developments of the JET far-infrared interferometer-polarimeter diagnostic

AUTHOR(S)
Boboc, A.; Gelfusa, M.; Murari, A.; Gaudio, P.; JET-EFDA Contributors
PUB. DATE
October 2010
SOURCE
Review of Scientific Instruments;Oct2010, Vol. 81 Issue 10, p10D538
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The far-infrared diagnostic provides essential internal measurements of the plasma density and magnetic field topology (q-profile via Faraday rotation angle) in real-time. The diagnostic capabilities have recently been extended in a number of key areas. Fast interferometer data, with 10 μs time resolution, and a new MATLAB code have allowed improved analysis of the evolution of density profiles during fast events such as vertical plasma displacements, edge localized mode, pellet fuelling, and disruptions. Using the polarimeter measurements in real-time, a new calibration procedure has been developed based on a propagation code using the Mueller matrix formalism. A further major upgrade of the system is presently underway: adding a second color laser to the vertical channels and implementing a new phase counter based on analog zero crossing and field-programmable gate array boards.
ACCESSION #
54857932

 

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