High-resolution tomographic imaging of vacuum magnetic surfaces in the H-1 heliac
نویسنده
چکیده
A new, high-precision rotating wire grid apparatus for vacuum magnetic surface mapping of current-free toroidal plasma confinement geometries is described. This full-scaled version of the prototype apparatus developed on the SHEILA heliac has been tested and permanently installed on the H-1 heliac. Data of high quality are obtained with low electron energy ~,20 eV! to avoid drift errors, with submillimeter resolution and accuracy, within a 700 mm circular field of view. The apparatus avoids pixcell resolution limits and optical distortion, and is shown to be highly suited to precise comparison of computed and experimental magnetic surfaces, and after tomographic inversion, can produce useful images of the magnetic surfaces. © 1997 American Institute of Physics. @S0034-6748~97!72501-2#
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تاریخ انتشار 1996