IMPURITY TRANSPORT MEASUREMENTS OF BIASED H MODE IN HYDROGEN AND DEUTERIUM PLASMAS ON THE PHAEDRUS-T TOKAMAK

摘要

Soft X ray spectroscopy was used to study the transport of the dominating impu- rity, carbon, in the central region of the Phaedrus-T tokamak in ohmic and high confinement mode (H mode) plasmas. These H modes were induced by an electrode positioned in the edge of the plasma and biased positive with respect to the limiter. The primary source of carbon in the Phaedrus-T toka- mak plasma is the graphite limiter. A soft X ray polychromator utilizing multilayer mirrors (MLM) as dispersive elements simultaneously monitored the Lyman a emission of H-I-like carbon at 33.7A, and the blended singlet and triplet transitions of He-I-like carbon at 40.3 and 40.7A, respectively, and spatially resolved their distributions in the plasma with a temporal resolution of 1 ms.