Ion Cyclotron Range of Frequencies Mode Conversion Electron Heating in Deuterium-Hydrogen Plasmas in the Alcator C-Mod Tokamak
نویسندگان
چکیده
Localized direct electron heating by mode-converted ion cyclotron range of frequencies (ICRF) waves in D(H) tokamak plasmas has been clearly observed for the first time in Alcator C-Mod. Both onand off-axis (high field side) mode conversion electron heating (MCEH) have been observed. The MCEH profile was obtained from a break in slope analysis of electron temperature signals in the presence of rf (radio frequency) shut-off. The temperature was measured by a 32-channel high spatial resolution (≤ 7 mm) 2 harmonic heterodyne electron cyclotron emission (ECE) system. The experimental profiles were compared with the predictions from a toroidal full-wave ICRF code TORIC. Using the hydrogen concentration measured by a high-resolution optical spectrometer, TORIC predictions were shown qualitatively in agreement with the experimental results for both onand off-axis MC cases. From the simulations, the electron heating from mode converted ion cyclotron wave (ICW) and ion Bernstein wave (IBW) is examined.
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