Abstract
Circular limiter H modes with centrally peaked density profiles have been obtained on TFTR. Diagnostics used to study these unique plasmas include arrays of Dα and Cii detectors, bolometers, and Mirnov coils; x-ray imaging, charge exchange recombination spectroscopy, ECE, microwave scattering systems, and a multichannel infrared interferometer. These diagnostics have special features which allow time and space-resolved measurements during the H-mode transition and during ELMs. Microwave scattering during the H phase shows a feature in the scattered spectrum which is consistent with a poloidal rotation in the electron diamagnetic drift direction. Mirnov coil data digitized at 2 MHz show an increase in high-frequency magnetic fluctuations (60-200 kHz) during an ELM, while ECE data show 20-30 μs intense emission spikes in the outer 15-20 cm of the plasma edge.
Original language | English |
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Pages (from-to) | 3532-3535 |
Number of pages | 4 |
Journal | Review of Scientific Instruments |
Volume | 61 |
Issue number | 11 |
DOIs | |
State | Published - 1990 |