Abstract
Summary form only given. Initial measurements of the electrostatic turbulence on the edge of the ATF torsatron are carried out in order to study their effect on the particle transport in this currentless magnetic configuration. Spatial profiles of the plasma electron density ne, temperature Te, and fluctuations in density (ne*) and in the plasma potential (φ) are measured around the last closed flux surface (LCFS) using a fast reciprocating Langmuir probe. Measurements made on electron cyclotron heated (ECH) plasmas indicate that at the LCFS Te approximately 20-40 eV and ne approximately 1012 cm-3 for a line-average electron density of (3-5) × 1012 cm-3 at 1 T operation. The fluctuations depart increasingly from the Boltzman relation eφ/Te = ne*/ne as the probe is moved into plasma where Te > 20 eV, with ne*/ne approximately 5%, eφ/Te approximately 2ne*/ne about 2 cm inside the LCFS. The radial variation of the DC radial electric field results in a velocity shear layer whose position is independent of the limiter location. The particle flux estimated from the global particle balance is comparable with the fluctuation-driven particle flux.
Original language | English |
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Pages | 79 |
Number of pages | 1 |
DOIs | |
State | Published - 1990 |
Event | 1990 IEEE International Conference on Plasma Science - Oakland, CA, USA Duration: May 21 1990 → May 23 1990 |
Conference
Conference | 1990 IEEE International Conference on Plasma Science |
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City | Oakland, CA, USA |
Period | 05/21/90 → 05/23/90 |