Coil geometry and principal diagnostics (time-of-flight diagnostic not to scale).
Gaussian fit performed over an average of five shots looking at at . Here, and .
Current through the (a) limiter coil, (b) flux coil, and (c) total plasma current. Axial magnetic field (d) at the midplane on the outermost radius (solid) and innermost radius (dashed). Line integrated density (e) measured on a similar discharge. Standard plasma shot with 5.4 kV on the flux coil, 1.4 kV on the limiter coil, and 16 kV on the plasma guns.
Ion saturation current at various radii with standard charging parameters.
(a) Radial magnetic field profile at the midplane for a typical shot. Only seven probes are shown for clarity. (b) The interpolated null surface vs time.
Charge-exchange neutral particle velocity distribution uncorrected (dashed) and corrected (solid) for detection efficiency and charge exchange cross section energy dependence. Time averaged over for a standard plasma shot.
Neutral flux measurements looking in the cocurrent and countercurrent directions (solid). Cartoon indicating that peak of data lies below minimum detectable energy (dashed). Data shown are taken at for a typical shot.
Argon data with a Gaussian fit (solid) observed in the countercurrent direction showing a blueshift. The unshifted Gaussian (dashed) is shown for comparison.
Gaussian fit giving the mean PMT channel number observed in the cocurrent (△) and countercurrent (◇) directions. Error bars are calculated from the shot to shot variation in the discharges.
Average Doppler shift for observed spectral lines. Ion lines shown in (a) are carbon (solid), argon (dotted), and krypton (dashed). Neutral emission lines (b) are helium (solid) and hydrogen (dotted).
Effective temperatures for observed spectral lines: hydrogen (dashed-dot-dot-dot), helium (dashed-dot), carbon (solid), argon (dotted), and krypton (dashed).
Electron temperature as determined by the ratio of to . Error bars from statistical deviation of intensity between multiple shots.
Density profile obtained from pressure balance at while plasma is stable with the condition that the density goes to zero at the boundary.
Equilibrium fit to data for a typical shot to obtain equilibrium parameters at .
Equilibrium density profile using fitted parameters (solid) during a stable portion of the discharge along with the profile calculated from pressure balance (dashed) and ion-saturation current (×) scaled for reference.
Ion currents using density profiles obtained from pressure balance (dashed) and fitting to the equilibrium model (solid). Total plasma current shown (dotted) for comparison.
Electron rotation frequencies calculated from particle drifts (solid) and using the integrated density distributions obtained from the equilibrium model fit (dotted) and pressure balance (dashed).
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