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MSE Progress S. D. Scott and Howard Yuh October 28, 2002. Mselog Data acquisition issues DNB performance MSE dataset Shot-to-shot variation Issue at moderate and high density – density scan Sawtooth. I hope to show a slide like the following at the DoE review:. Measured q from edge
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MSE ProgressS. D. Scott and Howard YuhOctober 28, 2002 • Mselog • Data acquisition issues • DNB performance • MSE dataset • Shot-to-shot variation • Issue at moderate and high density – density scan • Sawtooth
I hope to show a slide like the following at the DoE review: Measured q from edge channel or measured Pitch-angle 3 6 Edge Qpsi from Efit
We have acquired a large MSE dataset: qpsi = 2.8-7.6 (about 600 points)
Range of Q for Nel<0.8 is more limited butstill covers a range of 2+ in edge q
Possible problems with q-measurementat high density? – individual shots Nel4 Series 4 0.46-0.58 Series 11 0.65-0.85 Series 18 1.01-1.10 Run day = 1021017 Series 4: 29, 30, 32 Series 11: 20, 21, 28 Series 18: 22, 26, 27
Possible problems with q-measurementat high density? Nel4 Series 4 0.46-0.58 Series 11 0.65-0.85 Series 18 1.01-1.10 Run day = 1021017 Series 4: 29, 30, 32 Series 11: 20, 21, 28 Series 18: 22, 26, 27
Shot-to-Shot Scatter in Pitch-Angle increases with density (linear scale)
Comparison of shot-to-shot scatterin low-density plasmas: recent data versus August 9
Apparent Pitch-angle changes at Onset of Sawteeth • Data from October 18, 2002 • Before and after onset of sawteeth • 50 ms integration period • Error bars shown are +1 sigma and • -1 sigma, where sigma is equal to the • shot-to-shot variation.