PPPL-3723 is available in <a href="PPPL-3723.pdf">pdf</a> format (388 KB).

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<b>Edge Turbulence Imaging on NSTX and Alcator C-Mod</b>
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<b>Authors:</b> S.J. Zweben, R.A. Maqueda, J.L. Terry, B. Bai, C.J. Boswell, C.E. Bush, D. D'Ippolito, E.D. Fredrickson, M. Greenwald, K. Hallatschek, S. Kaye, B. LaBombard, R. Maingi, J. Myra, W.M. Nevins, B.N. Rogers, D.P. Stotler, J. Wilgen, and X.Q. Xu
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<b>Date of PPPL Report:</b> July 2002
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<b>Presented at:</b> the 29th EPS Conference on Plasma Physics and Controlled Fusion, June 17-21, 2002, Montreux, Switzerland.</p>


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Edge turbulence images have been made using an ultra-high speed CCD camera on both NSTX [National Spherical Torus Experiment] and Alcator C-Mod. In both cases the D<font face="symbol"><sub>a</sub></font> or He<font face="symbol">I</font> (587.6 nm) line emission from localized deuterium or helium gas puffs was viewed along a local magnetic field line near the outer midplane. Fluctuations in this line emission reflect fluctuations in electron density (n<sub>e</sub>) and/or electron temperature (T<sub>e</sub>) through the atomic excitation rates, which can be modeled using the DEGAS-2 code. The 2-D structure of the measured turbulence can be compared with theoretical simulations based on 3-D fluid models.




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