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Abstract: Fast 2-D cameras examine a variety of important aspects of the plasma edge and in-vessel components on the National Spherical Torus Experiment (NSTX). Four Phantom and two Miro visible-light cameras manufactured by Vision Research are used on NSTX for edge studies. Each camera can take several gigabytes (GBs) of data during each plasma pulse. Timely access to this amount of data can itself be a challenge, but analysing all these data using manual frame-by-frame examination is not practical. This paper describes image analysis, database techniques, and visualization methods used to organize the fast camera data and to facilitate physics insights from it. An example is presented of analysing and characterizing the size, movement and dynamics of coherent plasma structures (typically referred to as “blobs”) near the plasma edge. Software tools that generate statistics of blob speed, shape, amplitude, size, and orientation are described. The characteristics of emitted blobs affect plasma confinement and heat loads on plasma facing components, and are thus of particular interest to future machines like ITER. [Copyright &y& Elsevier]

Abstract: Animations from fast 2D camera data are facilitating the investigation of spatially distributed phenomena in high-temperature plasmas. The National Spherical Torus Experiment (NSTX) now has six fast camera systems, and more are expected to be added. Image capture rates vary between 1000 and 500,000 frames per second. Archiving and retrieving this data is a challenge for data repositories and networks. For example, if all camera data had been archived during the 2004 run, the total amount of data from NSTX (300MB per pulse) would have doubled, and this year, one new camera alone can acquire 2GB per pulse. The paper will describe the storage strategies, and compare some data compression techniques used for NSTX. Tools which animate camera data, synchronized with displays from other plasma diagnostics and simulations, allow scientists to gain insights and observe correlations that would be difficult with conventional tools. A labor-saving technique is described for archiving fast camera images from a vendor''s system into MDSplus and to AVI files. Examples of specific analysis and display techniques are presented. Future challenges are also discussed. [Copyright &y& Elsevier]

Abstract: The use of fast 2D cameras on NSTX continues to grow. There are 6 cameras with the capability of taking up to 1–2gigabytes (GBs) of data apiece during each plasma shot on the National Spherical Torus Experiment (NSTX). Efficient storage and retrieval of this data remains a challenge. Performance comparisons are presented for reading data stored in MDSplus, using both compressed data and segmented records, and direct access I/O with different read sizes. Encouragingly, fast 2D camera data provides considerable insight into plasma complexities, such as small-scale turbulence and particle transport. The last part of this paper is an example of more recent uses: dual cameras looking at the same region of the plasma from different angles, which can provide trajectories of incandescent particles in 3D. A laboratory simulation of the 3D trajectories is presented, as well as corresponding data from NSTX plasma where glowing dust particles can be followed. [ABSTRACT FROM AUTHOR]