PPPL-3533 is available in <a href="PPPL-3533.pdf">pdf</a> (3.4 MB) only.

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<b>Initial Physics Results From the National Spherical Torus Experiment</b>
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Authors: S.M. Kaye, M.G. Bell, R.E. Bell, J. Bialek, T. Bigelow, M. Bitter, P. Bonoli, D. Darrow, P. Efthimion, J. Ferron, E. Fredrickson, D. Gates, L. Grisham, J. Hosea, D. Johnson, R. Kaita, S. Kubota, H. Kugel, B. LeBlanc, R. Maingi, J. Manickam, T.K. Mau, R.J. Maqueda, E. Mazzucato, J. Menard, D. Mueller, B. Nelson, N. Nishino, M. Ono, F. Paoletti, S. Paul, Y-K.M. Peng, C.K. Phillips, R. Raman, P.Ryan, S.A. Sabbagh, M. Schaffer, C.H. Skinner, D. Stutman, D. Swain, E. Synakowski, Y. Takase, J. Wilgen, J.R. Wilson, W. Zhu, S. Zweben, A. Bers, M. Carter, B. Deng, C. Domier, E. Doyle, M. Finkenthal, K. Hill, T. Jarboe, S. Jardin, H. Ji, L. Lao, K.C. Lee, N. Luhmann, R. Majeski, S. Medley, H. Park, T. Peebles, R.I. Pinsker, G. Porter, A. Ram, M. Rensink, T. Rognlien,  D. Stotler, B. Stratton, G. Taylor, W. Wampler, G.A. Wurden, X.Q. Xu, L. Zeng, and the NSTX Team
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<b>Date of PPPL Report:</b> January 2001 (corrected copy posted January 30, 2001)
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<b>Published in:</b> Phys. Plasmas <b>8</b> (May 2001) 1977-1987. 
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The mission of the National Spherical Torus Experiment (NSTX) is to extend the understanding of toroidal physics to low aspect ratio (R/a approximately equal to 1.25) in low collisionality regimes. NSTX is designed to operate with up to 6 MW of High Harmonic Fast Wave (HHFW) heating and current drive, 5 MW of Neutral Beam Injection (NBI) and Co-Axial Helicity Injection (CHI) for noninductive start-up. Initial experiments focused on establishing conditions that will allow NSTX to achieve its aims of simultaneous high-<font face ="symbol">b</font><sub>t</sub> and high-bootstrap current fraction, and to develop methods for noninductive operation, which will be necessary for Spherical Torus power plants. Ohmic discharges with plasma currents up to 1 MA and with a range of shapes and configurations were produced. Density limits in deuterium and helium reached 80% and 120% of the Greenwald limit, respectively. Significant electron heating was observed with up to 2.3 MW of HHFW. Up to 270 kA of toroidal current for up to 200 msec was produced noninductively using CHI. Initial NBI experiments were carried out with up to two beam sources (3.2 MW). Plasmas with stored energies of up to 140 kJ and <font face ="symbol">b</font><sub>t</sub> = 21% were produced.

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