Overview of Results from the National Spherical Torus Experiment (NSTX)

Gates, D; Ahn, J; Allain, J; Andre, R; Bastasz, R; Bell, M; Bell, R; Belova, E; Berkery, J; Betti, R; Bialek, J; Biewer, T; Bigelow, T; Bitter, M; Boedo, J; Bonoli, P; Bozzer, A; Brennan, D; Breslau, J; Brower, D; Bush, C; Canik, J; Caravelli, G; Carter, M; Caughman, J; Chang, C; Choe, W; Crocker, N; Darrow, D; Delgado-Aparicio, L; Diem, S; D'Ippolito, D; Domier, C; Dorland, W; Efthimion, P; Ejiri, A; Ershov, N; Evans, T; Feibush, E; Fenstermacher, M; Ferron, J; Finkenthal, M; Foley, J; Frazin, R; Fredrickson, E; Fu, G; Funaba, H; Gerhardt, S; Glasser, A; Gorelenkov, N; Grisham, L; Hahm, T; Harvey, R; Hassanein, A; Heidbrink, W; Hill, K; Hillesheim, J; Hillis, D; Hirooka, Y; Hosea, J; Hu, B; Humphreys, D; Idehara, T; Indireshkumar, K; Ishida, A; Jaeger, F; Jarboe, T; Jardin, S; Jaworski, M; Ji, H; Jung, H; Kaita, R; Kallman, J; Katsuro-Hopkins, O; Kawahata, K; Kawamori, E; Kaye, S; Kessel, C; Kim, J; Kimura, H; Kolemen, E; Krasheninnikov, S; Krstic, P; Ku, S; Kubota, S; Kugel, H; La Haye, R; Lao, L; LeBlanc, B; Lee, W; Lee, K; Leuer, J; Levinton, F; Liang, Y; Liu, D; Luhmann, N; Maingi, R; Majeski, R; Manickam, J; Mansfield, D; Maqueda, R; Mazzucato, E; McCune, D; McGeehan, B; McKee, G; Medley, S; Menard, J; Menon, M; Meyer, H; Mikkelsen, D; Miloshevsky, G; Mitarai, O; Mueller, D; Mueller, S; Munsat, T; Myra, J; Nagayama, Y; Nelson, B; Nguyen, X; Nishino, N; Nishiura, M; Nygren, R; Ono, M; Osborne, T; Pacella, D; Park, H; Park, J; Paul, S; Peebles, W; Penaflor, B; Peng, M; Phillips, C; Pigarov, A; Podesta, M; Preinhaelter, J; Ram, A; Raman, R; Rasmussen, D; Redd, A; Reimerdes, H; Rewoldt, G; Ross, P; Rowley, C; Ruskov, E; Russell, D; Ruzic, D; Ryan, P; Sabbagh, S; Schaffer, M; Schuster, E; Scott, S; Shaing, K; Sharpe, P; Shevchenko, V; Shinohara, K; Sizyuk, V; Skinner, C; Smirnov, A; Smith, D; Smith, S; Snyder, P; Soloman, W; Sontag, A; Soukhanovskii, V; Stoltzfus-Dueck, T; Stotler, D; Strait, T; Stratton, B; Stutman, D; Takahashi, R; Takase, Y; Tamura, N; Tang, X; Taylor, G; Taylor, C; Ticos, C; Tritz, K; Tsarouhas, D; Turrnbull, A; Tynan, G; Ulrickson, M; Umansky, M; Urban, J; Utergberg, E; Walker, M; Wampler, W; Wang, J; Wang, W; Weland, A

doi:10.1088/0029-5515/49/10/104016

Title: Overview of Results from the National Spherical Torus Experiment (NSTX)

Journal Article · Mon Jan 05 00:00:00 EST 2009 · Nuclear Fusion, vol. 49, no. 10, September 11, 2009, pp. 104016

DOI:https://doi.org/10.1088/0029-5515/49/10/104016· OSTI ID:966545

Gates, D; Ahn, J; Allain, J; Andre, R; Bastasz, R; Bell, M; Bell, R; Belova, E; Berkery, J; Betti, R; Bialek, J; Biewer, T; Bigelow, T; Bitter, M; Boedo, J; Bonoli, P; Bozzer, A; Brennan, D; Breslau, J; Brower, D more »

The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high {beta} operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies confirm the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance l{sub i} {approx} 0.4 with strong shaping ({kappa} {approx} 2.7, {delta} {approx} 0.8) with {beta}{sub N} approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction f{sub NI} {approx} 71%. Instabilities driven by super-Alfvenic ions are an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvenic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. RWM/RFA feedback combined with n = 3 error field control was used on NSTX to maintain plasma rotation with {beta} above the no-wall limit. The impact of n > 1 error fields on stability is a important result for ITER. Other highlights are: results of lithium coating experiments, momentum confinement studies, scrape-off layer width scaling, demonstration of divertor heat load mitigation in strongly shaped plasmas, and coupling of CHI plasmas to OH ramp-up. These results advance the ST towards next step fusion energy devices such as NHTX and ST-CTF.

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Research Organization:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Organization:: USDOE

DOE Contract Number:: W-7405-ENG-48

OSTI ID:: 966545

Report Number(s):: LLNL-JRNL-409680; TRN: US0904056

Journal Information:: Nuclear Fusion, vol. 49, no. 10, September 11, 2009, pp. 104016, Vol. 49, Issue 10

Country of Publication:: United States

Language:: English

References (40)

Divertor heat flux mitigation in the National Spherical Torus Experiment Soukhanovskii, V. A.; Maingi, R.; Gates, D. A. Physics of Plasmas, Vol. 16, Issue 2 https://doi.org/10.1063/1.3068170	journal	February 2009
Application of the low-frequency energy principle to wall modes Hu, Bo; Betti, R.; Manickam, J. Physics of Plasmas, Vol. 12, Issue 5 https://doi.org/10.1063/1.1873852	journal	May 2005
Neoclassical transport fluxes in the plateau regime in nonaxisymmetric toroidal plasmas Shaing, K. C.; Hirshman, S. P.; Callen, J. D. Physics of Fluids, Vol. 29, Issue 2 https://doi.org/10.1063/1.865439	journal	January 1986
Electron Bernstein wave simulations and comparison to preliminary NSTX emission data Preinhaelter, Josef; Urban, Jakub; Pavlo, Pavol Review of Scientific Instruments, Vol. 77, Issue 10 https://doi.org/10.1063/1.2336467	journal	October 2006
Canonical Hamiltonian guiding center variables White, Roscoe B. Physics of Fluids B: Plasma Physics, Vol. 2, Issue 4 https://doi.org/10.1063/1.859270	journal	April 1990
Hamiltonian guiding center drift orbit calculation for plasmas of arbitrary cross section White, R. B.; Chance, M. S. Physics of Fluids, Vol. 27, Issue 10 https://doi.org/10.1063/1.864527	journal	January 1984
Numerical simulation of bump‐on‐tail instability with source and sink Berk, H. L.; Breizman, B. N.; Pekker, M. Physics of Plasmas, Vol. 2, Issue 8 https://doi.org/10.1063/1.871198	journal	August 1995
Effect of plasma shaping on performance in the National Spherical Torus Experiment Gates, D. A.; Maingi, R.; Menard, J. Physics of Plasmas, Vol. 13, Issue 5 https://doi.org/10.1063/1.2198174	journal	May 2006
Internal kink mode dynamics in high-β NSTX plasmas Menard, J. E.; Bell, R. E.; Fredrickson, E. D. Nuclear Fusion, Vol. 45, Issue 7 https://doi.org/10.1088/0029-5515/45/7/001	journal	June 2005
Formation and Steady-State Sustainment of a Tokamak by Coaxial Helicity Injection Jarboe, Thomas R. Fusion Technology, Vol. 15, Issue 1 https://doi.org/10.13182/FST89-1	journal	January 1989
Divertor heat flux scaling with heating power and plasma current in H-mode discharges in the national spherical torus experiment Maingi, R.; Bush, C. E.; Kaita, R. Journal of Nuclear Materials, Vol. 363-365 https://doi.org/10.1016/j.jnucmat.2007.01.063	journal	June 2007
Investigation of HHFW and NBI Combined Heating in NSTX LeBlanc, B. P. RADIO FREQUENCY POWER IN PLASMAS: 16th Topical Conference on Radio Frequency Power in Plasmas, AIP Conference Proceedings https://doi.org/10.1063/1.2098201	conference	January 2005
Critical gradient formula for toroidal electron temperature gradient modes Jenko, F.; Dorland, W.; Hammett, G. W. Physics of Plasmas, Vol. 8, Issue 9 https://doi.org/10.1063/1.1391261	journal	September 2001
Investigation of resistive wall mode stabilization physics in high-beta plasmas using applied non-axisymmetric fields in NSTX Sontag, A. C.; Sabbagh, S. A.; Zhu, W. Nuclear Fusion, Vol. 47, Issue 8 https://doi.org/10.1088/0029-5515/47/8/035	journal	August 2007
Fast ion loss in a ‘sea-of-TAE’ Fredrickson, E. D.; Gorelenkov, N. N.; Bell, R. E. Nuclear Fusion, Vol. 46, Issue 10 https://doi.org/10.1088/0029-5515/46/10/S09	journal	September 2006
High harmonic fast wave heating efficiency enhancement and current drive at longer wavelength on the National Spherical Torus Experiment Hosea, J.; Bell, R. E.; LeBlanc, B. P. Physics of Plasmas, Vol. 15, Issue 5 https://doi.org/10.1063/1.2837051	journal	May 2008
New method for inductively forming an oblate field reversed configuration from a spheromak Gerhardt, S. P.; Belova, E. V.; Yamada, M. Nuclear Fusion, Vol. 48, Issue 3 https://doi.org/10.1088/0029-5515/48/3/032001	journal	January 2008
Localized measurement of turbulent fluctuations in tokamaks with coherent scattering of electromagnetic waves Mazzucato, E. Physics of Plasmas, Vol. 10, Issue 3 https://doi.org/10.1063/1.1541018	journal	March 2003
Features of spherical torus plasmas Peng, Y-K. M.; Strickler, D. J. Nuclear Fusion, Vol. 26, Issue 6 https://doi.org/10.1088/0029-5515/26/6/005	journal	June 1986
Active Stabilization of the Resistive-Wall Mode in High-Beta, Low-Rotation Plasmas Sabbagh, S. A.; Bell, R. E.; Menard, J. E. Physical Review Letters, Vol. 97, Issue 4 https://doi.org/10.1103/PhysRevLett.97.045004	journal	July 2006
H-mode research in NSTX Maingi, R.; Bell, M. G.; Bell, R. E. Nuclear Fusion, Vol. 43, Issue 9 https://doi.org/10.1088/0029-5515/43/9/322	journal	August 2003
A component test facility based on the spherical tokamak Peng, Y-K M.; Fogarty, P. J.; Burgess, T. W. Plasma Physics and Controlled Fusion, Vol. 47, Issue 12B https://doi.org/10.1088/0741-3335/47/12B/S20	journal	November 2005
Confinement and local transport in the National Spherical Torus Experiment (NSTX) Kaye, S. M.; Levinton, F. M.; Stutman, D. Nuclear Fusion, Vol. 47, Issue 7 https://doi.org/10.1088/0029-5515/47/7/001	journal	June 2007
The influence of rotation on the βN threshold for the 2∕1 neoclassical tearing mode in DIII-D Buttery, R. J.; La Haye, R. J.; Gohil, P. Physics of Plasmas, Vol. 15, Issue 5 https://doi.org/10.1063/1.2894215	journal	May 2008
Survey of theories of anomalous transport Conner, J. W.; Wilson, H. R. Plasma Physics and Controlled Fusion, Vol. 36, Issue 5 https://doi.org/10.1088/0741-3335/36/5/002	journal	May 1994
The effect of lithium surface coatings on plasma performance in the National Spherical Torus Experiment Kugel, H. W.; Bell, M. G.; Ahn, J. -W. Physics of Plasmas, Vol. 15, Issue 5 https://doi.org/10.1063/1.2906260	journal	May 2008
Short-Scale Turbulent Fluctuations Driven by the Electron-Temperature Gradient in the National Spherical Torus Experiment Mazzucato, E.; Smith, D. R.; Bell, R. E. Physical Review Letters, Vol. 101, Issue 7 https://doi.org/10.1103/PhysRevLett.101.075001	journal	August 2008
Exploration of spherical torus physics in the NSTX device Ono, M.; Kaye, S. M.; Peng, Y. -K. M. Nuclear Fusion, Vol. 40, Issue 3Y https://doi.org/10.1088/0029-5515/40/3Y/316	journal	March 2000
Drift waves and transport Horton, W. Reviews of Modern Physics, Vol. 71, Issue 3 https://doi.org/10.1103/RevModPhys.71.735	journal	April 1999
Comparison of initial value and eigenvalue codes for kinetic toroidal plasma instabilities Kotschenreuther, Mike; Rewoldt, G.; Tang, W. M. Computer Physics Communications, Vol. 88, Issue 2-3 https://doi.org/10.1016/0010-4655(95)00035-E	journal	August 1995
Non-inductive solenoid-free plasma start-up using coaxial helicity injection Raman, R.; Jarboe, T. R.; O'Neill, R. G. Nuclear Fusion, Vol. 45, Issue 4 https://doi.org/10.1088/0029-5515/45/4/L01	journal	April 2005
Observation of Plasma Toroidal-Momentum Dissipation by Neoclassical Toroidal Viscosity Zhu, W.; Sabbagh, S. A.; Bell, R. E. Physical Review Letters, Vol. 96, Issue 22 https://doi.org/10.1103/PhysRevLett.96.225002	journal	June 2006
Global δf particle simulation of neoclassical transport and ambipolar electric field in general geometry Wang, W. X.; Tang, W. M.; Hinton, F. L. Computer Physics Communications, Vol. 164, Issue 1-3 https://doi.org/10.1016/j.cpc.2004.06.027	journal	December 2004
Te(R,t) measurements using electron Bernstein wave thermal emission on NSTX Diem, S. J.; Taylor, G.; Efthimion, P. C. Review of Scientific Instruments, Vol. 77, Issue 10 https://doi.org/10.1063/1.2235112	journal	October 2006
Divertor heat flux reduction and detachment experiments in NSTX Soukhanovskii, V. A.; Maingi, R.; Bush, C. E. Journal of Nuclear Materials, Vol. 363-365 https://doi.org/10.1016/j.jnucmat.2007.01.075	journal	June 2007
The role of parallel heat transport in the relation between upstream scrape-off layer widths and target heat flux width in H-mode plasmas of the National Spherical Torus Experiment Ahn, J-W.; Boedo, J. A.; Maingi, R. Physics of Plasmas, Vol. 15, Issue 12 https://doi.org/10.1063/1.3043799	journal	December 2008
Spherical torus concept as power plants—the ARIES-ST study Najmabadi, F. Fusion Engineering and Design, Vol. 65, Issue 2 https://doi.org/10.1016/S0920-3796(02)00302-2	journal	February 2003
Momentum-Transport Studies in High $E \times B$ Shear Plasmas in the National Spherical Torus Experiment Solomon, W. M.; Kaye, S. M.; Bell, R. E. Physical Review Letters, Vol. 101, Issue 6 https://doi.org/10.1103/PhysRevLett.101.065004	journal	August 2008
Development of ITER-relevant plasma control solutions at DIII-D Humphreys, D. A.; Ferron, J. R.; Bakhtiari, M. Nuclear Fusion, Vol. 47, Issue 8 https://doi.org/10.1088/0029-5515/47/8/028	journal	July 2007
Overview of recent physics results from the National Spherical Torus Experiment (NSTX) Menard, J. E.; Bell, M. G.; Bell, R. E. Nuclear Fusion, Vol. 47, Issue 10 https://doi.org/10.1088/0029-5515/47/10/S13	journal	September 2007

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ELONGATION
FEEDBACK
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Title: Overview of Results from the National Spherical Torus Experiment (NSTX)

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