Overview of physics results from MAST

Substantial advances have been made on the Mega Ampère Spherical Tokamak (MAST). The parameter range of the MAST confinement database has been extended and it now also includes pellet-fuelled discharges. Good pellet retention has been observed in H-mode discharges without triggering an ELM or an H/L transition during peripheral ablation of low speed pellets. Co-ordinated studies on MAST and DIII-D demonstrate a strong link between the aspect ratio and the beta scaling of H-mode energy confinement, consistent with that obtained when MAST data were merged with a subset of the ITPA database. Electron and ion ITBs are readily formed and their evolution has been investigated. Electron and ion thermal diffusivities have been reduced to values close to the ion neoclassical level. Error field correction coils have been used to determine the locked mode threshold scaling which is comparable to that in conventional aspect ratio tokamaks. The impact of plasma rotation on sawteeth has been investigated and the results have been well-modelled using the MISHKA-F code. Alfvén cascades have been observed in discharges with reversed magnetic shear. Measurements during off-axis NBCD and heating are consistent with classical fast ion modelling and indicate efficient heating and significant driven current. Central electron Bernstein wave heating has been observed via the O–X–B mode conversion process in special magnetically compressed plasmas. Plasmas with low pedestal collisionality have been established and further insight has been gained into the characteristics of filamentary structures at the plasma edge. Complex behaviour of the divertor power loading during plasma disruptions has been revealed by high resolution infra-red measurements.

P. M. Ryan | David R. Smith | Chase N. Taylor | K. C. Lee | J. Manickam | S. Jardin | C. Kessel | C. Rowley | L. Zakharov | R. Andre | D. McCune | K. Tritz | D. Stutman | R. Bell | A. Diallo | B. Leblanc | M. Podestà | D. Russell | T. Hahm | S. Ethier | L. Lao | T. Osborne | M. Walker | J. Ferron | E. Schuster | D. Humphreys | R. L. Haye | B. Penaflor | R. Betti | T. Evans | P. Bonoli | P. Snyder | J. Leuer | E. Belova | G. Fu | J. Wilgen | Y. Takase | K. Shaing | B. Hu | R. Harvey | G. Rewoldt | W. Dorland | E. Mazzucato | A. Boozer | N. Tamura | D. Gates | M. Finkenthal | C. Domier | N. Luhmann | J. Bialek | W. Wampler | R. Frazin | E. Kolemen | S. Gerhardt | D. Youchison | R. Nygren | S. Paul | R. Fonck | M. Menon | V. Soukhanovskii | H. Kugel | R. Kaita | R. Majeski | K. Indireshkumar | Jong-Kyu Park | A. Glasser | K. Wong | S. Zweben | Xianzhu Tang | E. Fredrickson | D. Mikkelsen | S. Sabbagh | M. Bell | F. Levinton | J. Menard | A. Sontag | H. Yuh | R. Buttery | M. Schaffer | H. Reimerdes | W. Solomon | A. Bortolon | W. Heidbrink | B. Nelson | D. Darrow | G. W. Taylor | T. Bigelow | J. Boedo | J. Hosea | S. Kubota | R. Maingi | S. Medley | D. Mueller | M. Ono | H. Park | C. Phillips | R. Raman | C. Skinner | P. Beiersdorfer | C. Chang | W. Davis | J. Foley | K. Hill | T. Jarboe | N. Nishino | D. Stotler | B. Stratton | G. Miloshevsky | A. Hassanein | S. Ding | D. Mansfield | A. Mclean | S. Krasheninnikov | V. Sizyuk | Woochan Lee | Roscoe White | H. Takahashi | W. Peebles | G. McKee | J. Preinhaelter | J. Urban | R. Maqueda | A. Pigarov | D. D'Ippolito | J. Myra | G. Yu | M. Umansky | Joon-Wook Ahn | J. Allain | R. Bastasz | D. Battaglia | J. Berkery | M. Bitter | D. Brennan | J. Breslau | J. Canik | G. Caravelli | N. Crocker | L. Delgado-Aparicio | N. Gorelenkov | T. Gray | Y. Guo | W. Guttenfelder | Y. Hirooka | E. Hooper | F. Jaeger | M. Jaworski | J. Kallman | O. Katsuro-Hopkins | S. Kaye | J. Kim | Y. Liang | D. Liu | B. McGeehan | H. Meyer | T. Munsat | Y. Ren | P. Ross | E. Ruskov | D. Ruzic | F. Scotti | V. Shevchenko | K. Shinohara | A. Smirnov | T. Stoltzfus-Dueck | C. Taylor | Dimitris Tsarouhas | W. Wang | J. Whaley | R. Wilson | J. Wright | Z. Xia | D. Zemlyanov | G. Zimmer | H. Park | Jongkyu Park | R. White | C. Chang | W. Lee | C. Taylor | C. Chang | G. Taylor | P. Ryan | B. LeBlanc | K. Lee

[1]  Y. Kamada,et al.  Pedestal stability comparison and ITER pedestal prediction , 2009 .

[2]  E. Mazzucato,et al.  A collective scattering system for measuring electron gyroscale fluctuations on the National Spherical Torus Experiment. , 2008, The Review of scientific instruments.

[3]  P. J. Knight,et al.  Conceptual design of a component test facility based on the spherical tokamak , 2008 .

[4]  H. Wilson,et al.  Experiments and simulation of edge turbulence and filaments in MAST , 2008 .

[5]  R. Bell,et al.  The NSTX fast-ion D-alpha diagnostic. , 2008, The Review of scientific instruments.

[6]  N. Hawkes,et al.  Ab initio modeling of the motional Stark effect on MAST. , 2008, The Review of scientific instruments.

[7]  T O'Gorman,et al.  Design of a new Nd:YAG Thomson scattering system for MAST. , 2008, The Review of scientific instruments.

[8]  L. Appel,et al.  Compressional Alfvén Eigenmodes on MAST , 2008 .

[9]  R. Bell,et al.  Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus Experiment. , 2008 .

[10]  P. M. Ryan,et al.  Short-scale turbulent fluctuations driven by the electron-temperature gradient in the national spherical torus experiment. , 2008, Physical review letters.

[11]  P. Catto,et al.  Arbitrary poloidal gyroradius effects in tokamak pedestals and transport barriers , 2008 .

[12]  R. Scannell,et al.  The structure, evolution and role of the radial edge electric field in H-mode and L-mode on MAST , 2008 .

[13]  S. Pinches,et al.  Recent experiments on Alfvén eigenmodes in MAST , 2008 .

[14]  G. Maddison,et al.  Particle confinement of pellet-fuelled tokamak plasma , 2008 .

[15]  Dimensionless parameter dependence of H-mode pedestal width using hydrogen and deuterium plasmas in JT-60U , 2008 .

[16]  T. C. Luce,et al.  Application of dimensionless parameter scaling techniques to the design and interpretation of magnetic fusion experiments , 2008 .

[17]  S. Saarelma,et al.  Confinement and Fuelling in Mast , 2008 .

[18]  Experimental observation of inter-ELM filaments in MAST , 2008 .

[19]  A. Kirk,et al.  ELM power loadings and control on MAST using resonant magnetic perturbations , 2008 .

[20]  S. Pinches,et al.  1 EX / P 6-26 Current profile control studies on MAST , 2008 .

[21]  J. Kinsey,et al.  TH / P 842 Testing the Trapped Gyro-Landau Fluid Transport Model with Data from Tokamaks and Spherical Tori , 2008 .

[22]  S. E. Lysenko,et al.  Canonical Profiles Transport Model for H-mode Shots in Tokamaks , 2008 .

[23]  Jet Efda Contributors,et al.  The physics of sawtooth stabilization , 2007 .

[24]  J. Weiland,et al.  Toroidal and poloidal momentum transport studies in tokamaks , 2007 .

[25]  T. Hender,et al.  Locked mode thresholds on the MAST spherical tokamak , 2007 .

[26]  G. A. Navratil,et al.  Stability and control of resistive wall modes in high beta, low rotation DIII-D plasmas , 2007, Nuclear Fusion.

[27]  N Hawkes,et al.  Active control of type-I edge-localized modes with n=1 perturbation fields in the JET tokamak. , 2007, Physical review letters.

[28]  A. Peeters,et al.  Toroidal momentum pinch velocity due to the coriolis drift effect on small scale instabilities in a toroidal plasma. , 2007, Physical review letters.

[29]  K. Tritz,et al.  Confinement and local transport in the National Spherical Torus Experiment (NSTX) , 2007 .

[30]  H. Laqua,et al.  Electron Bernstein wave heating and diagnostic , 2007 .

[31]  S. Voskoboynikov,et al.  Active control of the H-mode transition on MAST , 2007 .

[32]  C. Giroud,et al.  Scaling of density peaking in H-mode plasmas based on a combined database of AUG and JET observations , 2007 .

[33]  S. Saarelma,et al.  The effect of toroidal plasma rotation on sawteeth in MAST , 2006 .

[34]  T. Eich,et al.  Filament structures at the plasma edge on MAST , 2006 .

[35]  Detection of short-scale turbulence in the next generation of tokamak burning plasma experiments , 2006 .

[36]  P. Valanju,et al.  On heat loading, novel divertors, and fusion reactors , 2006 .

[37]  S. Prunty,et al.  Enhanced edge Thomson scattering on MAST , 2006 .

[38]  N. Hawkes,et al.  Motional Stark effect diagnostic pilot experiment for MAST , 2006 .

[39]  S. Voskoboynikov,et al.  Modelling of radial electric field profile for different divertor configurations , 2006 .

[40]  Keith H. Burrell,et al.  Edge stability and transport control with resonant magnetic perturbations in collisionless tokamak plasmas , 2006 .

[41]  R. Scannell,et al.  Evolution of filament structures during edge-localized modes in the MAST Tokamak. , 2006, Physical review letters.

[42]  G. Huysmans,et al.  Modeling the effect of toroidal plasma rotation on drift-magnetohydrodynamic modes in tokamaks , 2006 .

[43]  S. Coda,et al.  Exploring a small sawtooth regime in Joint European Torus plasmas with counterinjected neutral beams , 2006 .

[44]  R. Bell,et al.  Energy confinement scaling in the low aspect ratio National Spherical Torus Experiment (NSTX) , 2005 .

[45]  Y. R. Martin,et al.  The role of aspect ratio and beta in H-mode confinement scalings , 2005 .

[46]  K. F. Mast,et al.  Overview of ASDEX Upgrade results—development of integrated operating scenarios for ITER , 2005 .

[47]  G. Hogeweij,et al.  Profile-turbulence interactions, magnetohydrodynamic relaxations, and transport in tokamaks , 2005 .

[48]  E. D. Fredrickson,et al.  H-mode pedestal, ELM and power threshold studies in NSTX , 2005 .

[49]  C. Brickley,et al.  Energy and particle confinement in MAST , 2005 .

[50]  Monte Carlo orbit/full wave simulation of ion cyclotron resonance frequency wave damping on resonant ions in tokamaks , 2005 .

[51]  J. Juul Rasmussen,et al.  Turbulence and intermittent transport at the boundary of magnetized plasmas , 2005 .

[52]  K. McClements,et al.  Improved H-mode access in connected DND in MAST , 2005 .

[53]  S. J. Wukitch,et al.  Transport-driven scrape-off layer flows and the x-point dependence of the L-H power threshold in Alcator C-Mod , 2005 .

[54]  J. Manickam,et al.  Application of the low-frequency energy principle to wall modesa) , 2005 .

[55]  P. Carolan,et al.  Anisotropic fast neutral particle spectra in the MAST spherical tokamak , 2005 .

[56]  Generation of toroidal rotation by gas puff. Simulations of MAST experiments with B2SOLPS5.0 , 2005 .

[57]  S. Saarelma,et al.  H-mode physics of near double null plasmas in MAST and its applications to other tokamaks , 2005 .

[58]  C. Kessel,et al.  Advanced ST plasma scenario simulations for NSTX , 2004 .

[59]  J. Scoville,et al.  Measurement of the resistive-wall-mode stability in a rotating plasma using active MHD spectroscopy. , 2004, Physical review letters.

[60]  W. Fundamenski,et al.  A comparison of mid-plane scrape-off-layer measurements with model predictions in MAST and the calculation of cross-field transport coefficients , 2004 .

[61]  R. A. Cairns,et al.  Integrated plasma physics modelling for the Culham steady state spherical tokamak fusion power plant , 2004 .

[62]  S. Sharapov,et al.  Beta-dependence of energetic particle-driven instabilities in spherical tokamaks , 2004 .

[63]  A. Kirk,et al.  Spatial and temporal structure of edge-localized modes. , 2004, Physical review letters.

[64]  M E Fenstermacher,et al.  Suppression of large edge-localized modes in high-confinement DIII-D plasmas with a stochastic magnetic boundary. , 2004, Physical review letters.

[65]  P. Helander,et al.  The influence of gas fuelling location on H-mode access in the MAST spherical tokamak , 2004 .

[66]  H R Wilson,et al.  Theory for explosive ideal magnetohydrodynamic instabilities in plasmas. , 2004, Physical review letters.

[67]  Choong-Seock Chang,et al.  Numerical study of neoclassical plasma pedestal in a tokamak geometry , 2004 .

[68]  M. Valovič,et al.  H-mode pedestal characteristics on MAST , 2004 .

[69]  J. Contributors,et al.  JET divertor geometry and plasma shape effects on the L H transition threshold , 2004 .

[70]  G. F. Counsell,et al.  ELM characteristics in MAST , 2004 .

[71]  C. D. Challis,et al.  Transport and confinement in the Mega Ampère Spherical Tokamak (MAST) plasma , 2003 .

[72]  X. Garbet,et al.  Turbulent particle transport in magnetized plasmas. , 2003, Physical review letters.

[73]  H. Weisen,et al.  Observation and empirical modelling of the anomalous particle pinch in TCV , 2003 .

[74]  E. D. Fredrickson,et al.  β-Limiting MHD instabilities in improved-performance NSTX spherical torus plasmas , 2003 .

[75]  O. Sauter,et al.  The internal kink mode in an anisotropic flowing plasma with application to modeling neutral beam injected sawtoothing discharges , 2003 .

[76]  R. C. Wolf,et al.  Internal transport barriers in tokamak plasmas , 2003 .

[77]  Y. Baranov,et al.  Generation of noninductive current by electron-Bernstein waves on the COMPASS-D Tokamak. , 2002, Physical review letters.

[78]  R. Felton,et al.  High density operation at JET by pellet refuelling , 2002 .

[79]  W. Heidbrink,et al.  Beam-driven energetic particle modes in advanced tokamak plasmas , 2002 .

[80]  C. D. Challis,et al.  Alfvén wave cascades in a tokamak , 2002 .

[81]  H. Wilson,et al.  Numerical studies of edge localized instabilities in tokamaks , 2002 .

[82]  M. Nightingale,et al.  The MAST neutral beam injection system , 2001 .

[83]  Eduardo F. D'Azevedo,et al.  All-orders spectral calculation of radio-frequency heating in two-dimensional toroidal plasmas , 2001 .

[84]  V. Shevchenko.  ECE measurements via B-X-O mode conversion: A proposal to diagnose the q profile in spherical tokamaks , 2000 .

[85]  A. Bondeson,et al.  Stabilization of the internal kink mode in a tokamak by toroidal plasma rotation , 2000 .

[86]  P. Terry,et al.  Suppression of turbulence and transport by sheared flow , 2000 .

[87]  D. J. Campbell,et al.  Chapter 1: Overview and summary , 1999 .

[88]  M. Rosenbluth,et al.  Chapter 5: Physics of energetic ions , 1999 .

[89]  R. L. Haye,et al.  Error field mode studies on JET, COMPASS-D and DIII-D, and implications for ITER , 1999 .

[90]  T. Hender,et al.  Error field penetration and plasma rotation in H mode and control of ELM-free regimes in COMPASS-D , 1999 .

[91]  R. Groebner,et al.  Turbulence studies in tokamak boundary plasmas with realistic divertor geometry , 1998 .

[92]  G. Fishpool.  Loss of confinement due to reduction of the edge pedestal in JET , 1998 .

[93]  Herbert L Berk,et al.  The HAGIS self-consistent nonlinear wave-particle interaction model , 1998 .

[94]  T. Hender,et al.  Effects of resonant magnetic perturbations on divertor target power loads in COMPASS-D , 1996 .

[95]  Francois Waelbroeck,et al.  Gyroscopic stabilization of the internal kink mode , 1996 .

[96]  H. Zohm.  Edge localized modes (ELMs) , 1996 .

[97]  Mike Kotschenreuther,et al.  Comparison of initial value and eigenvalue codes for kinetic toroidal plasma instabilities , 1995 .

[98]  G. M. Voss,et al.  MAST: A Mega Amp Spherical Tokamak , 1995 .

[99]  Riccardo Betti,et al.  Stability of Alfven gap modes in burning plasmas , 1992 .

[100]  Chio-Zong Cheng,et al.  Kinetic extensions of magnetohydrodynamics for axisymmetric toroidal plasmas , 1992 .

[101]  Bonaventure Intercontinental,et al.  ON DECISION AND CONTROL , 1985 .

[102]  M. S. Chance,et al.  Hamiltonian guiding center drift orbit calculation for plasmas of arbitrary cross section , 1984 .

[103]  S. J. Zweben,et al.  Optical imaging of edge turbulence in the caltech tokamak , 1983 .

[104]  D.H.J. Goodall,et al.  High speed cine film studies of plasma behaviour and plasma surface interactions in tokamaks , 1982 .

[105]  R. J. Hawryluk,et al.  An Empirical Approach to Tokamak Transport , 1981 .

[106]  C. A. Foster,et al.  A Revised Neutral Gas Shielding Model for Pellet-Plasma Interactions , 1978, IEEE Transactions on Plasma Science.

[107]  R. J. Turnbull,et al.  Effect of transonic flow in the ablation cloud on the lifetime of a solid hydrogen pellet in a plasma , 1978 .