JET disruption studies in support of ITER

Plasma disruptions affect plasma-facing and structural components of tokamaks due to electromechanical forces, thermal loads and generation of high energy runaway electrons (REs). Asymmetries in poloidal halo and toroidal plasma current can now be routinely measured in four positions 90° apart. Their assessment is used to validate the design of the ITER vessel support system and its in-vessel components. The challenge of disruption thermal loads comes from both the short duration over which a large energy has to be lost and the potential for asymmetries. The focus of this paper will be on localized heat loads. Resonant magnetic perturbations failed to reduce the generation of REs in JET. An explanation of the limitations applying to these attempts is offered together with a minimum guideline. The REs generated by a moderate, but fast, Ar injection in limiter plasmas show evidence of milder and more efficient losses due to the high Ar background density.

[1]  P. D. Morgan,et al.  Disruption mitigation by massive gas injection in JET , 2011 .

[2]  Jet Efda Contributors,et al.  Specification of asymmetric VDE loads of the ITER tokamak , 2011 .

[3]  J. Contributors,et al.  Heat load measurements on the JET first wall during disruptions , 2011 .

[4]  P. D. Morgan,et al.  Radiation loads onto plasma-facing components of JET during transient events – Experimental results and implications for ITER , 2011 .

[5]  W. Fundamenski,et al.  Modeling of runaway electron beams for JET and ITER , 2011 .

[6]  J. R. Martin-Solis,et al.  Magnetic energy flows during the current quench and termination of disruptions with runaway current plateau formation in JET and implications for ITER , 2011 .

[7]  J. R. Martin-Solis,et al.  EXS / 10-3 1 JET Disruption Studies in Support of ITER , 2010 .

[8]  T. Lunt,et al.  Disruption studies in ASDEX Upgrade in view of ITER , 2009 .

[9]  S. Brezinsek,et al.  JET experiments on massive gas injection , 2009 .

[10]  Jet Efda Contributors,et al.  Heat loads on plasma facing components during disruptions on JET , 2009 .

[11]  N. Lam,et al.  Progress in understanding halo current at JET , 2009 .

[12]  D. Reiter,et al.  Efficiency of massive gas injection for increase of plasma density in TEXTOR experiments on disruption mitigation , 2009 .

[13]  J. Contributors,et al.  First experiments on massive gas injection at JET - consequences for disruption mitigation in JET and ITER , 2009 .

[14]  T. Evans,et al.  Measurements of injected impurity assimilation during massive gas injection experiments in DIII-D , 2008 .

[15]  S. Bozhenkov,et al.  Suppression of runaway electrons by resonant magnetic perturbations in TEXTOR disruptions. , 2008, Physical review letters.

[16]  L. Zakharov.  The theory of the kink mode during the vertical plasma disruption events in tokamaks , 2008 .

[17]  M. Gryaznevich,et al.  Active control of type-I edge localized modes on JET. Invited Paper , 2007 .

[18]  T. Jernigan,et al.  Disruption mitigation on Alcator C-Mod using high-pressure gas injection: Experiments and modeling toward ITER , 2007 .

[19]  J. Manickam,et al.  Chapter 3: MHD stability, operational limits and disruptions , 2007 .

[20]  M. Sugihara,et al.  Disruption scenarios, their mitigation and operation window in ITER , 2007 .

[21]  W. Fundamenski,et al.  Transient heat loads in current fusion experiments, extrapolation to ITER and consequences for its operation , 2007 .

[22]  K. Spatschek,et al.  Influence of stochastic magnetic fields on relativistic electrons , 2006 .

[23]  J. B. Lister,et al.  DISRUPTION CHARACTERIZATION AND DATABASE ACTIVITIES FOR ITER , 2006 .

[24]  A. Loarte,et al.  Timescale and magnitude of plasma thermal energy loss before and during disruptions in JET , 2005 .

[25]  F. Andersson,et al.  Damping of relativistic electron beams by synchrotron radiation , 2001 .

[26]  L. Rossi,et al.  The error field correction coils on the JET machine , 2001 .

[27]  V. Riccardo,et al.  Forces between plasma, vessel and TF coils during AVDEs at JET , 2000 .

[28]  F. Andersson,et al.  Suppression of runaway electron avalanches by radial diffusion , 2000 .

[29]  Shinji Tokuda,et al.  Runaway electrons in magnetic turbulence and runaway current termination in tokamak discharges , 2000 .

[30]  V. Riccardo,et al.  Modelling magnetic forces during asymmetric vertical displacement events in JET , 2000 .

[31]  G. Sadler,et al.  Photoneutron production accompanying plasma disruptions in JET , 1988 .

[32]  G. Knoll.  Radiation detection and measurement , 1979 .