Overview of physics results from MAST

B. Lloyd, R.J. Akers, F. Alladio, Y. Andrew, L.C. Appel, D. Applegate, K.B. Axon, N. Ben Ayed, A. Foster

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

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.
LanguageEnglish
PagesS658-S667
JournalNuclear Fusion
Volume47
Issue number10
DOIs
Publication statusPublished - Oct 2007

Fingerprint

physics
pellets
heating
aspect ratio
ions
scaling
electrons
thermal diffusivity
ablation
set theory
low speed
cascades
coils
shear
thresholds
high resolution
energy

Keywords

  • mega ampère spherical tokamak
  • tokamak
  • spherical tokamak
  • magnetohydrodynamic wave
  • pellet-fuelled discharge
  • pellet retention
  • plasma-material interaction
  • plasma disruption
  • plasma dynamics

Cite this

Lloyd, B., Akers, R. J., Alladio, F., Andrew, Y., Appel, L. C., Applegate, D., ... Foster, A. (2007). Overview of physics results from MAST. Nuclear Fusion, 47(10), S658-S667. https://doi.org/10.1088/0029-5515/47/10/S14
Lloyd, B. ; Akers, R.J. ; Alladio, F. ; Andrew, Y. ; Appel, L.C. ; Applegate, D. ; Axon, K.B. ; Ben Ayed, N. ; Foster, A. / Overview of physics results from MAST. In: Nuclear Fusion. 2007 ; Vol. 47, No. 10. pp. S658-S667.
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Lloyd, B, Akers, RJ, Alladio, F, Andrew, Y, Appel, LC, Applegate, D, Axon, KB, Ben Ayed, N & Foster, A 2007, 'Overview of physics results from MAST' Nuclear Fusion, vol. 47, no. 10, pp. S658-S667. https://doi.org/10.1088/0029-5515/47/10/S14

Overview of physics results from MAST. / Lloyd, B.; Akers, R.J.; Alladio, F.; Andrew, Y.; Appel, L.C.; Applegate, D.; Axon, K.B.; Ben Ayed, N.; Foster, A.

In: Nuclear Fusion, Vol. 47, No. 10, 10.2007, p. S658-S667.

Research output: Contribution to journalArticle

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Lloyd B, Akers RJ, Alladio F, Andrew Y, Appel LC, Applegate D et al. Overview of physics results from MAST. Nuclear Fusion. 2007 Oct;47(10):S658-S667. https://doi.org/10.1088/0029-5515/47/10/S14