Model for Current-Driven Edge-Localized Modes
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom)
Edge-localized modes (ELMs) are cyclic disturbances in the outer region of tokamak plasmas that are influential in determining present and future tokamak performance. In this Letter, we outline an approach to modeling ELMs in which we envisage toroidal peeling modes initiating a Taylor relaxation [Phys. Rev. Lett. 33, 1139 (1974)] of a tokamak outer region plasma. Relaxation produces a peeling destabilizing flattened edge current profile and a stabilizing plasma-vacuum current sheet; the balance between the two determines the radial extent of the relaxed region. The model can be used to predict the energy losses due to an ELM and reproduces experimentally observed variations with edge safety factor and plasma collisionality. There is an intrinsic 'deterministic scatter' in the model that also accords with observation.
- OSTI ID:
- 20776991
- Journal Information:
- Physical Review Letters, Vol. 96, Issue 3; Other Information: DOI: 10.1103/PhysRevLett.96.035006; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
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