Observation Of Edge Instability Limiting The Pedestal Growth in Tokamak Plasmas
Authors: Ahmed Diallo, et. al.
Abstract:
With fusion device performance hinging on the edge pedestal pressure, it is imperative to experimentally
understand the physical mechanism dictating the pedestal characteristics and to validate
and improve pedestal predictive models. This letter reports direct evidence of density and magnetic
fluctuations showing the stiff onset of an edge instability leading to the saturation of the pedestal on
the Alcator C-Mod tokamak. Linear stability and gyrokinetic analyses point to the edge pedestal
being kinetic ballooning unstable with wavenumber consistent with observations.
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Submitted to: Physical Review Letters (October 2013)
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Download PPPL-4984 (pdf 2.9 MB 5 pp)
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