Observation of edge instability limiting the pedestal growth in tokamak plasmas.

نویسندگان

  • A Diallo
  • J W Hughes
  • M Greenwald
  • B Labombard
  • E Davis
  • S-G Baek
  • C Theiler
  • P Snyder
  • J Canik
  • J Walk
  • T Golfinopoulos
  • J Terry
  • M Churchill
  • A Hubbard
  • M Porkolab
  • L Delgado-Aparicio
  • M L Reinke
  • A White
  • Alcator C-Mod Team
چکیده

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. Edge stability analyses indicate that the pedestal is unstable to both ballooning mode and kinetic ballooning mode in agreement with observations.

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عنوان ژورنال:
  • Physical review letters

دوره 112 11  شماره 

صفحات  -

تاریخ انتشار 2014