"Snowflake" H mode in a tokamak plasma.

نویسندگان

  • F Piras
  • S Coda
  • B P Duval
  • B Labit
  • J Marki
  • S Yu Medvedev
  • J-M Moret
  • A Pitzschke
  • O Sauter
چکیده

An edge-localized mode (ELM) H-mode regime, supported by electron cyclotron heating, has been successfully established in a "snowflake" (second-order null) divertor configuration for the first time in the TCV tokamak. This regime exhibits 2 to 3 times lower ELM frequency and 20%-30% increased normalized ELM energy (ΔWELM/Wp) compared to an identically shaped, conventional single-null diverted H mode. Enhanced stability of mid- to high-toroidal-mode-number ideal modes is consistent with the different snowflake ELM phenomenology. The capability of the snowflake to redistribute the edge power on the additional strike points has been confirmed experimentally.

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عنوان ژورنال:
  • Physical review letters

دوره 105 15  شماره 

صفحات  -

تاریخ انتشار 2010