MHD precursor to high current disruptions in the TCV-tokamak
TCV (tokamak à configuration variable) has been designed to produce highly shaped plasmas. Elongated plasmas in particular show an improvement in confinement and allow for a higher plasma current. The plasma current that can be stably confined increases, as expected, with elongations up to kappa = 2.3. Attempts to increase the plasma current further led to disruptions which were preceded by MHD activity. Measurements with magnetic probes at the plasma edge and soft x-ray diodes reveal that a kink-type mode with a poloidal periodicity of m = 2 and a toroidal periodicity of n = 1 causes the disruption. This mode is often preceded by cascades of m/n = 4/3 and 3/2 modes. A comparison between experimental growth rates and resistive MHD calculations show good agreement.
Bibliographic Reference: Article: Proceedings of Frühjahrstagung 1998 der Schweizerische Physikalischen Gesellschaft (1998)
Record Number: 199810541 / Last updated on: 1998-05-05
Original language: en
Available languages: en