Dephasing and Phase-Pinning: Dual Role of Radial Electric Field in Edge MHD Dynamics of Toroidally Confined Plasmas

ORAL

Abstract

We propose a new understanding of how the radial electric field ($E_r$) impacts the edge magnetohydrodynamic (MHD) instabilities. The analysis uncovered that $E_r$-shear stabilizes the Peeling-Ballooning modes, while $E_r$-curvature destabilizes the low-n kink/peeling modes. The underlying physical mechanism is that the perturbed radial velocity and displacement become stronger dephasing or phase pinning. More specifically, the ratio of $E_r$-curvature to $E_r$-shear could be measured to quantify their relative competition strength.

–

Authors

  • Yi Zhang

    State Key Laboratory of Nuclear Physics and Technology, Fusion Simulation Center, School of Physics, Peking University, Beijing 100871, China

  • Zhibin Guo

    State Key Laboratory of Nuclear Physics and Technology, Fusion Simulation Center, School of Physics, Peking University, Beijing 100871, China

  • Patrick Diamond

    University of California, San Diego, University of California San Diego, La Jolla, California 92093, USA