Sub-microsecond Temporal Evolution of Edge Density During Edge Localized Modes in KSTAR Tokamak Plasmas Inferred from Ion Cyclotron Emission

Sub-microsecond Temporal Evolution of Edge Density During Edge Localized Modes in KSTAR Tokamak Plasmas Inferred from Ion Cyclotron Emission

Sub-microsecond Temporal Evolution of Edge Density During Edge Localized Modes in KSTAR Tokamak Plasmas Inferred from Ion Cyclotron Emission 150 150 Mathew
CCFE-PR(17)04

Sub-microsecond Temporal Evolution of Edge Density During Edge Localized Modes in KSTAR Tokamak Plasmas Inferred from Ion Cyclotron Emission

Ion cyclotron emission (ICE) is detected during edge localised modes (ELMs) in the KSTAR tokamak at harmonics of the proton cyclotron frequency in the outer plasma edge. The emission typically chirps downward (occasionally upward) during ELM crashes, and is driven by confined 3MeV fusion-born protons that have large drift excursions from the plasma core. We exploit fully kinetic simulations at multiple plasma densities to match the time-evolving features of the chirping ICE. This yields a unique, very high time resolution ( < 1 _s ) diagnostic of the collapsing edge pedestal density.

Collection:
Journals
Journal:
Nuclear Fusion
Publisher:
IOP
Published date:
10/01/2017