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Title: Observation of a Multimode Plasma Response and its Relationship to Density Pumpout and Edge-Localized Mode Suppression

Journal Article · · Physical Review Letters
 [1];  [2];  [3];  [2];  [1];  [1];  [4];  [1];  [1];  [5];  [2];  [2];  [6];  [2]
  1. General Atomics, San Diego, CA (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  3. Australian National Univ., Canberra, ACT (Australia). Plasma Research Lab.
  4. Columbia Univ., New York, NY (United States)
  5. Univ. of California, San Diego, CA (United States)
  6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Density pumpout and edge-localized mode (ELM) suppression by applied n=2 magnetic fields in low collisionality DIII-D plasmas are shown to be correlated with the magnitude of the plasma response driven on the high field side (HFS) of the magnetic axis, but not the low-field side (LFS) midplane. These distinct responses are a direct measurement of a multi-modal magnetic plasma response, with each structure preferentially excited by a different n=2 applied spectrum and preferentially detected on the LFS or HFS. Ideal and resistive MHD calculations find that the LFS measurement is primarily sensitive to excitation of stable kink modes, while the HFS measurement is primarily sensitive to resonant currents (whether fully shielding or partially penetrated). Lastly, the resonant currents are themselves strongly modified by kink excitation, with the optimal applied field pitch for pumpout and ELM suppression significantly differing from equilibrium field-alignment.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); General Atomics, San Diego, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES); USDOE Office of Nuclear Energy (NE)
Grant/Contract Number:
AC05-00OR22725; FC02-04ER54698; AC02-09CH11466; FG02-04ER54761; AC05-06OR23100; SC0001961
OSTI ID:
1295122
Alternate ID(s):
OSTI ID: 1180288; OSTI ID: 1329636
Journal Information:
Physical Review Letters, Vol. 114, Issue 10; ISSN 0031-9007
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 107 works
Citation information provided by
Web of Science

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Cited By (37)

3D field phase-space control in tokamak plasmas journal September 2018
Comparative investigation of ELM control based on toroidal modelling of plasma response to RMP fields journal May 2017
Dynamic divertor control using resonant mixed toroidal harmonic magnetic fields during ELM suppression in DIII-D journal May 2018
Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling journal May 2018
Modal analysis of the full poloidal structure of the plasma response to n = 2 magnetic perturbations journal July 2018
Conceptual design of extended magnetic probe set to improve 3D field detection in NSTX-U journal October 2018
Screening of resonant magnetic perturbation fields by poloidally varying toroidal plasma rotation journal August 2018
Mode penetration induced by transient magnetic perturbations journal August 2018
Non-linear modeling of the threshold between ELM mitigation and ELM suppression by resonant magnetic perturbations in ASDEX upgrade journal April 2019
The density dependence of edge-localized-mode suppression and pump-out by resonant magnetic perturbations in the DIII-D tokamak journal December 2019
Modelling plasma response to RMP fields in ASDEX Upgrade with varying edge safety factor and triangularity journal September 2016
Equilibrium drives of the low and high field side n   =  2 plasma response and impact on global confinement journal April 2016
Non-linear modeling of the plasma response to RMPs in ASDEX Upgrade journal September 2016
ELM control with RMP: plasma response models and the role of edge peeling response journal October 2016
Modelling of plasma response to 3D external magnetic field perturbations in EAST journal October 2016
Toroidal modeling of plasma response to RMP fields in ITER journal February 2017
Effect of rotation zero-crossing on single-fluid plasma response to three-dimensional magnetic perturbations journal February 2017
Dynamics of ideal modes and subsequent ELM crashes in 3D tokamak geometry from external magnetic perturbations journal November 2018
Characterisation of the fast-ion edge resonant transport layer induced by 3D perturbative fields in the ASDEX Upgrade tokamak through full orbit simulations journal November 2018
Magnetic polarization measurements of the multi-modal plasma response to 3D fields in the EAST tokamak journal May 2018
Toroidal plasma response based ELM control coil design for EU DEMO journal June 2018
Grassy-ELM regime with edge resonant magnetic perturbations in fully noninductive plasmas in the DIII-D tokamak journal July 2018
Investigation of RMP induced density pump-out on EAST journal October 2018
Plasma response to rotating resonant magnetic perturbations with a locked mode in the J-TEXT tokamak journal January 2019
Edge localized mode suppression and plasma response using mixed toroidal harmonic resonant magnetic perturbations in DIII-D journal January 2019
Identification of multiple eigenmode growth rates in DIII-D and EAST tokamak plasmas journal January 2019
Effects of RMP-induced changes of radial electric fields on microturbulence in DIII-D pedestal top journal February 2019
The effect of plasma shape and neutral beam mix on the rotation threshold for RMP-ELM suppression journal March 2019
Impact of n   =  1 field on the non-axisymmetric magnetic perturbations associated with the edge localized mode crashes in the ASDEX Upgrade tokamak journal March 2019
Resistive versus ideal plasma response to RMP fields in DIII-D: roles of q 95 and X-point geometry journal June 2019
Modeling 3D plasma boundary corrugation and tailoring toroidal torque profiles with resonant magnetic perturbation fields in ITER journal August 2019
Toroidal modeling of resonant magnetic perturbations in preparation for the initial phase of ITER operation journal November 2019
A new criterion for controlling edge localized modes based on a multi-mode plasma response journal October 2019
Nonlinear modeling of the effect of n   =  2 resonant magnetic field perturbation on peeling-ballooning modes in KSTAR journal January 2020
Pedestal Bifurcation and Resonant Field Penetration at the Threshold of Edge-Localized Mode Suppression in the DIII-D Tokamak journal March 2015
Nonlinear Transition from Mitigation to Suppression of the Edge Localized Mode with Resonant Magnetic Perturbations in the EAST Tokamak journal September 2016
ELM control with RMP: plasma response models and the role of edge peeling response text January 2016