DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Simultaneous detection of neoclassical tearing mode and electron cyclotron current drive locations using electron cyclotron emission in DIII-D

Abstract

Accurate real-time measurements of magnetic island and electron cyclotron current drive (ECCD) locations are essential for efficient suppression of the neoclassical tearing mode (NTM). To determine these locations, many control systems rely on motional Stark effect constrained equilibria reconstruction and real-time Thomson scattering with TORBEAM current drive evaluation and therefore require time-intensive cross-calibration of at least two different diagnostics. Here we present a simpler, proof-of-concept analysis that uses only a single diagnostic (a radial array electron cyclotron emission radiometer) for the simultaneous determination of both the radial position of a magnetic island and the deposition location of ECCD. Measurements are compared with the modified Rutherford equation to demonstrate the effect of ECCD alignment on NTM suppression.

Authors:
ORCiD logo [1];  [2];  [3];  [2];  [4]
  1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. General Atomics, San Diego, CA (United States)
  3. Univ. of Texas, Austin, TX (United States)
  4. Princeton Univ., NJ (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
OSTI Identifier:
1511826
Alternate Identifier(s):
OSTI ID: 1562283
Grant/Contract Number:  
DC-AC02-09Ch11466, DE-AC52-07NA27344, DE-FC02-04ER54698, ED-AC05-00OR22725 and DE-FOA-0001386: Early Career Research Program.; FC02-04ER54698
Resource Type:
Accepted Manuscript
Journal Name:
Fusion Engineering and Design
Additional Journal Information:
Journal Volume: 141; Journal Issue: C; Journal ID: ISSN 0920-3796
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; NTM; Tokamak control; ECCD; ECE; DIII-D; Plasma; NTM Tokamak control ECCD ECE DIII-D Plasma

Citation Formats

Nelson, A. O., La Haye, R. J., Austin, M. E., Welander, A. S., and Kolemen, E. Simultaneous detection of neoclassical tearing mode and electron cyclotron current drive locations using electron cyclotron emission in DIII-D. United States: N. p., 2019. Web. doi:10.1016/j.fusengdes.2019.02.089.
Nelson, A. O., La Haye, R. J., Austin, M. E., Welander, A. S., & Kolemen, E. Simultaneous detection of neoclassical tearing mode and electron cyclotron current drive locations using electron cyclotron emission in DIII-D. United States. https://doi.org/10.1016/j.fusengdes.2019.02.089
Nelson, A. O., La Haye, R. J., Austin, M. E., Welander, A. S., and Kolemen, E. Tue . "Simultaneous detection of neoclassical tearing mode and electron cyclotron current drive locations using electron cyclotron emission in DIII-D". United States. https://doi.org/10.1016/j.fusengdes.2019.02.089. https://www.osti.gov/servlets/purl/1511826.
@article{osti_1511826,
title = {Simultaneous detection of neoclassical tearing mode and electron cyclotron current drive locations using electron cyclotron emission in DIII-D},
author = {Nelson, A. O. and La Haye, R. J. and Austin, M. E. and Welander, A. S. and Kolemen, E.},
abstractNote = {Accurate real-time measurements of magnetic island and electron cyclotron current drive (ECCD) locations are essential for efficient suppression of the neoclassical tearing mode (NTM). To determine these locations, many control systems rely on motional Stark effect constrained equilibria reconstruction and real-time Thomson scattering with TORBEAM current drive evaluation and therefore require time-intensive cross-calibration of at least two different diagnostics. Here we present a simpler, proof-of-concept analysis that uses only a single diagnostic (a radial array electron cyclotron emission radiometer) for the simultaneous determination of both the radial position of a magnetic island and the deposition location of ECCD. Measurements are compared with the modified Rutherford equation to demonstrate the effect of ECCD alignment on NTM suppression.},
doi = {10.1016/j.fusengdes.2019.02.089},
journal = {Fusion Engineering and Design},
number = C,
volume = 141,
place = {United States},
year = {Tue Feb 26 00:00:00 EST 2019},
month = {Tue Feb 26 00:00:00 EST 2019}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 6 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Observation of Nonlinear Neoclassical Pressure-Gradient–Driven Tearing Modes in TFTR
journal, June 1995


Stabilization and prevention of the 2/1 neoclassical tearing mode for improved performance in DIII-D
journal, April 2007


Heating and current drive by electron cyclotron waves
journal, May 2004


Neoclassical tearing modes and their control
journal, May 2006


Real-time determination of magnetic island location for neoclassical tearing mode control in DIII-D
journal, August 2006


Advanced techniques for neoclassical tearing mode control in DIII-D
journal, October 2009

  • Volpe, F. A. G.; Austin, M. E.; La Haye, R. J.
  • Physics of Plasmas, Vol. 16, Issue 10
  • DOI: 10.1063/1.3232325

Real-time control of tearing modes using a line-of-sight electron cyclotron emission diagnostic
journal, September 2010


The ECRH/ECCD system on Tore Supra, a major step towards continuous operation
journal, November 2003


Integrated real-time control of MHD instabilities using multi-beam ECRH/ECCD systems on TCV
journal, July 2012


Experiment and simulation of tearing mode evolution with electron cyclotron current drive in KSTAR
journal, April 2015


Overview of equilibrium reconstruction on DIII-D using new measurements from an expanded motional Stark effect diagnostic
journal, October 2008

  • Holcomb, C. T.; Makowski, M. A.; Allen, S. L.
  • Review of Scientific Instruments, Vol. 79, Issue 10
  • DOI: 10.1063/1.2955711

TORBEAM, a beam tracing code for electron-cyclotron waves in tokamak plasmas
journal, May 2001


Electron cyclotron emission radiometer upgrade on the DIII-D tokamak
journal, March 2003

  • Austin, M. E.; Lohr, J.
  • Review of Scientific Instruments, Vol. 74, Issue 3
  • DOI: 10.1063/1.1530387

Technological challenges of ITER diagnostics
journal, November 2005


Disruption avoidance through the prevention of NTM destabilization in TCV
journal, August 2018


Discharge improvement through control of neoclassical tearing modes by localized ECCD in DIII-D
journal, September 2003


A frequency tunable, eight-channel correlation ECE system for electron temperature turbulence measurements on the DIII-D tokamak
journal, August 2016

  • Sung, C.; Peebles, W. A.; Wannberg, C.
  • Review of Scientific Instruments, Vol. 87, Issue 11
  • DOI: 10.1063/1.4961296

Dimensionless scaling of the critical beta for onset of a neoclassical tearing mode
journal, August 2000

  • La Haye, R. J.; Buttery, R. J.; Guenter, S.
  • Physics of Plasmas, Vol. 7, Issue 8
  • DOI: 10.1063/1.874199

Control of neoclassical tearing modes in DIII–D
journal, May 2002

  • La Haye, R. J.; Günter, S.; Humphreys, D. A.
  • Physics of Plasmas, Vol. 9, Issue 5
  • DOI: 10.1063/1.1456066

Complete suppression of the m = 2/ n = 1 neoclassical tearing mode using electron cyclotron current drive in DIII-D
journal, January 2004


Neoclassical tearing modes in Tokamak Fusion Test Reactor experiments. I. Measurements of magnetic islands and Δ
journal, April 1998

  • Chang, Z.; Fredrickson, E. D.; Batha, S. H.
  • Physics of Plasmas, Vol. 5, Issue 4
  • DOI: 10.1063/1.872627

Works referencing / citing this record:

Electron cyclotron emission based q -profile measurement and concept for equilibrium reconstruction
journal, June 2019

  • Nelson, A. O.; Austin, M. E.; Kolemen, E.
  • Plasma Physics and Controlled Fusion, Vol. 61, Issue 8
  • DOI: 10.1088/1361-6587/ab24a4