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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 = {2019},
month = {2}
}

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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