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Title: Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions

Abstract

The evolution of the magnetic topology between the outer separatrix of a large m = 2/ n = 1 island ( m and n: poloidal and toroidal numbers) and the last closed flux surface after mode locking is, for the first time, directly measured. Edge locked island chains with multiple helicity and very narrow widths are discovered to be destabilized and govern the cooling process in the plasma peripheral region. Furthermore, these edge small nonrotating islands are initially well separated from the 2/1 island, leading to a long quasistationary phase, but later trigger thermal quench immediately after they start to overlap with the 2/1 island, producing a broad stochastic layer deep into the plasma midradius.

Authors:
 [1];  [2]; ORCiD logo [3]; ORCiD logo [1];  [1];  [4]; ORCiD logo [4]
  1. General Atomics, San Diego, CA (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  4. National Inst. for Fusion Science, Toki (Japan)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); U.S. Department of Energy; U.S. Dept. of Energy
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1559020
Alternate Identifier(s):
OSTI ID: 1507195; OSTI ID: 1567846; OSTI ID: 1572193
Grant/Contract Number:  
AC02-09CH11466; AC05-00OR22725; FC02-04ER54698; SC0015878; AC02- 09CH11466
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 26; Journal Issue: 4; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Du, X. D., Shafer, M. W., Hu, Q. M., Evans, T. E., Strait, E. J., Ohdachi, S., and Suzuki, Y. Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions. United States: N. p., 2019. Web. doi:10.1063/1.5085329.
Du, X. D., Shafer, M. W., Hu, Q. M., Evans, T. E., Strait, E. J., Ohdachi, S., & Suzuki, Y. Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions. United States. doi:10.1063/1.5085329.
Du, X. D., Shafer, M. W., Hu, Q. M., Evans, T. E., Strait, E. J., Ohdachi, S., and Suzuki, Y. Mon . "Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions". United States. doi:10.1063/1.5085329.
@article{osti_1559020,
title = {Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions},
author = {Du, X. D. and Shafer, M. W. and Hu, Q. M. and Evans, T. E. and Strait, E. J. and Ohdachi, S. and Suzuki, Y.},
abstractNote = {The evolution of the magnetic topology between the outer separatrix of a large m = 2/n = 1 island (m and n: poloidal and toroidal numbers) and the last closed flux surface after mode locking is, for the first time, directly measured. Edge locked island chains with multiple helicity and very narrow widths are discovered to be destabilized and govern the cooling process in the plasma peripheral region. Furthermore, these edge small nonrotating islands are initially well separated from the 2/1 island, leading to a long quasistationary phase, but later trigger thermal quench immediately after they start to overlap with the 2/1 island, producing a broad stochastic layer deep into the plasma midradius.},
doi = {10.1063/1.5085329},
journal = {Physics of Plasmas},
number = 4,
volume = 26,
place = {United States},
year = {2019},
month = {4}
}

Journal Article:
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This content will become publicly available on April 15, 2020
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