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Title: Explaining Cold-Pulse Dynamics in Tokamak Plasmas Using Local Turbulent Transport Models

Abstract

A long-standing enigma in plasma transport has been resolved by modeling of cold-pulse experiments conducted on the Alcator C-Mod tokamak. Controlled edge cooling of fusion plasmas triggers core electron heating on time scales faster than an energy confinement time, which has long been interpreted as strong evidence of nonlocal transport. Here, this Letter shows that the steady-state profiles, the cold-pulse rise time, and disappearance at higher density as measured in these experiments are successfully captured by a recent local quasilinear turbulent transport model, demonstrating that the existence of nonlocal transport phenomena is not necessary for explaining the behavior and time scales of cold-pulse experiments in tokamak plasmas.

Authors:
 [1];  [2];  [2];  [3];  [4];  [2];  [3];  [2];  [2];  [2];  [2];  [2];  [2];  [2]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Cente
  3. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  4. General Atomics, San Diego, CA (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1432046
Alternate Identifier(s):
OSTI ID: 1421579
Grant/Contract Number:  
FC02-99ER54512; SC0014264
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 120; Journal Issue: 7; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Staebler, G. M., Rice, J. E., Yuan, X., Cao, N. M., Creely, A. J., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., and Sciortino, F. Explaining Cold-Pulse Dynamics in Tokamak Plasmas Using Local Turbulent Transport Models. United States: N. p., 2018. Web. doi:10.1103/PhysRevLett.120.075001.
Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Staebler, G. M., Rice, J. E., Yuan, X., Cao, N. M., Creely, A. J., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., & Sciortino, F. Explaining Cold-Pulse Dynamics in Tokamak Plasmas Using Local Turbulent Transport Models. United States. doi:10.1103/PhysRevLett.120.075001.
Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Staebler, G. M., Rice, J. E., Yuan, X., Cao, N. M., Creely, A. J., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., and Sciortino, F. Fri . "Explaining Cold-Pulse Dynamics in Tokamak Plasmas Using Local Turbulent Transport Models". United States. doi:10.1103/PhysRevLett.120.075001. https://www.osti.gov/servlets/purl/1432046.
@article{osti_1432046,
title = {Explaining Cold-Pulse Dynamics in Tokamak Plasmas Using Local Turbulent Transport Models},
author = {Rodriguez-Fernandez, P. and White, A. E. and Howard, N. T. and Grierson, B. A. and Staebler, G. M. and Rice, J. E. and Yuan, X. and Cao, N. M. and Creely, A. J. and Greenwald, M. J. and Hubbard, A. E. and Hughes, J. W. and Irby, J. H. and Sciortino, F.},
abstractNote = {A long-standing enigma in plasma transport has been resolved by modeling of cold-pulse experiments conducted on the Alcator C-Mod tokamak. Controlled edge cooling of fusion plasmas triggers core electron heating on time scales faster than an energy confinement time, which has long been interpreted as strong evidence of nonlocal transport. Here, this Letter shows that the steady-state profiles, the cold-pulse rise time, and disappearance at higher density as measured in these experiments are successfully captured by a recent local quasilinear turbulent transport model, demonstrating that the existence of nonlocal transport phenomena is not necessary for explaining the behavior and time scales of cold-pulse experiments in tokamak plasmas.},
doi = {10.1103/PhysRevLett.120.075001},
journal = {Physical Review Letters},
number = 7,
volume = 120,
place = {United States},
year = {2018},
month = {2}
}

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Free Publicly Available Full Text
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Cited by: 4 works
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Figures / Tables:

FIG. 1 FIG. 1: Experimental parameters. (a) Plasma current, toroidal field and LBO injection times; (b) line-averaged density and total radiated power normalized to pre-cold pulses time; (c) core and edge electron and ion temperatures. Details on diagnostic systems can be found in Refs. [11, 27].

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