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

Journal Article · · Physical Review Letters
 [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)

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.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
FC02-99ER54512; SC0014264
OSTI ID:
1432046
Alternate ID(s):
OSTI ID: 1421579
Journal Information:
Physical Review Letters, Vol. 120, Issue 7; ISSN 0031-9007
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 27 works
Citation information provided by
Web of Science

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Cited By (7)

Main-ion intrinsic toroidal rotation across the ITG/TEM boundary in DIII-D discharges during ohmic and electron cyclotron heating journal April 2019
Predict-first experiments and modeling of perturbative cold pulses in the DIII-D tokamak journal June 2019
Dynamics of cold pulses induced by super-sonic molecular beam injection in the EAST tokamak journal March 2019
Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas journal May 2019
The local nature of the plasma response to cold pulses with electron and ion heating at ASDEX Upgrade journal August 2019
Hysteresis as a probe of turbulent bifurcation in intrinsic rotation reversals on Alcator C-Mod journal August 2019
Effect of the isotope mass on the turbulent transport at the edge of L-mode plasmas in ASDEX Upgrade and JET-ILW journal October 2019

Figures / Tables (5)