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Title: Impact of punctual flat magnetic shear on the field line transport

Abstract

We investigate the magnetic field line transport for tokamak equilibria with monotonic magnetic shear perturbed by resonant fields. We show that when the local profile is flat at the plasma edge a transport barrier can be created leading to a field line transport reduction. This transport reduction is due to the field lines topological modifications, caused by a local flattened profile that reduces the global field lines escape pattern. The results are obtained by applying a symplectic map that describes perturbed magnetic field lines in large aspect ratio tokamaks.

Authors:
 [1];  [2];  [3]
  1. Department of Mathematics IMTec, Universidade Federal de Goás, 75704-020 Catalão (Brazil)
  2. (Brazil)
  3. Physics Institute, Universidade de São Paulo, 05315-970 São Paulo (Brazil)
Publication Date:
OSTI Identifier:
22490933
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ASPECT RATIO; EDGE LOCALIZED MODES; MAGNETIC FIELDS; PLASMA; SHEAR; TOKAMAK DEVICES; TOPOLOGY

Citation Formats

Abud, C. V., E-mail: cabud@ufg.br, Physics Institute, Universidade de São Paulo, 05315-970 São Paulo, and Caldas, I. L., E-mail: ibere@if.usp.br. Impact of punctual flat magnetic shear on the field line transport. United States: N. p., 2015. Web. doi:10.1063/1.4923016.
Abud, C. V., E-mail: cabud@ufg.br, Physics Institute, Universidade de São Paulo, 05315-970 São Paulo, & Caldas, I. L., E-mail: ibere@if.usp.br. Impact of punctual flat magnetic shear on the field line transport. United States. doi:10.1063/1.4923016.
Abud, C. V., E-mail: cabud@ufg.br, Physics Institute, Universidade de São Paulo, 05315-970 São Paulo, and Caldas, I. L., E-mail: ibere@if.usp.br. Mon . "Impact of punctual flat magnetic shear on the field line transport". United States. doi:10.1063/1.4923016.
@article{osti_22490933,
title = {Impact of punctual flat magnetic shear on the field line transport},
author = {Abud, C. V., E-mail: cabud@ufg.br and Physics Institute, Universidade de São Paulo, 05315-970 São Paulo and Caldas, I. L., E-mail: ibere@if.usp.br},
abstractNote = {We investigate the magnetic field line transport for tokamak equilibria with monotonic magnetic shear perturbed by resonant fields. We show that when the local profile is flat at the plasma edge a transport barrier can be created leading to a field line transport reduction. This transport reduction is due to the field lines topological modifications, caused by a local flattened profile that reduces the global field lines escape pattern. The results are obtained by applying a symplectic map that describes perturbed magnetic field lines in large aspect ratio tokamaks.},
doi = {10.1063/1.4923016},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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