Homoclinic tangles in the DIIID tokamak from the map equations in natural canonical coordinates*
Abstract
Trajectories of magnetic field lines are a 1½ degree of freedom Hamiltonian system. The unperturbed separatrix and the perturbed separatrix in a divertor tokamak are fundamentally different. Magnetic asymmetries cause the separatrix to form extremely complicated structures known as homoclinic tangles. After each toroidal circuit, the perturbed separatrix manifolds meet in a fixed poloidal plane and intersect to form homoclinic tangle in order to preserve the topological invariants. This tangle becomes extremely complicated as the magnetic field lines take more and more toroidal turns. This effect is most pronounced near the Xpoint. The homoclinic tangles of the DIIID tokamak separatrix from the magnetic perturbation representing the peelingballooning modes are studied. The homoclinic tangles can have important implications for the edge physics in divertor tokamaks.
 Authors:

 Hampton Univ., Hampton, VA (United States). Department of Mathematics
 Columbia Univ., New York, NY (United States). Dept. of Applied Physics and Applied Mathematics
 Publication Date:
 Research Org.:
 Lawrence Berkeley National LaboratoryNational Energy Research Scientific Computing Center
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1523276
 DOE Contract Number:
 AC0205CH11231
 Resource Type:
 Journal Article
 Journal Name:
 Radiation Effects and Defects in Solids
 Additional Journal Information:
 Journal Volume: 172; Journal Issue: 12; Journal ID: ISSN 10420150
 Country of Publication:
 United States
 Language:
 English
Citation Formats
Punjabi, Alkesh, and Boozer, Allen. Homoclinic tangles in the DIIID tokamak from the map equations in natural canonical coordinates*. United States: N. p., 2017.
Web. doi:10.1080/10420150.2017.1290632.
Punjabi, Alkesh, & Boozer, Allen. Homoclinic tangles in the DIIID tokamak from the map equations in natural canonical coordinates*. United States. doi:10.1080/10420150.2017.1290632.
Punjabi, Alkesh, and Boozer, Allen. Wed .
"Homoclinic tangles in the DIIID tokamak from the map equations in natural canonical coordinates*". United States. doi:10.1080/10420150.2017.1290632.
@article{osti_1523276,
title = {Homoclinic tangles in the DIIID tokamak from the map equations in natural canonical coordinates*},
author = {Punjabi, Alkesh and Boozer, Allen},
abstractNote = {Trajectories of magnetic field lines are a 1½ degree of freedom Hamiltonian system. The unperturbed separatrix and the perturbed separatrix in a divertor tokamak are fundamentally different. Magnetic asymmetries cause the separatrix to form extremely complicated structures known as homoclinic tangles. After each toroidal circuit, the perturbed separatrix manifolds meet in a fixed poloidal plane and intersect to form homoclinic tangle in order to preserve the topological invariants. This tangle becomes extremely complicated as the magnetic field lines take more and more toroidal turns. This effect is most pronounced near the Xpoint. The homoclinic tangles of the DIIID tokamak separatrix from the magnetic perturbation representing the peelingballooning modes are studied. The homoclinic tangles can have important implications for the edge physics in divertor tokamaks.},
doi = {10.1080/10420150.2017.1290632},
journal = {Radiation Effects and Defects in Solids},
issn = {10420150},
number = 12,
volume = 172,
place = {United States},
year = {2017},
month = {2}
}
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