Magnetic surface topology in decaying plasma knots
Torus-knot solitons have recently been formulated as solutions to the ideal incompressible magnetohydrodynamics (MHD) equations. We investigate numerically how these fields evolve in resistive, compressible, and viscous MHD. We find that certain decaying plasma torus knots exhibit magnetic surfaces...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2017-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/aa5de6 |
| _version_ | 1797750862986084352 |
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| author | C B Smiet A Thompson P Bouwmeester D Bouwmeester |
| author_facet | C B Smiet A Thompson P Bouwmeester D Bouwmeester |
| author_sort | C B Smiet |
| collection | DOAJ |
| description | Torus-knot solitons have recently been formulated as solutions to the ideal incompressible magnetohydrodynamics (MHD) equations. We investigate numerically how these fields evolve in resistive, compressible, and viscous MHD. We find that certain decaying plasma torus knots exhibit magnetic surfaces that are topologically distinct from a torus. The evolution is predominantly determined by a persistent zero line in the field present when the poloidal winding number ${n}_{{\rm{p}}}\ne 1$ . Dependence on the toroidal winding number n _t is less pronounced as the zero line induced is contractible and disappears. The persistent zero line intersects the new magnetic surfaces such that, through the Hopf–Poincaré index theorem, the sum of zeroes on the new surfaces equals their (in general non-zero) Euler characteristic. Furthermore we observe the formation of magnetic islands between the surfaces. These novel persistent magnetic structures are of interest for plasma confinement, soliton dynamics and the study of dynamical systems in general. |
| first_indexed | 2024-03-12T16:38:59Z |
| format | Article |
| id | doaj.art-e7171007a460489e997110dbd1958c4c |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:38:59Z |
| publishDate | 2017-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-e7171007a460489e997110dbd1958c4c2023-08-08T14:37:06ZengIOP PublishingNew Journal of Physics1367-26302017-01-0119202304610.1088/1367-2630/aa5de6Magnetic surface topology in decaying plasma knotsC B Smiet0A Thompson1P Bouwmeester2D Bouwmeester3Huygens-Kamerlingh Onnes Laboratory, Leiden University , PO Box 9504, 2300 RA Leiden, The NetherlandsDepartment of Physics, University of California Santa Barbara , Santa Barbara, CA 93106, United States of AmericaHuygens-Kamerlingh Onnes Laboratory, Leiden University , PO Box 9504, 2300 RA Leiden, The NetherlandsHuygens-Kamerlingh Onnes Laboratory, Leiden University , PO Box 9504, 2300 RA Leiden, The Netherlands; Department of Physics, University of California Santa Barbara , Santa Barbara, CA 93106, United States of AmericaTorus-knot solitons have recently been formulated as solutions to the ideal incompressible magnetohydrodynamics (MHD) equations. We investigate numerically how these fields evolve in resistive, compressible, and viscous MHD. We find that certain decaying plasma torus knots exhibit magnetic surfaces that are topologically distinct from a torus. The evolution is predominantly determined by a persistent zero line in the field present when the poloidal winding number ${n}_{{\rm{p}}}\ne 1$ . Dependence on the toroidal winding number n _t is less pronounced as the zero line induced is contractible and disappears. The persistent zero line intersects the new magnetic surfaces such that, through the Hopf–Poincaré index theorem, the sum of zeroes on the new surfaces equals their (in general non-zero) Euler characteristic. Furthermore we observe the formation of magnetic islands between the surfaces. These novel persistent magnetic structures are of interest for plasma confinement, soliton dynamics and the study of dynamical systems in general.https://doi.org/10.1088/1367-2630/aa5de6magnetic topologymagnetic helicitymagnetic reconnectiontopological solitons52.65.-y52.35.Vd |
| spellingShingle | C B Smiet A Thompson P Bouwmeester D Bouwmeester Magnetic surface topology in decaying plasma knots New Journal of Physics magnetic topology magnetic helicity magnetic reconnection topological solitons 52.65.-y 52.35.Vd |
| title | Magnetic surface topology in decaying plasma knots |
| title_full | Magnetic surface topology in decaying plasma knots |
| title_fullStr | Magnetic surface topology in decaying plasma knots |
| title_full_unstemmed | Magnetic surface topology in decaying plasma knots |
| title_short | Magnetic surface topology in decaying plasma knots |
| title_sort | magnetic surface topology in decaying plasma knots |
| topic | magnetic topology magnetic helicity magnetic reconnection topological solitons 52.65.-y 52.35.Vd |
| url | https://doi.org/10.1088/1367-2630/aa5de6 |
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