Bifurcations and control of chaos in wave-particle interactions
Transport of magnetic field lines and particles in tokamaks and plasma modeling fo...
| Full text | |
| Author(s): |
Fraile, Andre C.
;
Roberto, Marisa
;
Canal, Gustavo P.
;
Caldas, Ibere L.
Total Authors: 4
|
| Document type: | Journal article |
| Source: | Physics of Plasmas; v. 31, n. 7, p. 11-pg., 2024-07-01. |
| Abstract | |
On a rational magnetic surface, an isochronous bifurcation transforms one island chain into another chain with the same winding number. This transformation has been the subject of recent studies in tokamak plasmas. Namely, visco-resistive magnetohydrodynamic simulations of NSTX-U and DIII-D plasmas showed the onset of bifurcations with new magnetic isochronous islands for two competing helical perturbations on the same rational magnetic surface. To investigate these bifurcations, we use a cylindrical plasma model, with first-order correction for toroidicity, subject to externally applied magnetic perturbations, generated by a pair of resonant helical windings (RHWs) on the external wall and superposed to a helical current sheet (HCS) located on a rational plasma surface. We numerically integrate the magnetic field line equation and show that isochronous islands emerge when the perturbation created by the HCS increases. We present examples of such bifurcations on primary and secondary magnetic surfaces for different RHW configurations. (AU) | |
| FAPESP's process: | 22/08699-2 - Chaotic transport in tokamak plasmas |
| Grantee: | Marisa Roberto |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 18/03211-6 - Non linear dynamics |
| Grantee: | Iberê Luiz Caldas |
| Support Opportunities: | Research Projects - Thematic Grants |