Finite Larmor-radius theory of magnetic island evolution
United Kingdom
The role of polarization current in magnetic island evolution
United Kingdom
Finite Larmor-radius theory of magnetic island evolution
In this paper, we present the first kinetic analysis of nonlinear magnetic island evolution that includes the effect of the excitation of drift waves and extends over the complete range of frequencies comparable to the drift frequency. Our analysis brings to light three new phenomena that have important implications for our understanding of island ...
The role of polarization current in magnetic island evolution
The polarization current plays an important role in the evolution of magnetic islands with a width comparable to the characteristic ion orbit width. Understanding the evolution of such small magnetic islands is important for two reasons: (1) to investigate the threshold mechanisms for growth of large-scale islands (e.g. neoclassical tearing modes),...
The effect of magnetic field geometry on viscous damping of rotation in stellarators
SIGLE / Available from TIB Hannover: RA 71(2/334) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische Informationsbibliothek / DE / Germany
The effect of magnetic field geometry on viscous damping of rotation in stellarators
Germany
Investigation of tearing modes in asymmetric elongated plasmas in the ASDEX upgrade tokamak
Germany
Investigation of tearing modes in asymmetric elongated plasmas in the ASDEX upgrade tokamak
MHD modes always occur in ASDEX Upgrade before q-limit and density limit disruptions. The modulation of the poloidal field due to rotating islands is measured by a poloidal array of 30 pick up coils and by 4 coils in a toroidal plane. For a detailed analysis of the modes the Mirnov probe measurements are compared with simulations of the perturbativ...
Resonant interaction of energetic ions with Alfven-like perturbations in stellarators
The modification of passing guiding center orbits of 3.5 MeV alpha particles and 45 keV protons in the presence of global Alfven eigenmodes (GAE's) is studied in modular advanced stellarators. It is found that if resonances between particles and waves occur, drift surfaces form a set of island structures. The mode numbers of the perturbations, whic...
Resonant interaction of energetic ions with Alfven-like perturbations in stellarators
Germany
