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(TH/P2-06) Long-Wavelength Instability of Periodic Flows and Whistler Waves in Electron Magnetohydrodynamics

V.P. Lakhin¹⁾, V.D. Levchenko^2
 
1) RRC ``Kurchatov Institute'', Nuclear Fusion Institute, Moscow, Russia
²⁾ M.V. Keldysh Institute of Applied Mathematics, Moscow, Russia

Abstract.  It is known that at some critical amplitude both periodic flows in fluids and the drift waves in magnetized plasma become unstable with respect to long-wavelength perturbations. Such secondary instabilities result in the generation of large-scale structures which play a significant role in such important physical phenomena as an enhanced transport and self-organization. In z-pinches, plasma erosion switches, and possibly in tokamaks with an intensive ECR heating the phenomena on small time and space scales when only the electron motions play a role and the ions form an immobile background could be important. In the present report stability analysis of periodic flows and whistler waves with respect to long-wavelength perturbations within the framework of dissipative electron magnetohydrodynamics is presented. Several types of flows (non-helical, isotropic helical, and anisotropic helical) and whistler waves are considered. It is shown that the destabilizing effect on the long-wavelength perturbations is due to either flow anisotropy (the negative resistivity effect) or its helicity.

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