Nonlinear resonant absorption of fast magnetoacoustic waves in strongly anisotropic and dispersive plasmas |
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Istvan Ballai Submitted: 2009-03-05 04:02
The nonlinear theory of driven magnetohydrodynamics (MHD) waves in strongly anisotropic and dispersive
plasmas, developed for slow resonance by Clack and Ballai [Phys. Plasmas 15(8),
2310 (2008)] and Alfvén resonance by Clack et al. [A&A 494, 317 (2009)],
is used to study the weakly nonlinear interaction of
fast magnetoacoustic (FMA) waves in a one-dimensional planar plasma.
The magnetic configuration consists of an
inhomogeneous magnetic slab sandwiched between two regions of
semi-infinite homogeneous magnetic plasmas. Laterally driven FMA
waves penetrate the inhomogeneous slab interacting with the
localized slow or Alfvén dissipative layer and are partly
reflected, dissipated and transmitted by this region. The
nonlinearity parameter defined by Clack and Ballai (2008) is assumed
to be small and a regular perturbation method is used to obtain
analytical solutions in the slow dissipative layer. The effect of
dispersion in the slow dissipative layer is to further decrease the
coefficient of energy absorption, compared to its standard weakly
nonlinear counterpart, and the generation of higher harmonics in the
outgoing wave in addition to the fundamental one. The absorption of external drivers
at the Alfvén resonance is described within the linear MHD with great accuracy.
Authors: C.T.M. Clack, I. Ballai
Projects:
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Publication Status: Physics of Plasmas, accepted
Last Modified: 2010-06-16 11:19
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