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[en] A general theory for coupling between MHD waves obliquely incident on a stratified medium is developed. Coupling between the Alfven mode and the magnetoacoustic mode (the fast mode for upsilonsub(A) > csub(s) and the slow mode for upsilonsub(A) < csub(s) is affected little by the finiteness of csub(s)/upsilonsub(A) for upsilonsub(A) >> csub(s), and the coupling becomes weakers as csub(s)/ upsilonsub(A) is increased towards unity. Coupling between the fast and slow modes for upsilonsub(A) approximately equal to csub(s) is discussed qualitatively using solutions of the MHD counterpart of the Booker quartic equation. (Author)

[en] The 'hairy ball' model of coronal magnetic fields has a spherical source surface separating potential and radial magnetic fields. In the present model the source surface is chosen such that the wind speed equals the Alfvenic speed at selected points on the source surface. Results have been obtained for a dipole base field and an isothermal corona. (orig.)

[en] The vortex structures for the short-length drift Alfven waves in magnetized plasmas are investigated. the turbulence spectra of plasma vortex are estimated, and the anomalous diffusion coefficient is found using the dynamic model of plasma gas. The results show that the anomalous diffusion coefficient caused by the vortex turbulence is proportional to the square of the potential amplitude of the perturbation

[en] The time-independent transverse magnetic field that is generated via the nonlinear mixing of linear Alfven waves is examined in the vicinity of the Alfven resonance surface. It is shown that this magnetic field is unidirectional, and it is confined within a narrow layer. The position of the layer along with the amplitude and direction of the magnetic field within it can be controlled by means of the primary wave frequency, wave numbers, and amplitude. Combinations of these magnetized layers can, therefore, be used for the modification or synthesis of transverse magnetic fields

[en] One of the important and interesting processes in an electrically conducting gas is the sound propagation in the presence of magnetic field. The character of propagation depends essentially on the magnetic Reynolds number R_m = μ_oσlW where μ_o is the absolute magnetic permittivity, σ is the electric conductivity, l is the wavelength, and W is the velocity of the wave propagation. (authors)

[en] The dispersion characteristics of the circularly polarized electromagnetic waves propagating along a homogeneous magnetic field in a dusty plasma have been investigated theoretically. The Vlasov equation has been employed to find the response of the magnetized plasma particles where the dust grains form a static background of highly charged and massive centers having certain correlation. It is found that in addition to the usual Landau damping which is negligible in the low temperature approximation, a novel mechanism of damping of the Alfven waves due to the dust comes into play. The modification and damping of the Alfven waves depend on the dust perturbation parameters, unequal densities of plasma particles, the average correlation length of the dust grains, temperature of the plasma and the magnetic field. (author)

[en] The q-profile has been determined inside the q=1 surface of ion cyclotron resonance frequency (ICRF) heated plasmas from the observed toroidicity induced Alfven eigenmodes (TAE) that appeared before giant sawtooth crashes. The q-profile deduced from the TAE spectrum is in good agreement with the one obtained from motional Stark effect measurements. (author). Letter-to-the-editor

[en] Space and astrophysical Alfven waves usually excist in a plasma containing thermal and nonthermal particles, and generally the thermal electron and ions have unequal number densities. Nevertheless, the linear properties of the waves are invariably assumed to be determined by a chargeneutral thermal plasma in the absence of the nonthermal particles, while the nonthermal particles cause growth or additional damping superposed onto the background model. Here, both analytic plasma theory and numerical solutions of the dispersion equation, unequal thermal electron and ion number densities (due to the presence of the nonthermal particles) may cause fundamental low wavenumber modifications to the Alfven modes, including the creation of a new resonance and severely modified dispersion. Thes results are found for both cold and warm plasmas. Previous work on Alfven waves should be re-evaluated in view of these results. (author). 6 refs.; 2 figs

[en] Drift-Alfven vortices are investigated, taking into account the nonlinear ion dynamics parallel to the external magnetic field. It is found that the parallel ion motion restricts the vortex speed. (author)