Excitation and propagation of lower-hybrid waves in a bounded, inhomogeneous plasma

Excitation and trapping of lower hybrid waves in striations

The theory of lower hybrid LH waves trapped in striations in warm ionospheric plasma in the three-dimensional case is presented. A specific mechanism of trapping associated with the linear transformation of waves is discussed. It is shown analytically that such trapping can take place in elongated plasma depletions with the frequencies below and above the lower hybrid resonance frequency of the...

Lower-hybrid waves in a plasma with negative ions

The introduction of an electronegative gas (i.e., a gas with a large electron attachment cross section, e.g., SF6) into a plasma has made it possible to study plasmas in which the negative ion density can be much larger than the electron density. lp2 In such a plasma, new phenomena may be expected to occur, in particular, various electrostatic wave modes are modified by the presence of negative...

Resonant Parametric Excitation in Lower-hybrid Heating of Tokamak Plasma*

Radiowave propagation in a statistically inhomogeneous plasma

The present work investigates the propagation of a radio pulse in an unmagnetized, statistically inhomogeneous plasma causing regular refraction and anisotropic scattering. Using the framework of geometrical optics, a Fokker-Planck equation is derived and integrated within a two-moment approximation. The method allows a continuous transition from weak to strong angular scattering and yields pul...

On the Propagation of Calcium Waves in an Inhomogeneous Medium

Although the exact details are disputed, it is well established that propagating waves of increased intracellular free Ca2+ concentration arise from a positive feedback or autocatalytic mechanism whereby Ca2+ stimulates its own release. Most previous modeling of the propagation of Ca2+ waves has assumed that the sites of autocatalytic Ca2+ release, the activation sites, are homogeneously distri...