zastosowania elektromagnetyzmu w nowoczesnych ... - PTZE

XVIII Sympozjum PTZE, Zamość 2008
PLASMA WAVES IN IONOSPHERE
Alexander S. Volokitin 1 , Barbara Atamaniuk 2
(1) Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation,
Moscow, Russia
(2) Institute of Fundamental Technological Research, PAS,
Warsaw, Poland
Plasmas of the Earth’s ionosphere and planets is environment which supports the big variety of
electromagnetic and electrostatic waves, which frequencies and lengths change in very wide
range. In such rare medium as ionospheric plasma frequency of particle collisions is small,
what leads to weak attenuation of waves and possibility of their propagation on the large
distance. Thanks to the specified factors the role of waves in processes of particles and energy
transport in ionosphere is very important. Beside this, a possibility to use plasma waves as a
diagnostics agent to study structure and physical processes in ionosphere is invaluable.
Electromagnetic waves, which can go far from their origin, are especially interesting to this
purpose.
In the given report physical properties of waves for the basic types of the oscillations and waves
existing in ionospheric plasma are considered, with description of those regions and processes
in ionosphere in which the given fluctuations play an essential role. Such linear characteristics
of waves as a frequency dispersion, attenuation and generation rates are discussed briefly. For
concrete examples of lower hybrid fluctuations, Alfven waves and other types of waves,
modern theoretical approaches to calculation of a dispersion, attenuation and generation of
waves in the ionospheric plasma, which is far from conditions of thermodynamic equilibrium,
are considered. Also the most important for the considered waves nonlinear processes are
presented at connection with the certain ionospheric conditions. The methods, used in the
analysis of the most essential nonlinear wave processes in the ionosphere, and the
corresponding equations describing nonlinear dynamics of waves are represented.
This research is supported by KBN grant 0TOOA 01429
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