Variation with electron velocity powers of electron collision frequency and energy transport coefficients in weakly ionised plasmas: Earth's lower ionosphere†

A powerful disturbing wave enters the lower ionosphere and causes a periodic modulation of the electron collision frequency. A simple model is adopted for this disturbed region. The modulation transferred to an obliquely incident wanted wave that is reflected in or near it is investigated. The reflexion coefficient of the wanted wave is found by applying the phase integral method. The complex reflexion height of the wanted wave is a function of time in the modulation cycle. Results are discussed first for an isotropic ionosphere and are then extended to include the effect of the Earth’s magnetic field, and the calculation uses the Booker quartic equation. It is shown that the phase integral method is admirably suited to solve this kind of problem. Some examples are given to illustrate that the greatest amount of modulation is transferred when the wanted wave is reflected near the most disturbed part of the ionosphere. The relation of this to some observed effects near sunrise is discussed.

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Transverse and longitudinal permittivities of a gaseous plasma with an electron collision frequency proportional to the electron velocity

Plasma Physics Reports ◽

10.1134/s1063780x07080107 ◽

2007 ◽

Vol 33 (8) ◽

pp. 696-702 ◽

Cited By ~ 2

Author(s):

A. V. Latyshev ◽

A. A. Yushkanov

Keyword(s):

Collision Frequency ◽

Electron Velocity ◽

Electron Collision ◽

Electron Collision Frequency ◽

Gaseous Plasma

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Effects of temperature and electron collision frequency on the elastic electron–ion collisions in a collisional plasma

Journal of Plasma Physics ◽

10.1017/s0022377813000056 ◽

2013 ◽

Vol 79 (5) ◽

pp. 553-558 ◽

Cited By ~ 2

Author(s):

YOUNG-DAE JUNG ◽

WOO-PYO HONG

Keyword(s):

Phase Shift ◽

Temperature Effect ◽

Cross Section ◽

Collision Frequency ◽

Electron Collision ◽

Elastic Electron ◽

Dynamic Temperature ◽

Electron Collision Frequency ◽

Dynamic Screening ◽

Ion Collision

AbstractThe effects of dynamic temperature and electron–electron collisions on the elastic electron–ion collision are investigated in a collisional plasma. The second-order eikonal analysis and the velocity-dependent screening length are employed to derive the eikonal phase shift and eikonal cross section as functions of collision energy, electron collision frequency, Debye length, impact parameter, and thermal energy. It is interesting to find out that the electron–electron collision effect would be vanished; however, the dynamic temperature effect is included in the first-order approximation. We have found that the dynamic temperature effect strongly enhances the eikonal phase shift as well as the eikonal cross section for electron–ion collision since the dynamic screening increases the effective shielding distance. In addition, the detailed characteristic behavior of the dynamic screening function is also discussed.

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