Open AccessGeneration of electromagnetic perturbations by acoustic waves in the ionosphere
Author(s) -
Aburjania George D.,
Machabeli George Z.
Publication year - 1998
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/97ja03060
Subject(s) - physics , electromagnetic radiation , ionosphere , polarization (electrochemistry) , earth's magnetic field , wavelength , ion acoustic wave , computational physics , geophysics , plasma , wave propagation , magnetic field , optics , chemistry , quantum mechanics
A new mechanism of transformation of long‐wavelength acoustic waves into electromagnetic in partially ionized plasmas is suggested. The range of geomagnetic pulsation frequencies has been studied. It is shown that in collective motion acoustic wave involves the charged particles of media by means of the collisions. Relative motion of charged particles excites the alternating current with arbitrary phase, and consequently, the parametric generation of electromagnetic fields occurs. The growth rates, excitement thresholds, spectra, and polarization of electromagnetic disturbances are determined. The suggested mechanism not only has generalphysical importance, but it can also explain the observed data and the prediction of expected character of atmospheric waveprocesses before the earthquake.