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Dust acoustic mode manifestations in the dusty ionosphere are studied. The reason for an appearance of the low-frequency radio noises associated with such meteor fluxes as Perseids, Orionids, Leonids, and Gemenids is determined. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We investigate limiting values of charges of microparticles for two possibilities of complex (dusty) plasmas in the presence of electromagnetic radiation. The first possibility assumes solid dust grains contained in the plasma while the second one implies the liquid droplets. We obtain analytical expression describing dust particle charging as a result of intensive photoelectric effect. We show that the electrostatic pressure on the surface of charged solid dust particles can affect the strength characteristics of these particles. We obtain the limiting values of the charges of solid dusts, the dusts exceeding this charge value are subjected to total or partial destruction. Necessary conditions and parameters for X-ray sources of electromagnetic radiation are defined to reach these limiting values of dust charges. [ABSTRACT FROM AUTHOR]

Effects associated with neutral component of complex (dusty) ionospheric plasmas which affect dust particle charging are studied. Microscopic ion currents on dust particles with taking into account ion-neutral interaction are presented. Calculations are performed both for the case of negative charges of dust particles, when the influence of Solar radiation on dust particle charging processes is negligible, and for the case of positive charges which is realized in the presence of sufficiently intensive UV or X-ray radiation. We also carry out investigation of the electron heating due to the photoelectric effect. We show that the efficiency of electron heating depends on the density of neutral component of the plasma. As result, we determine altitudes where the influence of the neutral plasma component on dust particle charging processes as well as the electron heating effect are significant and should be taken into account under consideration of the ionospheric complex plasmas. In particular, we show that the effects considered could be important for the description of noctilucent clouds, polar mesosphere summer echoes, and some other physical phenomena associated with dust particles in the ionosphere. [ABSTRACT FROM AUTHOR]

It is shown that, during Perseid, Geminid, Orionid, and Leonid meteor showers, the excitation of low-frequency dust acoustic perturbations by modulational instability in the Earth's ionosphere can lead to the generation of infrasonic waves. The processes accompanying the propagation of these waves in Earth's troposphere are considered, and the possibility of observing the waves from the Earth's surface is discussed, as well as the possible onset of acoustic gravitational vortex structures in the region of dust acoustic perturbations. The generation of such structures during Perseid, Geminid, Orionid, and Leonid meteor showers can show up as an increase in the intensity of green nightglow by an amount on the order of 10% and can be attributed to the formation of nonlinear (vortex) structures at altitudes of 110-120 km. Thus the modulational excitation of the dust acoustic perturbations in the ionosphere has tropospherical response: it influences physical processes and observations in Earth's troposphere. [ABSTRACT FROM AUTHOR]