Excitation of the ionospheric resonance cavity by neutral winds at middle latitudes

Abstract. A new mechanism for the ionospheric Alfven resonator (IAR) excitation at middle latitudes is considered. It is shown that the ionosphere wind system in this region is capable of sustaining the generation of geomagnetic perturbations that can be detected by ground magnetometers. The general IAR dispersion relation describing the linear coupling of the shear Alfven and fast magnetosonic/compressional modes is obtained. The dependence of the IAR eigenfrequencies and damping rates on the perpendicular wave number and on the ground conductivity during the day- and nighttime conditions is analyzed both analytically and numerically. In order to demonstrate the IAR excitation by neutral winds the power spectra of the geomagnetic perturbation on the ground surface are calculated. Furthermore, it is found that Kolmogorov spectra of the ionospheric turbulent neutral winds and the IAR eigenfrequencies lie in the same frequency range that make it possible to enhance the IAR excitation. The relevance of the developed theoretical model to the ground-based observations is stressed.

[1]  R. Sagdeev,et al.  Parametric interaction of kinetic Alfvén waves with convective cells , 2004 .

[2]  R. Sagdeev,et al.  Generation of convective cells by kinetic Alfvén waves in the upper ionosphere , 2004 .

[3]  A. Streltsov,et al.  Numerical modeling of localized electromagnetic waves in the nightside subauroral zone , 2003 .

[4]  W. J. Burke,et al.  Electromagnetic wave structures within subauroral polarization streams , 2003 .

[5]  R. Sagdeev,et al.  Nonlinear dynamics of inertial Alfvén waves in the upper ionosphere : Parametric generation of electrostatic convective cells , 2003 .

[6]  R. Ergun,et al.  Properties of small‐scale Alfvén waves and accelerated electrons from FAST , 2003 .

[7]  R. Ergun,et al.  Electron acceleration in the ionospheric Alfven resonator , 2002 .

[8]  Vassilis Angelopoulos,et al.  Spectral properties of the ionospheric Alfvén resonator observed at a low-latitude station (L = 1.3) , 2002 .

[9]  R. Lysak,et al.  Energetics of the ionospheric feedback interaction , 2002 .

[10]  M. Parrot,et al.  Ionospheric Alfvén resonator revisited: Feedback instability , 2001 .

[11]  A. G. Demekhov,et al.  Pc 1 waves and ionospheric Alfvén resonator: Generation or filtration? , 2000 .

[12]  A. Streltsov,et al.  Dispersive ionospheric Alfvén resonator , 2000 .

[13]  M. Grzesiak.  Ionospheric Alfvén resonator as seen by Freja satellite , 2000 .

[14]  R. Ergun,et al.  FAST Observations of Inertial Alfven Waves in the Dayside Aurora , 1999 .

[15]  J. Kangas,et al.  First evidence at high latitudes for the ionospheric Alfvén resonator , 1999 .

[16]  O. Pokhotelov,et al.  Morphology and physics of short-period magnetic pulsations , 1998 .

[17]  P. Stubbe,et al.  Excitation of the ionospheric Alfven resonator by strong lightning discharges , 1997 .

[18]  A. Fraser-Smith.  ULF magnetic fields generated by electrical storms and their significance to geomagnetic pulsation generation , 1993 .

[19]  V. Trakhtengerts,et al.  Turbulent Alfven boundary layer in the polar ionosphere: 1. Excitation conditions and energetics , 1991 .

[20]  Robert L. Lysak,et al.  Feedback instability of the ionospheric resonant cavity , 1991 .

[21]  S. V. Polyakov,et al.  The ionospheric Alfv/'en resonator , 1990 .

[22]  S. V. Poliakov,et al.  The ionospheric Alfven resonator , 1981 .

[23]  Eh. S. Kazimirovskij,et al.  The earth's ionosphere. , 1981 .

[24]  C. Greifinger,et al.  Theory of hydromagnetic propagation in the ionospheric waveguide , 1968 .

[25]  Charles F. Kennel,et al.  LIMIT ON STABLY TRAPPED PARTICLE FLUXES , 1966 .

[26]  A. Andronov,et al.  KINETIC INSTABILITY OF THE EARTH'S OUTER RADIATION BELT , 1964 .