Программа и тезисы докладов - Институт космических ...

elecTroMagneTic ulF-elF band diSTurbance exciTaTion
in The upper ionoSphere by The ThunderSTorM acTiviTy
V. A. Pilipenko
Space Research Institute of Russian Academy of Sciences (IKI RAN), Moscow, Russia
Various aspects of thunderstorm electric discharge effect on the near-Earth
space are examined. Theoretical estimation of thunderstorm excitement of MHD
structures in Hz band in Alfven resonator and magnetosonic waveguide in the upper
ionosphere are provided. The numerical simulation results of Schumann resonance
‘leakage’ onto the ionosphere altitudes. The study of the mechanisms of impulse
connection between the atmosphere and the magnetosphere in ULF-ELF band by
micro-satellites, low-altitude spacecraft and surface registration systems of lightning
discharges is discussed.
daTa recorded by deMeTer during inTenSe ThunderSTorMS
M. Parrot
LPC2E/CNRS, Orléans, France
DEMETER was a 3-axis stabilized Earth-pointing spacecraft launched on
June 29, 2004 into a low altitude (~710 km) polar and circular orbit that was subsequently
lowered to 650 km till the end of the mission in December 2010. The orbit
was nearly sun-synchronous with an ascending node at ~22.30 LT in the night
sector and a descending node at ~10.30 LT during day-time. DEMETER measured
electromagnetic waves all around the Earth except in the auroral zones (invariant
latitude >65°), then the data files are organized by half-orbit. The frequency range
for the electric field was from DC up to 3.5 MHz, and for the magnetic field from
a few Hz up to 20 kHz. At its altitude, the phenomena observed on the E-field and
B-field spectrograms recorded during night time by the satellite are mainly dominated
by whistlers. But whistlers are also observed during day time when the satellite
is right above the thunderstorms. On one hand, we have searched for the more
intense whistlers which must correspond to the more powerful lightning strokes
occurring below DEMETER. These intense lightning strokes are generally associated
with TLEs (Transient Luminous Events). Maps are shown. On the other hand,
a search has been done to check if this intense lightning activity is able to perturb
the electron and ion densities at the satellite altitude.
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