PROBLEMS OF GEOCOSMOS

Proceedings of the 7th International Conference "Problems of Geocosmos" (St. Petersburg, Russia, 26-30 May 2008)
Fig.5 IRIS spectral analysis for 0.0017Hz, 16.02.2003
This method has been formally applied to calculations for every of IRIS beams and result of analysis is
presented on Fig.5. It is clearly seen that there is an obvious maximum in signal level for expected frequency
of transmitter (0.0017 Hz) right in the 9 th ray.
Conclusions
Different types of data and different methods have been included in analysis and these analyses show that
the effect of heating can be seen in the level of ionosphere and orbits of Cluster. Thus it makes possible
sounding of disturbed zone in the system of coupled ionospheric-magnetospheric interaction. But as to
window fourier and wavelet analysis one can say that there is some effect at expected frequency, but also this
effect exists for other frequencies and it is not so obvious that just heating is responsible for such behavior of
parameters. So the single experiment is not enough for definite statement and other coordinated and
combined experiments including satellite and ground based observations are needed.
As to IRIS data and it’s analysis it seems to be rather optimistic that such a good effect appears in the
expected zone (in 9 th beam). In Gavrasov et al.(2004) it is shown window fourier analysis of the data and it
doesn’t show such a good effect due to very problem with noise filtering. The method applied by Odintsov is
developed especially for very low frequency cases that are more common for geophysical research. And it
seems to prove its value. So this method seems to be useful to try it in other data analysis.
References
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Odintsov V.I., Konradov U.I., Kuksa A.A., Application of Matlab Web Server in geophysics for
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Gavrasov A. Maulini A., Frolov A. Experiments on artificial excitation of ionosphere spent on 16 february
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