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11.
G. A. Zhbankov A. T. Karpachev V. A. Telegin K. G. Tsybulya 《Geomagnetism and Aeronomy》2010,50(1):119-126
It has been indicated how a complex ionogram of topside sounding near the outer slope of the winter southern crest of the
equatorial anomaly, where a large NmF2, gradient and a deep hmF2, minimum are observed, is formed. The model latitudinal cross-sectio n of the ionosphere, used to perform trajectory calculations,
has been constructed based on the corrected Intercosmos-19 data. The ray trajectories have been modeled using the method of
characteristics. It has been indicated that a complex Intercosmos-19 ionogram is formed by an oblique reflection from the
equatorial anomaly crest slope (the main trace) and by a strongly oblique reflection from the crest bottom as a result of
the wave capture by a large-scale inhomogeneity (the additional trace). 相似文献
12.
Unusual complex ionograms obtained by the Intercosmos-19 satellite are considered, in which four diffuse clouds with a characteristic shape are strung like pearls on the main path of the reflected signal. Ray tracing has been used to show that they are associated with 26 layers of irregularities located at altitudes from hmFs2 up to ~900 km. The sizes of the irregularities range from a few kilometers to 100 kilometers, and the intensity of δNe reaches 100%. The heights of irregular layers increase towards the equator, together with a rise of the F2 layer, and are not associated with magnetic field lines. Complex ionograms have been observed on the outer slope and at the top of the crest of the equatorial anomaly. They are probably caused by the processes occurring in the equatorial ionosphere. 相似文献
13.
Romanova N. Yu. Telegin V. A. Panchenko V. A. Zhbankov G. A. 《Geomagnetism and Aeronomy》2022,62(1-2):71-85
Geomagnetism and Aeronomy - The characteristics of irregular ionospheric structures are studied with two different methods in the course of two independent, long-term experiments. The parameters of... 相似文献
14.
Obzhirov A. I. Polonik N. S. Ponomareva A. L. Vereshchagina O. V. Telegin Yu. A. Syrbu N. S. Flint M. V. 《Oceanology》2021,61(6):881-891
Oceanology - Estimates of the content of dissolved methane, hydrogen, and helium in seawater of the Kara Sea were obtained. It was found that the methane concentration in the studied areas varied... 相似文献
15.
Additional strongly remote (up to 2000 km) radio-signal reflection traces on Intercosmos-19 ionograms obtained in the equatorial ionosphere have been considered. These traces, as a rule, begin at frequencies slightly lower than the main trace cutoff frequencies, which indicates that an irregularity with a decreased plasma density exists here. The waveguide stretched along the magnetic-field line is such an inhomogeneity in the equatorial ionosphere. The ray tracing confirm that radio waves propagate in a waveguide and make it possible to determine the typical waveguide parameters: ?δN e ≥ 10%, with a diameter of 15–20 km. Since the waveguide walls are smooth, an additional trace is always recorded distinctly even in the case in which main traces were completely eroded by strong diffusivity. Only one additional trace (of the radio signal X mode) is usually observed one more multiple trace is rarely recorded. Waveguides can be observed at all altitudes of the equatorial ionosphere at geomagnetic latitudes of ±40°. The formation of waveguides is usually related to the formation of different-scale irregularities in the nighttime equatorial ionosphere, which result in the appearance of other additional traces and spread F. 相似文献
16.
The expression for the increment of instability and decrement of diffusion damping of gradient drift waves for ionospheric
altitudes above the F
2 layer maximum is obtained. The gradient drift instability is used to interpret the observations of spread F in the region of large-scale horizontal irregularities of the electron density. Two types of such irregularities observed
on board the Intercosmos-19 (IC-19) satellite in the region of low latitudes (a peak of the density in the dusk ionosphere
and a trough of the density in the dawn ionosphere) are considered. It is shown that the observed gradients of the density
and electric field values in the dawn and dusk ionospheric sectors are quite sufficient for the instability development criterion
to be satisfied in both considered cases. 相似文献