| Autor: |
G.F. Tulinov, S.I. Avdiushin, A.A. Pokhunkov |
| Rok vydání: |
1987 |
| Předmět: |
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| Zdroj: |
Advances in Space Research. 7:217-221 |
| ISSN: |
0273-1177 |
| DOI: |
10.1016/0273-1177(87)90095-0 |
| Popis: |
δ = (O/N2)exp/(O/N2)mod ratios are analysed for the polar thermosphere depending on the season and the heliogeophysical activity where (O/N2)exp values are measured at high latitudes with radiofrequency mass spectrometers at MP-12 rocket launchings and (O/N2)mod values are calculated for the corresponding conditions of every experiment from 4 models (DTM, MSIS-77, MSIS-83 and Kohnlein model (KL)). The analysis reveals certain regularities in variations for different models. In summer δDTM does not depend on the heliogeophysical activity and is within a factor of 2–3 for the polar cap and the daytime cusp at 150 km; during the polar night δDTM depends on the geomagnetic disturbance and varies with the solar activity cycle. The δMSIS-77 and δKL values have little dependence on the heliogeophysical conditions and have approximately the same seasonal variations. During the polar night δMSIS-83 corresponds to 1 ± 0.25 at high and low solar activity. The increase in δ dispersion for every model considered is noted at low solar activity in the morning and evening sectors of the auroral oval. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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