Physics of auroral phenomena : proceedings of the 35th Annual seminar, Apatity, 28 Februaru – 02 March, 2012 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2012. - 187 с. : ил., табл.

E.S. Gorshkov, V. V. Ivanov In addition, readings of the sensor practically do not correlate with temperature (correlation coefficients between T and dDB and / are 0.08 and -0.08, respectively). The changes in daily average values apparently correspond with such seasonal factors as Polar day-night alternations. Particularly, during a polar night dDB decreases to the minimum, while/ rises to the maximum. Matching polynomial trends (fifth-order polynomials) for dDB and / with the equation of time (ET) and the equation of equinoxes (EE) (see Fig.2) revealed significant correlations of ET and EE variations with / (direct correlation at r = 0.53, r = 0.83) and dDB (inverse correlation at r = -0.25, r = -0.64). The polynomial trends for readings correlated at r = -0.84. At the same time, short-period fluctuations of dDB and / corresponded with sign reversal for the sector structure of the interplanetary magnetic field (IMF) see Fig.3 (data averaged over 9 spots). The correlations between them are 0.52 and -0.46, respectively. Additionally, the changes of readings are indirectly (via affecting IMF) influenced by the Moon orbital position (phase) and its orbital velocity. Fig. 4 represents matching variations of the sign of IMF sector structure (curve 1), the Moon phase (curve 2) and orbital velocity of the Moon (curve 3), the analysis of which shows that the new moon and the maximum of the positive sector during the period of increasing orbital velocity of the Moon (decreasing distance between the Earth and the Moon) contribute to preserving the periodicity of IMF. Without these conditions, IMF periodicity is disturbed. Fig. 2 Comparing long-term fluctuation (fifth-order polynomial) of/ (curve 1) and variations of the equation of time (curve 2) and the equation of equinoxes (curve 3) Fig. 3 Comparing fluctuations of/(averaged over 9 spots, curve 1) and variations of sector sign of IMF (curve 2) 166