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41.
Yu. S. Shugay I. S. Veselovsky O. S. Yakovchouk I. N. Myagkova 《Geomagnetism and Aeronomy》2014,54(5):558-567
The relativistic electron flux in the Earth’s outer radiation belt generally decreased by almost three orders of magnitude during the minimum of cycle 23 in 2009. Such a behavior was possibly caused by very low geomagnetic activity during an extremely weak interplanetary field in that period. This decrease was replaced by an increase in the relativistic electron flux by two orders of magnitude during several months after the sunspot minimum at the beginning of 2010. 相似文献
42.
Volume currents in the magnetosheath region are calculated within the framework of a new analytical model. Magnetic field structure in the region is found, satisfying boundary conditions on the bow shock and the magnetopause, and then volume currents are calculated using the Maxwell equation. Surface bow shock and magnetopause currents are calculated, too. Free parameters of the model are interplanetary magnetic field, Mach number of the solar wind flow, distances to the bow shock and to the magnetopause, and field compression at the magnetopause. 相似文献
43.
Solar and Heliospheric Causes of Geomagnetic Perturbations during the Growth Phase of Solar Cycle 23
Bothmer V. Veselovsky I. S. Dmitriev A. V. Zhukov A. N. Cargill P. Romashets E. P. Yakovchouk O. S. 《Solar System Research》2002,36(6):499-506
A database is compiled for the study of solar and heliospheric causes of geomagnetic perturbations with the daily average index A
> 20 that were observed in the period 1997–2000. The number of such events (more than 200) progressively increased and fluctuated as the current solar cycle developed. It is established that geomagnetic storms are generated by dynamical processes and structures near the center of the solar disk in a zone of several tens of degrees, and these processes are responsible for the appearance in the Earth's region, within several tens of hours, of quasistationary and transient solar wind streams with a sufficiently strong southward component of the heliospheric magnetic field. These streams lasted more than a few hours. The following structures can serve as morphological indicators for the prediction of the appearance of such streams: (1) active and disappearing filaments derived from synoptic -maps of the Sun, (2) solar flares, (3) coronal holes and evolving active regions, and (4) the heliospheric current sheet. The geometry of coronal mass ejections needs further observational study. 相似文献