Dynamics of fluxes of protons with energies 30–80 keV during geomagnetic storms on January 21–22, 2005, and December 14–15, 2006, according to data from low-orbit satellites

Abstract

We present the results of a comparative analysis of the dynamics of three populations of fluxes of protons with energy 30–80 keV as measured by NOAA solar-synchronous satellites (POES 15, 16, 17) at low latitudes (L < 2) and at latitudes lower and higher than the boundary of isotropic precipitation during the geomagnetic storms on January 21–22, 2005 and December 14–15, 2006. Based on a complex analysis of experimental data on particle fluxes at low orbits and on measurements of solar wind parameters performed by the ACE spacecraft, we have studied the dynamical peculiarities of the fluxes of particles and of their longitudinal distributions depending on the conditions in the interplanetary medium. It is shown that an increase of trapped particle fluxes and the development of the main phase of the geomagnetic storm on January 21–22, 2005 are associated with the magnetosphere’s response to a prolonged action of an extremely powerful coronal mass ejection at a northern orientation of the IMF. On December 14, 2006 an insufficient amplitude and duration of the pressure impulse did not result in development of a disturbance similar to January 21–22, 2005. The development of the main phase of this storm is related to a southward turn of the IMF, which has occurred only seven hours after the SSC.