Magnetic Storms Accompanied with Steady Magnetospheric Convection and Characteristics of the Ring Current during the Storms

Abstract

In this paper,12 magnetic storms accompanied with Steady Magnetospheric Convection (SMC) were selected from 2001 to 2017 based on our new criterion. It was found that these magnetic storms have the same characteristics: a long main phase up to about 10 hours; a minimum platform period for each of their SYM-$H$, which lasts about 3 to 10 hours; when these magnetic storms occur, the partial ring current is located at the dusk-side constantly, and its duration is equal to the stable southward driving time of the $B_z$ component of IMF. In addition, the ion loss time during its platform period was calculated, though there were some differences in the lifetime of the ions in different events, the lifetime of the ions in our events is much longer than models. And there is no obvious relationship between the lifetime of the ions and the length of the platform period. Based on our study, the decay of ring current is slowed down as the the SMC event during the magnetic storm brings more energy.