Comparison of fast plasma flows in the plasma sheet between storm time and non-storm time

In this study we compare occurrence distributions of the plasma flow velocity in the plasma sheet at storm time and non-storm time. Plasma measurements made by the Geotail satellite within 31 RE from Earth are used. It is found that fast plasma flows take place more often at storm time than at non-storm time and that the enhancement of the occurrence frequency is more manifest for tailward flows than for earthward flows especially during the storm main phase. This result suggests that the near-Earth reconnection site tends to be closer to Earth during magnetospheric storms.