Galactic cosmic ray and recurrent enhancement of solar wind velocity

Long-term variations of the intensity for galactic cosmic rays and low energy ions have been investigated using the solar wind parameters. A distinct long-term decrease of cosmic rays intensity associated with the recurrent corotating interaction regions was observed at 1AU in 1993/94. The recurrent enhancements of solar wind velocity and low energy ion intensity were observed in this period. In particularly, it was found that the peak solar wind velocity have good anti-correlation with the high energy galactic cosmic ray intensity. In this event, recurrent enhancements of solar wind velocity are closely associated with the long-term decrease in the galactic cosmic ray intensities.