A STUDY ON THE B_s EVENTS IN INTERPLANETARY SPACE AND THE ASSOCIATED CMEs IN 2000

According to the observations from WIND spacecraft, the events of southward magnetic field (B_s events) occurred in 2000 are studied. Among these 12 events, there were 11 events associated with the coronal mass ejections (CMEs). Using the data from WIND, SOHO/LASCO, and SOHO/EIT, we identified the associated CMEs, which were all halo type. All of these CMEs were moving outward with fast speeds and caused shocks ahead. The initial sites of these CMEs on the solar disc were in an asymmetrical region. By studing 5 strong B_s events (B_s ≥ 20 nT), it is found that the energy of the associated CMEs was high, or the associated CMEs just directed to the Earth, or there were several CMEs, which caused one same B_s event combinationally. In addition, during the solar maximum, the relationship between the intense disturbances in interplanetary space and the high-speed streams seem to be weak.