Simulation study of two major events in the heliosphere during the present sunspot cycle

The two major disturbances in the heliosphere during the present sunspot cycle, the event of June-August 1982 and the event of April-June 1978, are simulated by the method developed by Hakamada and Akasofu (1982). Specifically, we attempt to simulate effect of six major flares from three active regions in June-July 1982 and April-May 1978, respectively. A comparison of the results with the solar wind observations at Pioneer 12 (approx.0.8 AU), ISEE 3 (approx.1 AU), Pioneer 11 (approx.7-13 AU), and Pioneer 10 (approx.16-28 AU) suggests that some major flares occurred behind the disk of the sun during the two periods. Our method provides qualitatively some information as to how such a series of intense solar flares can greatly disturb both the inner and outer heliospheres. A long lasting effect on cosmic rays is discussed in conjunction with the disturbed heliosphere