CME Types, Their Interplanetary Manifestations (ICMEs) and Effects on Cosmic Ray Intensity

We have considered CMEs, halo CMEs and partial halo CMEs and their interplanetary signatures (magnetic clouds, ejecta and shocks). Influences of these structures on cosmic ray intensity have been studied. method of superp osed epoch (Chree) analysis has been employed; key days corresp ond to the arrival of these structures. It is observed that halo CMEs are most effective transient modulators as compared to others. Consideration of interplanetary manifestations of these CMEs shows that the effects of magnetic clouds and ejecta itself, on cosmic ray modulation are small and not significantly different in two cases. However, both the shock-ejecta and shock-cloud combinations are much more effective in transient modulation and any difference in their effectiveness apparently does not depend on the structure (ejecta or magnetic cloud) following the shock.