High Speed Solar Wind Streams and Cosmic Ray Intensity Variation

Two types of high speed solar wind streams namely flare generated streams (FGS) and corotating streams (CS) are taken to study the short-term changes in cosmic ray intensity. In this work we have selected in two types of streams for the period of 1991 to 1996. It is investigated that both of categories of these solar wind streams are found equally effective in producing cosmic ray intensity decreases. These streams are again group ed in to three classes (smaller, medium and longer) according to their duration of occurrence in days. Further, analysis of this study indicates that the medium solar wind streams are found more effective in producing transient decreases in cosmic ray intensity.