HIGH-SPEED SOLAR-WIND STREAMS OF 2 DIFFERENT ORIGINS AND COSMIC-RAY VARIATIONS DURING 1980-1986

There are two types of high-speed solar wind streams classified in two categories: coronal-hole and solar-flare-generate streams. These two types are classified in two categories considering the bulk speed, pro ton density, temperature and magnetic field in the interplanetary medi um. Their effects on cosmic ray intensity have been studied on a short -term basis during 1980-1986. Daily means of one middle and one low-la titude set of neutron monitor data have been taken for analysis using the Chree method of superposed epochs. The investigation indicates tha t the solar-flare-generate high-speed solar wind streams are more effe ctive in producing cosmic ray decreases than are the coronal-hole gene rated streams.