Influence of Interacting Solar Wind Disturbances on the Variations in Galactic Cosmic Rays.

Analysis of the variation in galactic cosmic rays and changes in various characteristics of Forbush effects associated with the influence of interacting solar wind disturbances on the Earth (disturbances with a time interval between registration of less than 50 h) is presented based on the database of Forbush effects and interplanetary disturbances developed at the Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation. Cases of the pair interaction of high-speed streams from coronal holes and coronal mass ejections in 1995–2019 are considered, and the behavior of the solar wind parameters, the interplanetary magnetic field, and the cosmic ray variations for two types of interacting solar wind disturbances (the interaction of successive coronal mass ejections and the interaction of a coronal mass ejection with a high-speed coronal hole stream) are analyzed. It is found that the average times of the onset of the Forbush effect minimum and the record of the maximum solar wind velocity and the absolute value of the interplanetary magnetic field decrease for the first of a pair of interacting events, i.e., the second events of the pair do not allow the first to develop fully. It is also found that the presence of interaction enriches the second event at the expense of the resources of the first. This increases its geomagnetic efficiency and the degree of cosmic ray modulation in comparison with isolated events. [ABSTRACT FROM AUTHOR]