Analysis of Cosmic Ray Intensity Variations During Geomagnetic Storms and Interplanetary Disturbances in the Declining Phase of Solar Cycle 24

This study examines the variability of galactic cosmic ray (GCR) intensity during geomagnetic storms and interplanetary disturbances in the declining phase of Solar Cycle 24. It focuses on the relationship between cosmic ray intensity and important solar-terrestrial parameters, including the interplanetary magnetic field (IMF), solar wind speed and plasma conditions, and geomagnetic indices such as Dst and Ap. Ground-based neutron monitor data are used to identify short-term cosmic ray variations, particularly Forbush decreases associated with disturbed solar wind conditions. The study gives special attention to the declining phase of Solar Cycle 24, during which overall solar activity decreased but significant interplanetary disturbances and geomagnetic storms continued to occur. Statistical techniques such as correlation analysis, superposed epoch analysis, and time-lag analysis are used to investigate the response of cosmic ray intensity to changes in solar wind and geomagnetic conditions. The analysis particularly considers the magnitude, timing, and recovery of cosmic ray decreases following interplanetary disturbances. Overall, the study aims to improve understanding of the short-term modulation of cosmic rays by solar and interplanetary disturbances. It also provides insight into the relationship between cosmic ray transport, solar wind conditions, geomagnetic activity, and space-weather variations during the declining phase of Solar Cycle 24