Abstract
The present study investigates the long-term variation of Cosmic Ray Intensity (CRI) in relation to Sunspot Number (SSN), Interplanetary Magnetic Field (IMF) and Kp Index during the period 2009–2025, covering Solar Cycles 24 and the beginning of Solar Cycle 25. Cosmic rays are energetic charged particles originating from outer space and their intensity near Earth is significantly influenced by solar activity and heliospheric magnetic conditions. The analysis of annual average values of CRI, SSN, IMF and Kp Index was carried out to examine their correlation and mutual dependence.
The results reveal a strong inverse correlation between CRI and SSN (r = –0.90), indicating that cosmic ray intensity decreases with increasing solar activity. Similarly, CRI shows a significant negative correlation with IMF (r = –0.77) and Kp Index (r = –0.61), suggesting that stronger interplanetary magnetic fields and geomagnetic disturbances act as barriers to the penetration of galactic cosmic rays into Earth’s atmosphere.
The study confirms that solar and geomagnetic parameters play an important role in the modulation of cosmic rays. These findings contribute to a better understanding of solar-terrestrial interactions, space weather processes, and the behavior of cosmic ray intensity during different phases of solar cycles.
KEYWORDS
Cosmic Ray Intensity (CRI), Sunspot Number (SSN), Interplanetary Magnetic Field (IMF), Kp Index, Solar Activity, Space Weather.
Puspraj Singh1*, Nand Kumar Patel2, Preetam Singh Gour3
¹Assistnat Professor, Dept. of Physics, Govt. P.G. College Satna-485005, M.P., India
²Assistant Professor, Dept. of Physics, Govt. P.G. College Panna-488001, M.P., India
3School of Life and Basic Sciences, Jaipur National University, Jaipur-302017, Raj., India