Study of Diurnal Anisotropy Variation in Cosmic Ray Intensity During Minimum Solar Activity Period

Year : 2025 | Volume : 14 | Issue : 02 | Page : 30 37
    By

    Arvind Dubey,

  • Jyoti Dalal,

  1. Professor, Department of Physics, Seva Sadan College, Burhanpur, Madhya Pradesh, India
  2. Professor, Department of Physics, Seva Sadan College, Burhanpur, Madhya Pradesh, India

Abstract

we present a comprehensive study of cosmic ray variations over the period from 1964 to 2018, encompassing solar cycles 20, 21, 22, 23, and 24. Both annual average and day-to-day variations have been analyzed to capture the temporal dynamics of cosmic ray intensity across multiple solar cycles. The study focuses particularly on periods of minimum solar activity, namely the years 1965, 1976, 1986, 1996, and 2008, when cosmic ray modulation is most pronounced and solar influences on galactic cosmic rays are minimal. Using data from multiple neutron monitoring stations worldwide, the amplitude (%) and phase (hours) of cosmic ray intensity at ground level were determined and grouped into equal intervals for detailed statistical analysis. The percentages of occurrence of days corresponding to different amplitude and phase intervals were calculated to evaluate patterns across varying phases of solar activity. This approach provides a systematic method for quantifying both the magnitude and timing of cosmic ray variations, allowing for inter-comparison across different solar minima and monitoring sites. Additionally, the study demonstrates the usefulness of long-term neutron monitor data in capturing subtle temporal trends and establishing empirical relationships between cosmic ray intensity and solar activity parameters. Overall, this work contributes to a deeper understanding of cosmic ray modulation over multiple solar cycles and lays the groundwork for improved predictive modeling of cosmic ray variations in relation to solar and heliospheric processes.

Keywords: Cosmic rays, diurnal variation, solar activity period

[This article belongs to Research & Reviews : Journal of Physics ]

How to cite this article:
Arvind Dubey, Jyoti Dalal. Study of Diurnal Anisotropy Variation in Cosmic Ray Intensity During Minimum Solar Activity Period. Research & Reviews : Journal of Physics. 2025; 14(02):30-37.
How to cite this URL:
Arvind Dubey, Jyoti Dalal. Study of Diurnal Anisotropy Variation in Cosmic Ray Intensity During Minimum Solar Activity Period. Research & Reviews : Journal of Physics. 2025; 14(02):30-37. Available from: https://journals.stmjournals.com/rrjophy/article=2025/view=225002


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Regular Issue Subscription Review Article
Volume 14
Issue 02
Received 20/03/2025
Accepted 15/05/2025
Published 28/08/2025
Publication Time 161 Days
137

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