Multi-fractal Analysis of Cosmic Rays over Mid- and High-Latitude Stations During Severe Geomagnetic Storms

Abstract

This study explores the multi-fractal properties of cosmic-ray (CR) counts collected from two mid-latitude neutron-monitor stations, Newark (NEWK) and Irkutsk 3 (IRK3), and two high-latitude stations, Thule (THUL) and Inuvik (INVK), during periods of severe geomagnetic storms. By employing multi-fractal along with time-series analysis, we did an in-depth examination of CR count variations to demonstrate the effectiveness of these methods in analyzing complex signals associated with astrophysical and solar phenomena. The findings reveal that CR count rates across stations at different latitudes exhibit multi-fractal characteristics, reflecting a range of scaling exponents that capture varying degrees of correlation and variability within the system. The results underscore that solar activity, geomagnetic events, and interactions with Earth’s magnetic field play a more crucial role in determining multi-fractality than the geographic location of the measurement station. Moreover, the study shows that geomagnetic events exert a stronger influence on the multi-fractal properties of CR count rate than the geographic location of station, underscoring the impact of solar storms and Earth’s magnetic field on the distribution and intensity of CRs. This work emphasizes the value of multi-fractal analysis as a powerful tool for investigating the complex nature of CR counts and its sensitivity to both extraterrestrial and terrestrial factors.