Regular Article - Plasma Physics
Correlation analysis of solar energetic particles and secondary cosmic ray flux
Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080, Belgrade, Serbia
Accepted: 5 May 2021
Published online: 8 June 2021
Galactic cosmic rays entering heliosphere are modulated by interplanetary magnetic field which is carried away from the Sun by the solar wind. Cosmic rays are additionally modulated by coronal mass ejections and shock waves, which can produce Forbush decrease, a transient decrease in the observed galactic cosmic ray intensity. Measurements of magnetic field and plasma parameters in near-Earth space detect regularly coronal mass ejections, so it is important to understand the correlation between near-Earth particles fluxes associated with these coronal mass ejections and Forbush decreases. By combining in situ measurements of solar energetic particles with ground-based observations by the Belgrade muon detector, we analysed the dynamics of the variation of galactic cosmic rays. Correlation between variations of the flux of the cosmic rays and average in situ particle fluxes was investigated during Forbush decreases. Correlation exhibited dependence on the energy of solar wind particles, but also on cut-off rigidities of cosmic rays detected on the ground. The goal of cross-correlation analysis is to help in better understanding of how coronal mass ejections affect space weather as well as the effects they have on primary cosmic ray variations as detected by ground-based cosmic ray detectors.
© The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature 2021