Variations of Cosmic ray intensity in relation to Sunspot Number and Solar Wind Parameters over the period 1996-2019

Abstract

Variation of Solar Wind Parameters (Proton density, Speed of SW and IMF-BZ) are changes with Cosmic ray intensity during solar cycle 23 and 24. In this work, we using the cosmic ray intensity (CRI) variation data from Oulu (Rc = 0.81GV) neutron monitors and solar-interplanetary activity data used from OMNIWeb data center for the analysis. The work includes solar wind speed, interplanetary magnetic field Bz and solar wind proton density selected indices during the period 1996-2019. Variation of solar wind plasma and interplanetary magnetic field coefficients has been studied with CRI. The study of the correlation between Sunspot number and cosmic ray intensity has been analyze and found inversely correlated with coefficient r = - 0.87. It is found that there is a linear negative correlation between Solar wind speed verses the cosmic ray intensity with correlation coefficient -0.53. The interplanetary magnetic field (IMF-Bz) shows a high negative correlation (r = -0.90) with Cosmic ray intensity for the solar cycle 23 and 24. The weak positive correlation coefficient has been found yearly average value of Cosmic ray intensity (CRI) with proton density (r = 0.19) for the study period. The solar wind index shows very remarkable relationship with CRI.