Rigidity dependence of the intensity variations of galactic cosmic rays

Abstract

For the investigation of the interactions of galactic cosmic rays with the solar wind plasma and/or interplanetary magnetic field, it is important to know the rigidity dependence of the intensity variations of galactic cosmic rays in detail. In this paper, we have performed a regression analysis between the cosmic ray intensity variations and the relative solar wind velocity and obtained the rigidity dependence of the resultant regression coefficients. We have divided the data into two durations of active and calm by a criteria which is based on the data of neutron monitor of the lowest geomagnetic cut-off rigidity on the Earth.