Long term variations of the amplitude-phase interrelation of the cosmic ray anisotropy first harmonic

Abstract

There are some special directions in the interplanetary space, which are set by the solar wind velocity and position of the interplanetary magnetic field lines. Due to this a strongly inhomogeneous distribution of the phases and amplitude-phase interrelation appear in the first harmonic of the cosmic ray anisotropy. To study the long term variations of cosmic ray anisotropy the characteristics of its first harmonic defined for each hour by global survey method have been used throughout the period 1957-2010. For each year of this period longitudinal distribution of the cosmic ray vector anisotropy and its amplitude-phase relation were obtained. The results clearly demonstrate the dependence of cosmic ray anisotropy variations on the solar activity and solar magnetic cycles. Periods of specific behavior of the anisotropy are extracted and discussed. The results by this study obtained are consistent with the convection-diffusion model of the anisotropy.