About Cosmic Ray Modulation in the Heliosphere

Abstract

Cosmic ray fluxes in the heliosphere are modulated by solar wind with an embedded solar interplanetary magnetic field. The solar activity changes with a period of ~11 year, and this is the main reason for the observed 11-year variations of cosmic ray fluxes. Besides this, the directions of magnetic fields in solar polar regions and in the heliosphere change to the opposite direction every ~11-years. This causes, in addition, the presence of another 22-year solar magnetic cycle and contributes features to the known ~11-cycle. In this article, we discuss the generally accepted picture of cosmic ray modulation in the heliosphere and show that it requires several changes.