A New Scenario of Solar Modulation Model during the Polarity Reversing

Abstract

When entering the heliosphere, galactic cosmic rays (GCRs) will encounter the solar wind plasma, reducing their intensity. This solar modulation effect is strongly affected by the structure of the solar wind and the heliospheric magnetic field (HMF). To address the effect during the solar maximum of cycle 24, we study the solar modulation under a scenario in which the weights for A = ±1 are determined by the structure of HMF, and the traveling time of GCRs simulated by SOLARPROP is taken into account. We then fit the cosmic-ray proton data provided by AMS-02 and Voyager in the energy range 4 MeV–30 GeV, and confirm that the modulation time lag in this model is about 9 months, which is consistent with the previous studies. This model incorporates a more realistic description of the polarity reversing and provides a more reliable estimation of the solar modulation effect during the maximum activity period.