Speaker
Description
Galactic cosmic rays (GCRs) are affected by solar modulation while they propagate throughout the heliosphere. The study of the time variation of the GCR spectrum observed at Earth can shed light on the underlying physical processes, specifically diffusion and particle drifts. The AMS-02 experiment on board the International Space Station measured with very high accuracy the time variation of the cosmic ray proton and helium flux between May 2011 and May 2017 in the rigidity range from 1 to 60 GV. In this work, a comprehensive 3D steady-state numerical model is used to solve the Parker's transport equation and to reproduce the monthly fluxes observed by AMS-02. Preliminary results on the time dependence of the diffusion coefficient for proton and helium will be presented.
