Proton Modulation in the Heliosphere for Different Solar Conditions and Prediction for AMS-02

Spectra of Galactic Cosmic Rays (GCRs) measured at the Earth are the combination of several processes: sources production and acceleration, propagation in the interstellar medium and propagation in the heliosphere. Inside the solar cavity the flux of GCRs is reduced due to the solar modulation, the interaction which they have with the interplanetary medium. We realized a 2D stochastic simulation of solar modulation to reproduce CR spectra at the Earth, and evaluated the importance in our results of the Local Interstellar Spectrum (LIS) model and its agreement with data at high energy. We show a good agreement between our model and the data taken by AMS-01 and BESS experiments during periods with different solar activity conditions. Furthermore we made a prediction for the flux which will be measured by AMS-02 experiment.
Comment: Accepted for publication in the Proceedings of the ICATPP Conference on Cosmic Rays for Particle and Astroparticle Physics, Villa Olmo (Como, Italy), 7-8 October, 2010, to be published by World Scientific (Singapore)