Proton and antiproton modulation in the heliosphere for different solar conditions and AMS-02 measurements prediction

TL;DR

This paper presents a 2D stochastic simulation model for solar modulation of cosmic rays, accurately reproducing observed proton and antiproton spectra and predicting future AMS-02 measurements across different solar conditions.

Contribution

The study introduces a quasi time-dependent 2D stochastic model for solar modulation that accounts for polarity dependence and matches multiple experimental datasets.

Findings

Good agreement with AMS-01, Pamela, BESS, Heat, and Caprice data.

Predicted antiproton/proton ratios for AMS-02.

Model captures polarity-dependent modulation effects.

Abstract

Galactic Cosmic Rays (GCRs) are mainly protons confined in the galactic magnetic field to form an isotropic flux inside the galaxy. Before reaching the Earth orbit they enter the Heliosphere and undergo diffusion, convection, magnetic drift and adiabatic energy loss. The result is a reduction of particles flux at low energy (below 10 GeV), called solar modulation. We realized a quasi time-dependent 2D Stochastic Simulation of Solar Modulation that is able to reproduce CR spectra once known the Local Interstellar Spectrum (LIS). We were able to estimate the different behaviors associated to the polarity dependence of the Heliospheric modulation for particles as well as for antiparticles. We show a good agreement with the antiproton/proton ratio measured by AMS-01, Pamela, BESS, Heat and Caprice and we performed a prediction for the AMS-02 Experiment.