Stochastic simulation of cosmic ray modulation including a wavy heliospheric current sheet

We present a quasi- steady two- dimensional ( axisymmetric) model of the heliospheric transport of galactic cosmic rays. The model is based on stochastic simulation techniques and includes all the modulation mechanisms that cosmic rays experience in the heliosphere: convection, adiabatic cooling, diffusion, and drifts. A special emphasis is given to the cosmic ray transport in the vicinity of the heliospheric current sheet ( HCS), and a new method to calculate the wavy current sheet drift is presented. We study cosmic ray modulation in different solar modulation conditions and levels of waviness of the current sheet. We discuss changes in the cosmic ray spectrum and the dominant streaming patterns of cosmic rays in the heliosphere for different solar polarities and HCS tilt angles.