Effects of heliospheric boundary structures on galactic cosmic ray transport : Global MHD and large-scale test particle simulations

The statistics of galactic cosmic rays (GCRs) invading the heliosphere are investigated using numerical simulations. First, a time stationary global heliosphere is reproduced using an MHD simulation. Then, motions of a large number of GCR protons with initial Lorentz factor 10 (10 GeV) and 1000 (1 TeV), distributed in the interstellar space around the heliosphere, are numerically solved. We map the positional distribution of the GCRs arriving at 50 AU from the Sun. Our results show that the arrival position of GCRs depends on their energies. We discuss the statistical behavior of the arriving GCRs at each energy.