PARTICLE TRANSPORT IN A REALISTIC INTERPLANETARY MAGNETIC FIELD

Abstract:

In the study of solar energetic particle events (SEPs), charged particles are assumed to propagate along Parker field lines from the Sun to 1 AU. However, there are cases of impulsive SEPs where in-situ observations showed a clear deviation from the source region. A possible explanation of such events is that the field lines are non-Parker, and they meander in the interplanetary space. In this work, we examine particle transport in a non-Parker field. In particular, we consider field line's random walk caused by the foot point motion. We generate random δφ and δθ and calculate both Parker and stochastic fields numerically in all space. We follow the particle's motion by solving the Lorentz force directly. We explicitly examine how much deviation the in-situ observation can be from the source region.