Authors: Valeriy Tenishev (Univeristy of Michigan)

Understanding the radiation environment due to solar energetic particles in the heliosphere and the Earth’s magnetosphere is a challenging and practically important task. Geomagnetic field deflects SEPs moving through geospace though some of these particles propagate to LEO and have a high penetrating capability, thus producing significant radiation hazard for human spaceflight. Exposure to energetic particles often leads to malfunctions and unexpected failures of electronics onboard spacecraft. The most vulnerable are exploratory missions when outside of the Earth’s magnetosphere.

Numerical modeling of the radiation environment due to SEPs in the inner heliosphere and geospace is a multifold problem. That includes simulating 1) dynamics of solar wind and the interplanetary magnetic field, 2) global modeling of the Earth’s magnetosphere, and 3) modeling transport and acceleration of SEPs in the inner heliosphere and geospace.

In the presented work, we combined the results of modeling different parts of SEPs propagation in the inner heliosphere and geospace. First, we solve the Focused Transport equation to simulate the transport and acceleration of SEPs as they propagate in the inner heliosphere. Then, we model the transport of SEPs in geospace using a realistic geomagnetic field. The goal of the task is to characterize the variability of the SEPs population in the inner heliosphere and geospace in a self-consistent way. This presentation discusses the integrated modeling approach employed in this study and summarizes the results.