Modeling relativistic solar particles in the inner solar system during an extreme event

Abstract

We explore extreme conditions in the inner Solar System's radiation environment by modeling the transport of SEPs out to the orbit of Jupiter during an extreme solar event. We use state-of-the art simulations of SEP radial transport that incorporate a radial dependence of the pitch-angle scattering mean free path based on computational results regarding solar wind turbulence. We input the SEP spectrum, injection profile, and interplanetary transport conditions as deduced for the large relativistic solar proton event of 2005 Jan 20 from an analysis of data taken by the Spaceship Earth network of polar neutron monitors. We calculate the SEP intensity profiles in interplanetary space at the orbits of Mercury, Venus, Earth, Mars, Ceres, and Jupiter. Partially supported by the Thailand Research Fund and NASA's Living With a Star program under grant NNX08AQ18G.