Operational inner magnetosphere particle transport and acceleration model (IMPTAM) for 1–300 keV electrons

Abstract

Surface charging, the process of charge deposition on covering insulating surfaces of satellites is directly linked to the space environment at a time scale of a few tens of seconds. Accurate specification of the space environment at different orbits is of key importance. We introduce the model operating online in near-real time for low energy (< 200 keV) electrons in the inner magnetosphere, called Inner Magnetosphere Particle Transport and Acceleration model (IMPTAM). This model in its various versions has been operating online since March 2013 (latest version at imptam.engin.umich.edu) and it is driven by the real time solar wind (solar wind number density, dynamic pressure and velocity) and Interplanetary Magnetic Field (IMF), Y and Z components and total magnitude, parameters and by the real time Dst and Kp indices. The model provides the low energy electron (and proton) flux at all Magnetic Local Times (MLTs) and at L-shells from 3 to 10 and at all satellite orbits inside the modeling region, when necessary. IMPTAM output can serve as an input to assess surface charging levels of spacecraft immersed in severe environments and inside radiation belts models as distributions of electron seed population for further acceleration to MeV energies.