LWS TR&T Focus Teams:
Toward combined models of acceleration, loss and transport of energetic electrons and protons in the magnetosphere
Team Chair: Michael Liemohn
Target Description:Radiation belt electrons and protons create a hazardous environment for spacecraft operating in Earth orbit. In recent years we have significantly advanced our understanding of loss, source and transport mechanisms operating in the magnetosphere. A global understanding of the influence of the plasmasphere, plasmaspheric plumes, magnetopause location, ULF and VLF plasmawaves, and ring current particles and electric and magnetic fields is required for prediction of the dynamics of the radiation belts. Two complementary modeling approaches are used in radiation particle studies – Global MHD and particle transport. It is necessary and now possible to combine studies of various magnetospheric processes that populate the ring current, electron and proton radiation belts and to identify the important missing ingredients of both physics and measurements. This includes the critical transition region in the near-Earth (6-12RE) magnetotail. This research is timely for preparation of the Radiation Belt Storm Probes (RBSP) and would leverage the complementary GEM focus group on “Space Radiation Climatology” and “Near-Earth magnetosphere: plasma, fields, and coupling.” As an added note, new observations from the THEMIS spacecraft will be highly relevant to many of the topics described above.
Goals and measures of success: The research objectives include: (1) development of models of the dynamics of the radiation belt electrons and protons and the transition regions; (2) determining how transition region fluxes, ring current particles, plasmasphere, plasmaspheric plumes, electromagnetic waves, and variations of the magnetospheric electric and magnetic fields affect the radiation belt electrons and protons; and (3) an assessment of the importance of the individual constituents and their controlling parameters (inputs) in the overall evolution of the radiation belt system. The measure of success is the improvement of our capabilities to predict the dynamics of radiation belt fluxes.
Types of solicited investigations: Proposals that address this topic should address multiple components of mechanisms by which radiation belt particles are accelerated, lost and transported. The research objectives of proposals include: (1) modeling dynamics of the radiation belt and transition particles (2) determining conditions in the magnetospheric environment under which one or several mechanisms dominate; (3) coupling magnetospheric codes (4) developing models with data-assimilative capabilities or combining models with data (performing reanalysis); and (5) model based sensitivity studies to establish the importance of model input parameters (data / boundary conditions / assumptions).