HR: 10:25h
AN: SM52A-01 INVITED     [Abstracts]
TI: Once Upon a Time in the Electron Radiation Belts
AU: * Friedel, R H
EM: rfriedel@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AU: Reeves, G D
EM: reeves@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AU: Koller, J
EM: jkoller@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AU: Chen, Y
EM: cheny@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AU: Zaharia, S G
EM: szaharia@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AU: Jordanova, V K
EM: vania@lanl.gov
AF: Los Alamos National Laboratory, ISR-1: SPACE SCIENCE AND APPLICATIONS MS D466, Los Alamos, NM 87545, United States
AB: The classical concept of a hypothesis tested against experimental data leading to a valid theory remains a challenge when applied to space physics in general and the Earth's dynamic radiation belts in particular. While we have copious ongoing data for the energetic electrons in the trapped radiation environment many processes remain unobservable in principle or depend on parameters not directly measured at all, or not at the same time, or not at the right place. Wave generation from an unstable distribution of particles is a fast process not likely to ever be observable. Observed waves may have local and distributed remote sources. The effects of wave-particle interactions depend both on local densities, composition and wave parameters - AND on their distribution along a given field line. Net radial, pitch angle and energy diffusion effects depend on distributed processes an electron undergoes all along it's drift path. In the radiation belts very few of the processes leading to acceleration, loss or transport of energetic electrons can be observed directly - what we can however measure is their net effect on the distribution of energetic electrons in the radiation belts. The upcoming dual spacecraft RBSP mission, while carefully designed to provide key measurements in the right regions, cannot by itself overcome the endemic limitations listed above. To assess the effect of any mechanism we thus need to employ theory and models - which in turn depend on their own set of assumptions and limitations (like quasi-linear versus non-linear wave partcile interaction theory). By using sophisticated models that combine the effects of all the processes acting on energetic electrons we can develop our understanding of this interplay and test the net output of the models against our data. Success can be declared when our models are capable to reproduce a wide range of radiation belt dynamics - and not only work "once upon a time in the radiation belts". In this talk we outline some of the key data and measurements needed to successfully understand the energetic electron dynamics and present some of the pioneering work done in learning how to combine data and models in a "learning" loop aimed at deciphering the interplay of all the processes acting. We also highlight some of the key missing elements both in the data and modeling that need to be addressed before the launch of the RBSP mission.
DE: 2716 Energetic particles: precipitating
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2753 Numerical modeling
DE: 2774 Radiation belts
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly