SCIENCE GOAL AND SCIENCE OBJECTIVES: THE MAIN OBJECTIVE OF THIS PROJECT IS TO QUANTIFY UNEQUIVOCALLY THE ROLE PLAYED BY THERMOSPHERIC NEUTRAL WINDS IN DRIVING PLASMA DYNAMICS IN THE EARTH S INNER MAGNETOSPHERE. IN PARTICULAR WE PROPOSE TO ADDRESS THE FOLLOWING SCIENCE QUESTIONS: SQ1: TO WHAT EXTENT DO THERMOSPHERIC WINDS DETERMINE THE ELECTRIC DRIFT SHELL SPLITTING OBSERVED IN THE EARTH S INNER RADIATION BELT? SQ2: TO WHAT EXTENT DO THERMOSPHERIC WINDS MODIFY LOSSES OF ENERGETIC PARTICLES TRAPPED IN THE INNER RADIATION BELT? SQ3: TO WHAT EXTENT DO THERMOSPHERIC WINDS MODIFY THE DRIFT TRAJECTORIES OF THE ENERGETIC PARTICLES INJECTED DURING STORM TIMES? IMPACT: THE RESULTS OF THIS PROJECT WILL INCLUDE THE QUANTIFICATION OF THE FOLLOWING PARAMETERS FOR THE FIRST TIME: (1) THE CORRECTION FACTOR TO APPLY TO THE L* COORDINATE TO ACCOUNT FOR ELECTRIC DRIFT SHELL SPLITTING IN THE INNER BELT TO IMPROVE PHASE SPACE MAPPING (2) THE INNER BELT LOSSES DUE TO NEUTRAL WIND-DRIVEN ELECTRIC FIELDS AND (3) THE IMPACT OF NEUTRAL WINDS ON THE CHARACTERISTICS OF STORM TIME INJECTION TRAJECTORIES. THAT WAY WE PROPOSE TO FURTHER OUR UNDERSTANDING AND SUBSEQUENT PREDICTIVE CAPABILITY OF ENERGETIC PARTICLE DYNAMICS IN THE EARTH S INNER MAGNETOSPHERE (RADIATION BELT AND RING CURRENT) BY UNITING IONOSPHERE THERMOSPHERE AND MAGNETOSPHERE RESEARCH. FURTHERMORE BECAUSE NEUTRAL WINDS ARE KNOWN TO AFFECT MAGNETOSPHERIC DYNAMICS AT OTHER MAGNETIZED PLANETS SUCH AS JUPITER AND SATURN IT IS EXPECTED THAT THE KNOWLEDGE GAINED FROM THE PROPOSED STUDY WILL ALSO HELP US IMPROVE OUR UNDERSTANDING OF ATMOSPHEREMAGNETOSPHERE INTERACTIONS AT OTHER PLANETS. RELEVANCE: THIS STUDY ADDRESSES THE 2ND DECADAL SURVEY GOAL DETERMINE THE DYNAMICS AND COUPLING OF EARTH S MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS . MANY OTHER PLANETS ALSO EXHIBIT AN IONOSPHERE. THUS THE PROPOSED STUDY WILL CHARACTERIZE A FUNDAMENTAL PROCESS WHICH MAY BE IMPORTANT THROUGHOUT THE HELIOSPHERE AND IN OTHER SOLAR SYSTEMS. THIS IS RELEVANT TO THE 4TH DECADAL SURVEY GOAL DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE METHODOLOGY: THE PROPOSED WORK WILL RELY PRIMARILY ON (1) IN-SITU FIELD AND PARTICLE MEASUREMENTS BY THE VAN ALLEN PROBES AND (2) A PHYSICS-BASED COUPLED MODEL OF MAGNETOSPHERE THERMOSPHERE IONOSPHERE AND PLASMASPHERE: THE RCM-CTIPE CODE. THE COUPLED RCM-CTIPE WILL BE USED TO EVALUATE THE CONTRIBUTION FROM THE WIND-GENERATED ELECTRIC FIELDS. IN ORDER TO GUARANTEE FULL CLOSURE FOR THE PROPOSED SCIENCE QUESTIONS WE WILL ALSO CONSIDER OTHER PUBLICLY AVAILABLE DATASETS OF FIELD AND/OR PARTICLE MEASUREMENTS OF GROUND BASED AND SPACE-BASED MEASUREMENTS.