SCIENCE GOALS AND OBJECTIVES: THE DEVELOPMENT OF LOW ENERGY (FEW EV TO HUNDREDS OF EV) O+ IONS IN THE INNER MAGNETOSPHERE (KNOWN AS THE O+ TORUS AND FIRST DETECTED BY DYNAMICS EXPLORER 1 IN THE 1980S) IS A CRUCIAL ISSUE FOR VARIOUS ASPECTS OF MAGNETOSPHERIC DYNAMICS SUCH AS THE SOURCE FOR THE RING CURRENT O+ POPULATION AND FIELD LINE RESONANCE RADIAL PROFILES OF ULF WAVES. YET THE IDENTIFICATION OF ITS SOURCES REMAINS A COMPELLING OPEN QUESTION. ALSO IONOSPHERIC O+ OUTFLOW INTO THE MAGNETOSPHERE IS A MANIFESTATION OF FUNDAMENTAL PROCESSES CONCERNING ENERGY AND MASS FLOW WITHIN THE COUPLED INNER MAGNETOSPHERE IONOSPHERE SYSTEM. THE PRIMARY GOAL OF THE PROPOSED PROJECT IS TO SYSTEMATICALLY INVESTIGATE THE OCCURRENCE OF LOW-ENERGY O+ OUTFLOW EVENTS IN THE INNER MAGNETOSPHERE REGULARLY OBSERVED BY THE HOPE INSTRUMENT ABOARD THE TWIN VAN ALLEN PROBES SPACECRAFT (HIGHLY ELLIPTICAL LOW INCLINATION ORBITS WITH APOGEE OF 5.8 RE) THEIR RELATION TO GEOMAGNETIC ACTIVITY AND THEIR EFFECT ON O+ DENSITY ENHANCEMENTS IN THE INNER MAGNETOSPHERE. WE WILL ADDRESS THE FOLLOWING QUESTIONS: SQ1. HOW DOES THE OCCURRENCE ENERGY SPECTRA AND DIRECTIONALITY OF LOW-ENERGY (<KEV) O+ OUTFLOW EVENTS DEPEND ON L MLT AND PLASMAPAUSE LOCATION? SQ2. ARE THESE OUTFLOWS RELATED TO SIGNIFICANT ENHANCEMENTS OF O+ DENSITY IN THE INNER MAGNETOSPHERE? SQ3. HOW DOES THE OCCURRENCE OF O+ OUTFLOW EVENTS DEPEND ON GEOMAGNETIC ACTIVITY? A) HOW IS THE TIMING OF THE OUTFLOW RELATED TO THE VARIABILITY OF SYM-H AND AL INDICES? B) HOW IS THE TIMING OF THE OUTFLOW RELATED TO THE TIMING OF LOCAL DIPOLARIZATION AND/OR FIELD-ALIGNED POYNTING FLUX ENHANCEMENTS? METHODOLOGY: WE WILL USE HOPE DATA FOR THE IDENTIFICATION OF THE LOW ENERGY O+ FIELD ALIGNED ENHANCEMENTS AND MAGNETIC FIELD DATA FROM THE EMFISIS INSTRUMENT FOR THE IDENTIFICATION OF THE PLASMAPAUSE LOCATION (AS INFERRED BY PLASMA WAVE SPECTRA) AND DIPOLARIZATIONS. WE WILL USE EMFISIS MAGNETIC FIELDS TOGETHER WITH ELECTRIC FIELDS FROM THE EFW INSTRUMENT IN ORDER TO CALCULATE THE LOCAL POYNTING FLUX. ALL THE ABOVE INSTRUMENTS ARE ON BOARD THE VAN ALLEN PROBES. WE WILL ALSO USE GROUND GEOMAGNETIC SYM-H AND AL INDICES. GIVEN THE FREQUENT OCCURRENCE OF THE O+ FIELD ALIGNED ENHANCEMENTS AND THE VAN ALLEN PROBES ORBIT PRECESSION AROUND THE EARTH SEVERAL TIMES WE WILL HAVE ENOUGH EVENTS TO CONDUCT A STATISTICAL STUDY. I. WE WILL ADDRESS SQ1 AND SQ2 BY CONSTRUCTING MAPS WITH THE OCCURRENCE OF SUCH EVENTS BINNED WITH L AND MLT IDENTIFYING FOR EACH BIN THE ENERGY RANGE DIRECTIONALITY LOCATION WITH RESPECT TO PLASMAPAUSE LOCATION (WHENEVER THAT IS FEASIBLE) AND THE ASSOCIATED O+ DENSITY ENHANCEMENT. II. WE WILL ADDRESS SQ3 BY CORRELATING SYM-H AND AL INDICES WITH THE OCCURRENCE OF THESE EVENTS AND IDENTIFY ANY DEPENDENCE ON STORM PHASE. WE WILL RELATE THE TIMING OF THESE EVENTS WITH THE TIMING OF LOCAL DIPOLARIZATIONS AND POYNTING FLUX ENHANCEMENTS. FINALLY BY TAKING ADVANTAGE OF THE TWO SPACECRAFT WE WILL INVESTIGATE THE SPATIAL-TEMPORAL VARIABILITY OF THESE EVENTS. RELEVANCE: THIS INVESTIGATION WILL PROVIDE NEW INSIGHTS ON FUNDAMENTAL M-I COUPLING PROCESSES SUCH AS THE IONOSPHERIC O+ OUTFLOW THEREFORE IT DIRECTLY ADDRESSES HIGH-LEVEL SCIENCE GOAL #2 FROM THE HELIOPHYSICS DECADAL SURVEY NAMELY: DETERMINE THE DYNAMICS AND COUPLING OF EARTH S MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS.