SCIENCE GOALS AND OBJECTIVES: THE HISTORIC CASSINI MISSION HAS RESOLVED MANY EXISTING MYSTERIES BUT ALSO RAISED MANY NEW QUESTIONS ABOUT THE SATURNIAN ENVIRONMENT. FOR INSTANCE ENCELADUS PLUME GENERATION MECHANISMS AND THE APPARENT LACK OF TITAN ATMOSPHERIC LOSS ARE TWO EXISTING MYSTERIES. THE PRESENCE OR ABSENCE OF MINOR SPECIES CAN PROVIDE ESSENTIAL INPUT TO SOLVING SUCH MYSTERIES. CARBON IN PARTICULAR IS AN EXTREMELY SIGNIFICANT TRACE SPECIES AS ITS RELATIVE ABUNDANCE PROVIDES UNIQUE INSIGHT INTO HOW MUCH OF TITAN S ATMOSPHERE IS ESCAPING AS WELL AS WHAT IS THE SUBSURFACE COMPOSITION OF ENCELADUS. ADDITIONALLY CONFIRMATION OF CARBON ORIGINATING FROM OTHER SOURCES SUCH AS SATURN S ATMOSPHERE THE MAIN RINGS THE OTHER ICY SATELLITES OR A CURRENTLY UNIDENTIFIED POSSIBLE SOURCE HAS EXTREMELY LARGE IMPLICATIONS FOR UNDERSTANDING SATURN S MAGNETOSPHERE AND ITS SOURCES. THUS A BETTER UNDERSTANDING OF THE SPATIAL AND TEMPORAL DISTRIBUTION OF CARBON PARTICLES WILL HELP US BETTER UNDERSTAND BOTH ENCELADUS AND TITAN (ESSENTIALLY A PROBE OF THESE MOONS). UNFORTUNATELY THE MAGNETOSPHERIC CARBON DISTRIBUTION IS NOT WELL UNDERSTOOD BECAUSE THEIR RELATIVE ABUNDANCE IS SMALL COMPARED TO THE DOMINANT WATER GROUP PARTICLE POPULATION MAKING IDENTIFICATION VERY DIFFICULT. HOWEVER WE HAVE RECENTLY DISCOVERED THAT THE RELATIVE AMOUNT OF HIGH ENERGY CARBON IONS IN SATURN S MAGNETOSPHERE IS NOT CONSTANT. ADDITIONALLY THROUGH PREVIOUSLY FUNDED RESEARCH WE WERE ABLE TO LINK HIGH ENERGY PARTICLE COMPOSITIONS WITH LOWER ENERGY CORE ION POPULATIONS. THESE NEW RESULTS COMBINED WITH RECENTLY IMPROVED ION COMPOSITION ANALYSIS TECHNIQUES NOW ESTABLISH THE CAPABILITY TO FULLY CHARACTERIZE THE SPATIAL AND TEMPORAL MAGNETOSPHERIC CARBON DISTRIBUTION. THUS OUR PRIMARY SCIENCE GOAL IS TO CHARACTERIZE MAGNETOSPHERIC CARBON DISTRIBUTIONS FOR EXAMINING ENCELADUS PLUME COMPOSITION AND ACTIVITY CHARACTERIZING TITAN ATMOSPHERIC LOSS ACTIVITY AS WELL AS IDENTIFYING ANY OTHER POSSIBLE SOURCES OF THIS CARBON. IN ORDER TO ACCOMPLISH THESE SCIENTIFIC GOALS WE WILL PURSUE THE FOLLOWING OBJECTIVES: 1) FULLY SPATIALLY AND TEMPORALLY CHARACTERIZE MAGNETOSPHERIC CARBON ION DISTRIBUTION 2) SEARCH FOR THE PRESENCE (OR UPPER LIMITS) OF OTHER RELEVANT MINOR ION SPECIES 3) CONFIRM/DENY POSSIBLE CARBON ION SOURCES FOR MAGNETOSPHERIC C+ ENHANCEMENTS METHODOLOGY: WE PROPOSE TO ACCOMPLISH THESE SCIENTIFIC OBJECTIVES THROUGH A DETAILED ANALYSIS OF ALL AVAILABLE MIMI CHEMS ION COMPOSITIONAL DATA AS WELL AS CAPS ION COMPOSITION DATA FOR THE PRESENCE OF CARBON IONS. THE RESULT WILL BE A FULL CHARACTERIZATION OF MAGNETOSPHERIC ION DISTRIBUTION WITH RESPECT TO TIME AND SPACE. WE INTEND TO ANALYZE THESE DISTRIBUTIONS WITH RESPECT TO ENCELADUS AND TITAN (CONSTRAINED BY INMS OBSERVATIONS) LOCATIONS TO IDENTIFY ANY CORRELATION WITH ONE AND OR BOTH OF THESE SOURCES. WE WILL ALSO EXAMINE OTHER POSSIBLE SOURCES AS WELL AS ATTEMPT TO IDENTIFY ADDITIONAL MINOR ION SPECIES. FINALLY WE WILL INCORPORATE THESE FINDINGS INTO OUR 3-D SATURN MAGNETOSPHERIC PARTICLE MODEL (UPGRADED WITH CARBON INTERACTIONS) TO DETERMINE CONFIRM (OR DENY) AND CONSTRAIN THE SOURCE(S) THAT IS(ARE) CAUSING THE OBSERVED GLOBAL CARBON ENHANCEMENTS. THESE RESULTS WILL ALLOW US TO DETERMINE HOW MUCH OF THE OBSERVED CARBON IS PRODUCED BY TITAN AND HOW MUCH IS PRODUCED BY ENCELADUS AS WELL AS ANY OTHER POSSIBLE SOURCES. WE WILL ALSO IDENTIFY VARIATIONS IN THESE SOURCES. THE RESULTS OF THE PROPOSED RESEARCH WILL PROVIDE NEW CONSTRAINTS FOR CARBON SOURCES IN SATURN S MAGNETOSPHERE WHICH SHOULD CLEAR UP SOME LONG-STANDING QUESTIONS ABOUT CARBON-SPECIES ABUNDANCES IN THESE SOURCES. THUS THIS RESEARCH EXPECTED TO BE HIGHLY SIGNIFICANT.
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