SCIENCE GOALS AND OBJECTIVES: CHARGED IONS (E.G. SOLAR WIND AND MAGNETOSPHERIC IONS) UV PHOTONS AND BY METEOROID IMPACT ARE WELL STUDIED PROCESSES AND THOUGHT TO BE THE MAIN SOURCES FOR SPUTTERED SPECIES FROM AIRLESS BODIES. HOWEVER THE CONTRIBUTIONS FROM MAGNETOSPHERIC ELECTRONS ARE TYPICALLY ASSUMED TO BE VERY LOW. PRELIMINARY WORK HAS SHOWN THAT ELECTRONS - PARTICULARLY THOSE IN THE MID-ENERGY (200-1000 EV) RANGE - CAN LEAD TO SIGNIFICANTLY HIGHER LEVELS OF DESORPTION FROM SURFACES THAN PREVIOUSLY REPORTED AND ASSUMED BY MOST MODELS INDICATING THAT THE ACTUAL SPUTTERING YIELDS FROM ENERGETIC ELECTRONS SHOULD BE STUDIED AND INCLUDED AS A POTENTIAL SOURCE. OUR PRELIMINARY WORK FOUND THAT ELECTRON-STIMULATED DESORPTION (ESD) PROCESSES LEADS TO THE DESORPTION OF SEVERAL SPECIES OF CONSIDERABLE INTEREST TO PLANETARY SCIENCE; FOR EXAMPLE WHEN WATER ICE WAS STUDIED BY ESD THE EJECTION OF O+ O++ O2+ H3+ H2O2+ H3O+ AND OH+ WERE READILY OBSERVED. IN ADDITION THE MAJORITY OF THE MASS LEAVING THE ICE WAS FOUND TO BE IN THE FORM OF LARGE CLUSTERS (E.G. (H2O)4-H+) RATHER THAN WATER. HERE WE PROPOSE TO MEASURE THE (RELATIVE AND ABSOLUTE) YIELDS OF ALL POSITIVE NEGATIVE AND NEUTRAL SPECIES DESORBING FROM ICY SURFACES WHEN SUBJECTED TO ENERGETIC ELECTRONS. METHODOLOGY: WE WILL DESIGN AND BUILD A LOW-COST TIME-OF-FLIGHT MASS SPECTROMETER INSTRUMENT CAPABLE OF ANALYZING THE POSITIVE AND NEGATIVE IONS PRODUCED FROM A PULSED ELECTRON SOURCE OVER THE ENERGY RANGE OF 0-2 KEV. OUR LABORATORY IS EQUIPPED WITH A HIDEN HAL 201 RESIDUAL GAS ANALYZER (RGA) FOR THE DETECTION OF NEUTRALS HOWEVER A HIDEN IDP MASS SPECTROMETER WHICH IS 2 ORDERS OF MAGNITUDE MORE SENSITIVE AND SPECIFICALLY DESIGNED FOR THE DETECTION OF IONS AND NEUTRALS WILL BE REQUESTED WHICH CAN ADDITIONALLY DETERMINE THE ENERGY OF THE DESORBED SPECIES. THE ICES WILL ADDITIONALLY BE STUDIED USING A QUARTZ CRYSTAL MICROBALANCE (QCMB) AND FTIR SPECTROSCOPY. A LOW ELECTRON CURRENT WILL BE USED AND ALSO VARIED TO ENSURE THAT SINGLE EVENTS ARE OCCURRING AND THAT ION-MOLECULE REACTIONS FROM SPECIES LEAVING THE SURFACE DO NOT INFLUENCE THE RESULTS. THE INTERPLAY BETWEEN THE SUBSTRATE AND CONDENSED ICES OF VARYING THICKNESSES WILL ALSO BE INVESTIGATED (E.G. USING COPPER ALUMINUM SILICATE). HERE WE WILL LOOK AT: I) PURE ICES THAT REPRESENT THE BULK SPECIES WITHIN ICY SATELLITES ICY RINGS AND TNOS II) MIXED ICES THAT REPRESENT THE BULK SPECIES WITHIN ICY SATELLITES ICY RINGS AND TNOS III) PREVIOUSLY IRRADIATED PURE AND MIXED ICES TO SEE THE DEGREE TO WHICH RADIOLYTIC PRODUCTS CAN BE SPUTTERED. RELEVANCE: THIS WORK FALLS UNDER THE SCOPE OF THE SOLAR SYSTEMS WORKINGS PROGRAM SINCE IT DEALS WITH THE MASS AND ENERGY EXCHANGE BETWEEN ICY SOLAR SYSTEM BODIES AND THE MAGNETOSPHERES OF ICY RINGS AND ICY SATELLITES IN THE SOLAR SYSTEM.