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The Low Energy ElectroStatic Analyzer (LEESA) will measure electrons and protons from 100 eV to 50 keV onboard the DSX spacecraft. This sensor uses hemispherical sector ESAs to achieve a single, 50 degree pitch angle bin. LEESA is a new instrument, based on heritage designs of sensors, analog electronics, and power supply electronics. During the first year of the program, we have carried out a requirements analysis, a concept design phase with trade study, and the preliminary design phase. The results of these are presented., The original document contains color images.

This report contains the summary of the scientific and engineering work performed during the most recent year as part of the development of the High Energy Proton instrument (HEP) and of the Low Energy Particle and Dosimetry instrument (LEPDOS). These instruments are part of the SOBEDS suite of instruments being developed by Amptek, Inc. The purpose of the HEP instrument is to measure the energy spectrum of energetic protons, specifically to obtain a differential spectrum for 25 < E < 440 MeV and integral counts for E > 440 MeV. The purpose of the LEPDOS instrument is to measure: 1) the lower energy protons and electrons that may cause spacecraft anomalies, specifically protons from 0.7 to 80 MeV and electrons from 5 to > 250 keV, 2) the dose and dose rate experienced by spacecraft electronics, 3) particles causing single event effects, and 4) to provide real-time warnings to spacecraft and operators of environmental conditions likely to cause anomalies, such as surface charging and deep dielectric charging. During the most recent year, the seventh year of the contract effort, no spacecraft were selected for the remaining instruments. Since the bulk of the remaining effort is spacecraft specific, very little work was carried out on this contract.

This report contains the summary of the scientific and engineering work performed during the most recent year as part of the development of the High Energy Proton instrument (HEP) and of the Low Energy Particle and Dosimetry instrument (LEPDOS). These instruments are part of the SOBEDS suite of instruments being developed by Amptek, Inc. The purpose of the HEP instrument is to measure the energy spectrum of energetic protons, specifically to obtain a differential spectrum for 25 < E <440 MeV and integral counts for E>44O MeV. The purpose of the LEPDOS instrument is to measure: 1) the lower energy protons and electrons that may cause spacecraft anomalies, specifically protons from 0.7 to 80 MeV and electrons from 5 to >250 keV, 2) the dose and dose rate experienced by spacecraft electronics, 3) particles causing single event effects, and 4) to provide real-time warnings to spacecraft and operators of environmental conditions likely to cause anomalies, such as surface charging and deep dielectric charging.

This document is the Final Report for the Compact Environmental Anomaly Sensor (CEASE) Flight Support Program carried out by Amptek, Inc. under Air Force contract F19628-96-C-0063. The goal of this program was to support the flight code development, functional testing, environmental testing, calibration spacecraft integration, and initial on-orbit checkout of the CEASE S/N 001 and S/N 002 instruments These instruments were built by Amptek, Inc. under the Air Force contract F19628-90-C-0159. The basic instrument descriptions can be found in the final report for the previous contact. Under the current contract, Amptek Inc, supported the successful spacecraft specific design work, final calibration, and the delivery, integration, and launch of two CEASE instruments - S/N 001 onto the Space Test Research Vehicle 1c (STRV-1c) spacecraft and S/N 002 onto the Tri-Service Experiments (TSX-5) spacecraft. This report documents the work conducted by Amptek on these CEASE flight units and an accompanying engineering unit, under the current contract.

This report contains the summary of the scientific and engineering work performed as part of the development of the High Energy Proton instrument (HEP) and of the Low Energy Particle and Dosimetry instrument (LEPDOS). These instruments are part of the SOBEDS suite of instruments being developed by Amptek, Inc. The purpose of the HEP instrument is to measure the energy spectrum of energetic protons, specifically to obtain a differential spectrum for 25 < E < 440 MeV and integral counts for E > 440 MeV. The purpose of the LEPDOS instrument is to measure: (1) the lower energy protons and electrons which may cause spacecraft anomalies, specifically protons from 0.7 to 80 MeV and electrons from 5 to > 250 keV, (2) the dose and dose rate experienced by spacecraft electronics, (3) particles causing single event effects, and (4) to provide real-time warnings to spacecraft and operators of environmental conditions likely to cause anomalies, such as surface charging and deep dielectric charging.

The outer space environment experienced by modern, electronically sophisticated spacecraft can be very hostile due to interactions between complex, sensitive electronics systems and the naturally occurring energetic particle population indigenous to the solar system. The Compact Environmental Anomaly System (CEASE) has been developed as a small, low-power device to monitor space "weather" and to provide autonomous warnings of conditions that may cause operational anomalies in the host spacecraft. CEASE uses a two-element, solid-state telescope and two radiation dosimeters to sample critical energetic particle fluxes and uses a sophisiticated real-time processing program that can forecast hazardous conditions before they affect the spacecraft. The spacecraft, in turn, can re-prioritize its operations, inhibit any anomaly sensitive operations such as attitude adjustments, or initiate other prudent actions as indicated by the CEASE warning flags

The Small On-Board Environmental Diagnostic Sensors Package (SO BEDS) is a suite of spacecraft instruments designed to measure ionizing radiation in the near-Earth space environment. The purpose of data gathered by the SOBEDS instrument is to improve the understanding of the Earth's radiation belts and the effect of ionizing radiation on Air Force space systems. Amptek, Inc. is building three of the SOBEDS instruments: HEP, LEP and DOS. The HEP instrument will measure the differential energy spectrum of protons with energies between 15 and 300 MeV, LEP will measure the differential energy spectra of electrons (0.1

The outer space environment experienced by a modern, electronically sophisticated spacecraft can be very hostile due to interactions between its complex, sensitive electronics systems and the naturally occurring energetic particle population indigenous to the solar system. The Compact Environmental Anomaly System (CEASE) has been developed as a small, low-power device to monitor space 'weather' and to provide autonomous warnings of conditions that may cause operational anomalies in the host spacecraft. CEASE uses a two-element, solid-state telescope and two radiation dosimeters to sample critical energetic particle fluxes and uses a sophisticated real-time processing program that can forecast hazardous conditions before they affect the spacecraft. The spacecraft, in turn, can re-prioritize its operations, inhibit any anomaly sensitive operations such as attitude adjustments, or take any other prudent actions suggested by the potential for dangerous conditions.

The outer space environment experienced by a modern, electronically sophisticated spacecraft can be very hostile due to interactions between its complex, sensitive electronics systems and the naturally occurring energetic particle population indigenous to the solar system. The Compact Environmental Anomaly Sensor (CEASE) is being developed as a small, low-power device to monitor space 'weather' and provide autonomous warnings of conditions that may cause operational anomalies in a host spacecraft. CEASE uses a two-element solid-state telescope, two radiation dosimeters and one SEU detector to sample critical energetic particle fluxes. It uses a sophisticated real-time processing program that can forecast hazardous environmental conditions before they effect the spacecraft The spacecraft, in turn, can re-prioritize its operations, inhibit any anomaly sensitive operations such as attitude adjustments, or take any other prudent action suggested by the potential of erratic conditions.

The effort expended on Task 1 (the Photovoltaic Array Space Power Plus Diagnostics PASP Plus experiment) during the report period, went into on-orbit support for the mission. Amptek, Inc. was called upon to assist in understanding some anomalous behavior in an instrument's performance. On Task 2, the Charging Hazards and Wake Studies (CHAW S) program, the Digital Ion Drift Meter (DIDM) instrument design and build process got underway. Company personnel also supported PL/GPSG at several meetings which were held to discuss spacecraft systems and/or instrument design issues. In addition, the preparation of SPREE hardware for the upcoming re-flight continued. This effort is now almost at an end. Under Task 3, (the Space Wave Interactions with Plasma as Experiment (SWIPE) the hardware was subjected to flight environmental tests, which was successfully concluded, and then delivered to PL/GPSG. System integration testing at the payload integrator's facility was supported by company personnel.

The outer space environment experienced by a modern, electronically sophisticated spacecraft can be very hostile due to interactions between its complex, sensitive electronics systems and the naturally occurring energetic particle population indigenous to the solar system. The Compact Environmental Anomaly Sensor (CEASE) is being developed as a small, low-power device to monitor space "weather" and provide autonomous warnings of conditions that may cause operational anomalies in a host spacecraft. CEASE uses a two-element solid-state telescope and two radiation dosimeters to sample critical energetic particle fluxes and uses a sophisticated real-time processing program that can forecast hazardous environmental conditions before they effect the spacecraft. The spacecraft, in turn, can re-prioritize its operations, inhibit any anomaly sensitive operations such as attitude adjustments, or take any other prudent action suggested by the potential of erratic conditions. The CEASE instrument is forecast to be packaged as a 4-inch cube weighing less than 3 pounds and dissipating less than 3 watts. (MM)

The preparation of Ground Support Equipment (GSE) hardware and software, as well as, attending to launch support concerns prior to and after APEX launch, constitutes the extent of the effort expended on Task 1 (the Photovoltaic Array Space Power Plus Diagnostics PASP Plus experiment). Previously written test software was refined and new code generated, in order to accommodate real-time instrument performance monitoring during ground contact periods, and to facilitate the display of historical instrument performance data after a downlink opportunity. Under Task 2, the Charging Hazards and Wake Studies CHAWS program, Amptek, Inc. acted largely in a consultative and support role to PL/GPSG during this report period. Under Task 3 (the Space Wave Interactions with Plasmas Experiment SWIPE) gse hardware was completed, and software was written and tested, for the electronics module of the EPI instrument on the OEDIPUS-C program. Two flight boxes are now in-house, fully assembled. Flight software for the constituent elements within the instrument was completed, and instrument functionality was fully exercised and checked. No additional change is envisaged to either hardware or software at this time.

Under Task 1, the Photovoltaic Array Space Power Plus Diagnostics PASP Plus experiment, encompassing most of Amptek's effort in the report period, Amptek has: (1) designed and built the experiment Controller; (2) provided an Electrostatic Analyzer (ESA), two QCMs, and three calorimeters (CALs); (3) worked with PL/GPSP on testing and integrating PASP Plus into the APEX satellite; and (4) provided Ground Support Equipment for spacecraft integration and mission operation. The Controller is comprised of a central processing unit, an array biasing and electrometer unit, an array I-V curve measurement unit, a power conversion unit, and interfaces to the 16 array modules, ten PASP Plus instruments (not including the Dosimeter), and the APEX spacecraft. The PASP plus Controller and ten other instruments it controls Sun Sensor, Langmuir Probe, ESA, Transient Pulse Monitor (with sensors), Electron Emitter, 2 QCMs, 3 CALs are described in detail, giving size (dimensions), weight, data rates and outputs, and input power requirements. On Tasks 2 and 3, at a much lower level of effort, Amptek supported PL/GPSP's work on the Charge Hazards and Wake Studies CHAWS experiment (O to -5000 V sweep power supply and engineering assistance) and on the S co Wave Interactions with Plasmas Experiment SWIPE (instrument definition).... Photovoltaic array space power plus diagnostics, PASP Plus, Charge hazards and wake studies, CHAWS, Space wave interactions with plasmas experiment, SWIPE.

As the size and sophistication of spacecraft have increased, anomalies in operational performance caused by the interaction of the energetic- particle population and the spacecraft have likewise increased. The Compact Environmental Anomaly Sensor (CEASE) is being developed as a small, low-power device to monitor space weather and provide autonomous warning of conditions that could cause operational anomalies. Based on the sensor-design and trade-off studies for CEASE, a dosimeter set consisting of solid-state detectors behind aluminum absorbers (of several thicknesses) has been chosen. The outputs of the detectors are fed into algorithms that warn of certain anomalies: (1) surface dielectric charging, (2) deep dielectric charging, (3) total radiation dose behind 0.035 g/cm to the 2nd power, (4) total dose behind 0.41 g/cm to the 2nd power, and (5) single event upsets. From seven quantities derived by algorithm processing, eight warning levels (1, 3, 100...3000 x base) are obtained for each of the five anomalies. Level flags can then be selected for a particular application. For such a CEASE instrument, we estimate a volume of 64 in to the 3rd power (4-inch cube), a weight of 2 pounds, and power dissipation of 2 watts., Prepared in cooperation with SAIC NW, Bellevue, WA.

Particle correlation techniques used with pulse counting energetic particle detectors are reviewed. Three methods are proposed for use on an electrostatic analyzer to be flown on the Space Shuttle Tethered Satellite System 1 mission.

The local environmental conditions that a spacecraft operates within may induce occasional anomalous behavior that can impact reliability and performance. The Compact Environmental Anomaly Sensor (CEASE) is an instrument being developed to detect local environmental perturbations and provide the host spacecraft with various anomaly alerts along with confidence factors that allow the host spacecraft to conduct its operations in a manner to minimize these anomalous responses or to flag data as suspect due to local conditions. This report covers the first year of a feasibility study of this instrument., Prepared in cooperation with SAIC NW, Bellevue WA.

Flight prototype sensor systems using spherical sections and electrostatic deflection have been developed, fabricated, tested and calibrated. The detectors measure the flux of ions and electrons over a 100 deg x 10 deg angular fan and in 32 discrete energy levels from 10 eV to 10 KeV. This study describes the sensor system design for an instrument package for shuttle flight as well as a corrrelator to look for wave-particle interactions. Operating procedures for a 2.4 Gigabyte Flight Data Recorder are included.

Flight prototype sensor systems using spherical sections and electro static deflection are being developed, fabricated, tested and calibrated. The detectors will measure the flux of ions and electrons over a 100 deg x 10 deg angular fan and in 32 discrete energy levels from 10 eV to keV. This report describes the sensor system design for an instrument package for shuttle flight as well as a correlator to look for wave-particle interactions.

Flight prototype sensor systems using spherical sections and electrostatic deflection are being developed, fabricated, tested and calibrated. The detectors will measure the flux of ions and electrons over a 100 degree x 10 degree angular fan and in 32 discrete energy levels from 10 eV to 10 KeV. This report describes the sensor system design for an instrument package for shuttle flight as well as studies being performed investigating the feasibility of using strip detectors to produce multiangular solid state detector for high energy particles and the use of time of flight techniques for mass determination and a correlator to look for wave-particle interactions. (RH)