ElectroStatic Analyzer ESA ESA Team Space Sciences Laboratory

. Electro-Static Analyzer (ESA) ESA Team Space Sciences Laboratory University of California – Berkeley THEMIS INSTRUMENT PER ESA-1 UCB, August, 2005

ESA with IDPU F 1 Shown in Instrument Suite F 1 THEMIS INSTRUMENT PER ESA-2 UCB, August, 2005

ESA Systems Status F 1 - F 3 assembled, coated and Calibrated F 4 -F 6 partially complete; ESA Core Subsystem status • • • Preamp Boards 5 complete and tested, 1 partial (Actel not loaded) EESA Anodes IESA Anodes 4 complete with flight MCPs, 2 more in testing • • LVPS Sweep Interface Boards HV Supplies HV Mother Boards 6 complete units fully tested. (SWRI) 3 complete and tested, 2 in final testing, 1 ETU 5 pairs complete and tested, 1 ETU 3 complete and tested, 2 in final testing, 1 ETU • Mechanical All 6 analyzer mechanical assemblies complete (cover release mechanisms and boxes complete. ) THEMIS INSTRUMENT PER ESA-3 UCB, August, 2005

Overview Mission Requirements as listed in the MRD are presented: • Items marked in green are either completed & tested or verified by design. • Items marked in yellow are either incomplete or yet to be verified. • Items marked in blue are ‘work in progress’ or ‘still to do’ THEMIS INSTRUMENT PER ESA-4 UCB, August, 2005

Mission Requirements REQUIREMENT ESA DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. Lifetime has been considered in all aspects of ESA Design. System design and components are direct copy of FAST ESA (still fully functional after 7 years on orbit) IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5 mm of Al, RDM 2) Compliance. Common Parts buy for Instrument Payload. Lower radiation dose than FAST ESA has experienced without problem. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. FAST components were selected for SEE and latch-up immunity and are verified by flight history. IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget. xls Compliance. 2. 84 kg Allocated before reserve. 2. 90 Projected. IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget. xls Compliance. 2. 0 W Allocated. 1. 8 W Measured. Power will increase slightly thru mission owing to MCP aging. IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. ESA is designed and will be tested to comply with the ICD requirements. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. ESA is designed and will be tested to comply with the ICD requirements. THEMIS INSTRUMENT PER ESA-5 UCB, August, 2005

Mission Requirements REQUIREMENT ESA DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Contamination Control Plan. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan IN-19. All Instruments shall comply with all electrical specifications Compliance. THM-IDPU-001 Specification IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-105 ESA and SST Electronics Card (ETC) Specification. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-IDP-ICD-001 IDPU+ESA ICD REV AD, IDPU/ESA-to-Probe ICD. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification. THEMIS INSTRUMENT PER ESA-6 UCB, August, 2005

Science Requirements REQUIREMENT ESA DESIGN IN. ESA-1. The ESA shall obtain partial moments of the 3 D plasma electron and ion distributions in the magnetotail plasma sheet Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN. ESA-2. The ESA shall measure differences in velocity and ion pressure between probes in the magnetotail plasma sheet Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN. ESA-3. The ESA shall measure ion and electron distributions that are associated with the current disruption process Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN. ESA-4. The ESA shall be capable of measuring ion moments and differences of those moments in the magnetosheath and solar wind. Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. Solar wind moments will be limited to a specific range of velocity and density consistent with instrument saturation. THEMIS INSTRUMENT PER ESA-7 UCB, August, 2005

Performance Requirements REQUIREMENT ESA DESIGN IN. ESA-5. The ESA shall measure ions and electrons over an energy range of 10 e. V to 30 ke. V Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-6. The ESA energy sampling resolution, d. E/E, shall be better than 25% FWHM for ions and electrons Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-7. The ESA shall be capable of measuring ion and electron energy flux of 10^4 to 10^9 ke. V/cm^2/s/Str/ke. V Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-8. The ion ESA geometric factor shall be attenuated in the solar wind to avoid saturation. Waived. High fluxes of solar wind ions will be accommodated by small area anodes in the equatorial view directions. IN. ESA-9. The ESA shall supply partial energy moments at one spin time resolution. Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-10. The ESA shall have a 180 deg. elevation FOV with a minimum angular resolution of 22. 5 deg. Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-11. To resolve the solar wind, the ESA shall have a FOV with enhanced resolution of ~ 6 deg. Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-12. The ESA shall produce measurements of particle distributions over the entire 4 pi steradian field of view in one spin period. Compliance. FM 2 Science Calibration: 15 -16 July FM 3 Science Calibration: 10 -12 Aug IN. ESA-13. ESA calibration shall ensure <20% relative flux uncertainty (not including statistical uncertainty) over the ranges defined above. THEMIS INSTRUMENT PER Compliance. Satisfied by on-orbit calibration of plasma density with wave measurements. ESA-8 UCB, August, 2005