THEMIS INSTRUMENT SUITE FM2/FM3 PRE-SHIP REVIEW FM4/FM5 PRE-ENVIRONMENTAL REVIEW INTRODUCTION

1. THEMIS INSTRUMENT SUITE • FM2/FM3 PRE-SHIP REVIEW • FM4/FM5 PRE-ENVIRONMENTAL REVIEW • INTRODUCTION • Davin Larson • Thomas Moreau • SST Team • University of California - Berkeley

2. Outline • Summary of SST Status at FM1 PSR • FM1-5 Configuration by SN • End-Item Data Package • Final Test and Cal Results vs. Requirement Fulfillment • Open Items

3. Flight Configuration • Current flight configuration of sensors and DAPs for all flight units.

4. FM1 EIDP: Sensors • THEMIS SST Sensor: (Sensor1:Binder #33; Sensor2: Binder #34) • Electrical Assembly • Schematics • Electrical Assembly Records • Rework/Repair history • Electrical test results • QA signoffs • Mechanical Assembly • Mechanical drawings • Vibration test results • Thermal Vac test results • Assembly Records. • Special TVAC Acceptance Test Data.

5. FM1 EIDP: DAP • THEMIS SST DAP: (Binder#2) • Schematics • Electrical Assembly Records • Rework/Repair history • Electrical test results • QA signoffs

6. SST Vibration Testing (Pictures of Probe 2 units)

7. SST Acceptance Level Dynamic Test

8. SST Acceptance Level Dynamic Test • Per UCB THEMIS Document THM-SST-PRC-002 • All 3 Axes • Sine Survey, 0.5 G, 5 – 2000 Hz • Sine Strength per Swales TM2430-RevD, 29 November 2004 • Random • Per Swales Document TM2430-RevD • 12.51 G RMS • 1 min duration per axis • All Vibration Testing Performed at Quanta Laboratories • Retesting (if required) • ‘Workmanship Shake’ • Validate any design changes following original Flight build shake • Validate rework of any failures on previous vibration test • Entire vibration protocol, single axis only Acceptance Sine Strength Specification SST Flight Unit Acceptance Level Random Specification

9. SST Acceptance Level Dynamic Test • Deviations from Test Specification (Notching/Force Limiting/Aborts) • None • SST First Natural Frequency: 213 Hz (Requirement: >75 Hz) • Good Sine Survey Consistency from Unit to Unit (within 10 Hz) • Retesting due to Hardware Redesign • Reinforcement plate bond failure led to stress fracture formation on SST 001 support structure • Resolution: Support structure redesigned and strengthened in high stress areas • Flight-like ETU passed qualification level dynamic test performed on 2 Feb 2005 • Flight Unit Status • Flight Units for Probe 1 scheduled for 2nd vibration test upon completion of suite level testing • Flight Units for Probe 2 completed vibration testing on 22 April 2005 • Flight Units for Probe 3 scheduled for vibration testing on 6 May 2005 X-Axis Testing Y-Axis Testing Z-Axis Testing

10. SST TVAC Testing

11. Thermal Profile Procedure: THM-SST-PRC-003

12. SST -Magnetic cleanliness • SST Magnetic Cleanliness Testing Status • All units have been tested and are nominal. • Sensors 3,4,6,8,7,9,11 and 12 should be retested following recent vibration tests.

13. SST Requirements • SST Mission Requirements Fulfillment: • FM1 MR fulfillment noted in THEMIS Verification Matrix (see MSE Presentation) • Integrated SST and component parts compliant with mission requirements

14. Open PFRs

15. PFR - 97 -Resolution • Options to reduce noise susceptibility: • Improve sensor internal shielding. - Done • Remove caps on line. - Done • Switch power and return lines. - Unnecessary • Eliminate heater altogether. – Unnecessary • Resolution- • Identified as a poorly grounded Al shield tape. • Replaced with properly grounded Cu shield. • This was a rather difficult problem to track down because it would only happen to some sensors (not the ETU) after several hours under vacuum and was only observable with an injected noise source.

16. PFR - 101 -Resolution • SMA (partial) failure on FM3 sensor • Occurred as a result of mishandling during reassembly. • Discovered almost immediately, repaired same day. • Bench tests (in air) were successful • Tests in suite T/V were successful. • Awaiting retest of 1 cycle to –50C.

17. Results of Testing/Calibration • Energy Threshold vs temperature measured and acceptable • Energy resolution acceptable (<13 keV at 5C). • Detector gain measured and is stable over temperature. • Channel crosstalk measured and acceptable (<20 keV) • Attenuator functions over full operational Temp range. • Heater/Thermostat Functional at < -50 C *! • Magnetic moments measured and deemed acceptable. • End to End performance verified. • (*!) Noise susceptibility from BAU is very low now

18. FM 1 - Update • SPB (Sun Pulse Blockout) Mod#2 has made the sensor susceptible to external noise sources, in particular, noise on the Heater return line. (this line originates on the BAU). Risk: moderate. Update: replacement of heater shielding has made susceptibility extremely low. Risk: very low. • SST sensors 01 and 02 (FM1) require final qualification vibration test (Done) and subsequent recalibration (mostly done) /functional testing (Done) . Risk: very low - 7 sensors have already passed qual vibration tests.

19. Open Issues • Still left to do: • Ion calibration of sensors 4, 6, 7, 9, 11 and 12 (½ of P2, ½ of P3, P4 and P5) • Thermal Vac re-test of Sensor 6 (½ of P3 ) • Thermal Vac test of Sensors 11 & 12 (P5)

20. Miscellaneous Calibration Data

21. Response to electron gun FLIGHT#2 – S3A Foil 22keV 26keV 30keV 34keV 38keV 42keV 46keV • Energy threshold measured < 30keV at cold temperature

22. Response to low-energy proton FLIGHT#2 – S3B Open 30keV 35keV 75keV 100keV 150keV • Protons measured above 30keV (at room temperature) • Energy threshold expected < 30keV at cold temperature

23. Response to low-energy oxygen FLIGHT#2 – S3B Open 60keV 75keV 100keV 150keV • Oxygen measured above 60keV (at room temperature) • Energy threshold expected < 60keV at cold temperature

24. Noise Threshold Vs. Temperature