1. 1 MAVEN PFP ICDR May 23-25, 2011 Mars Atmosphere and Volatile EvolutioN (MAVEN) Mission Solar Wind Electron Analyzer (SWEA) Critical Design Review May 23 -25, 2011 Dave Mitchell SWEA Lead

2. 2 MAVEN PFP ICDR May 23-25, 2011 IRAP / UCB-SSL Collaboration IRAP (CESR), Toulouse Analyzer MCP Anode HVPS SSL, Berkeley Pedestal Digital / FPGA LVPS (same as for STEREO SWEA)

3. 3 MAVEN PFP ICDR May 23-25, 2011 SWEA Team – SSL David L. Mitchell (Instrument Lead) Paul Turin (Mechanical) Ellen Taylor (Electrical) Chris Smith (Thermal) –with support from John Hawk at NASA-GSFC Dorothy Gordon (FPGA) Peter Harvey (FSW [PFDPU]) Peter Berg, Selda Heavner (Power Supplies) Tim Quinn (GSE) Steve Marker (Facilities) Daniele Meilhan (Scheduling) Kate Harps, Jim Keenan, Misty Willer (Purchasing, Contracts)

4. 4 MAVEN PFP ICDR May 23-25, 2011 SWEA Team – IRAP Christian Mazelle (Lead Co-I) Jean-Jacques Thocaven (PM, Electronics) Jean-André Sauvaud, Dominique Toublanc (Co-Is) Jean Rouzaud (Mechanics, Environmental tests) Andrei Fedorov (Detector simulations, Calibrations) Philippe Rouger (Electronics) Eric Lecomte (Integration, Coating) Qiu Mei Lee (Documentation) David Moirin BTS Industrie (Quality Assurance) TBD (CNES Technical Assistance for AIT) starting in April. Claude Aoustin (former CESR Technical Manager, expert) punctual assistance by Jean-Louis Médale (retired; expert on electronics) CNES can bring expert persons on request (components, EMC…)

5. 5 MAVEN PFP ICDR May 23-25, 2011 SWEA Documentation Performance Requirements –MAVEN-PM-RQMT-0005, Mission Requirements (Level 2) –MAVEN-PFIS-RQMT-0016, PFP Requirements (Level 3) –MAVEN-PF-SWEA-002, SWEA Specification (Level 4) Differences from STEREO SWEA –SWEA_STEREOtoMAVENChanges Interface Documents –MAVEN-PF-SWEA-001I_CESRtoSSLICD (analyzer to pedestal) –MAV-SWE-ICD-001 SWEA MICD (pedestal to spacecraft) –MAVEN_PF_SYS_0xx, PFP interfaces and specifications Environments –MAVEN-SYS-RQMT-0010 (Environmental Requirements Document) –MAVEN_ESC_specification (electrostatic cleanliness) Software –MAVEN_PF_FSW_002 –MAVEN_PF_SWEA_012A_FPGA_Specification (Level 5)

6. 6 MAVEN PFP ICDR May 23-25, 2011 SWEA pre-CDR Peer Review Held at IRAP, Toulouse, March 28-29 PFPRRFA01: Planetary Protection Implementation Plan – STATUS: Submitted Statement of Concern: IRAP may be unnecessarily implementing more PP activities than MAVEN required and using resources that they may want to apply elsewhere. Recommended Action: Clarify the required PP activities and update the PFP Contamination Control Plan to reflect what will be done Originator: N. Jedrich / GSFC PFPRRFA02: Assays – STATUS: Submitted Statement of Concern: Assays, as part of planetary protection implementation, and the analysis of the samples is not well defined. Recommend Action: Define, in the SSL contamination plan, who will take the assays, how often, and where they will be analyzed during AIT at IRAP. Originator: N. Jedrich / GSFC

7. 7 MAVEN PFP ICDR May 23-25, 2011 SWEA Science David L. Mitchell May 24, 2011

8. 8 MAVEN PFP ICDR May 23-25, 2011 4.1.8: Solar Wind Electrons Baseline: MAVEN shall determine flux and velocity distributions of solar wind, magnetosheath and ionospheric electrons from 10-1000 eV with an energy resolution sufficient to distinguish ionospheric photoelectrons from solar wind electrons and ability to resolve magnetic cusp horizontal spatial scales. Better than 30 o angular resolution; better than 20% energy resolution. Rationale: Electron energy-distribution measurements determine the electron impact ionization rates, allow distinction to be made between the different regions created by solar-wind interactions with the upper atmosphere, determine magnetic topology near magnetic cusps, and constrain behavior of auroral electrons. MAVEN Level 1 Requirements

9. 9 MAVEN PFP ICDR May 23-25, 2011 SWEA Science Goals Magnetic Topology & Plasma Regime Crustal Magnetospheres/Cusps Draped Field Lines o o o

10. 10 MAVEN PFP ICDR May 23-25, 2011 SWEA Science Goals Electron Impact Ionization Magnetic Pileup Region Ionosphere MGS MAG/ER

11. 11 MAVEN PFP ICDR May 23-25, 2011 Photo-ionization of CO 2 by solar h @ 304 Å Escape associated with heavy ions (M> 16) 2.35 R M Shadow PEBESCAPE MPB h -electrons R (MSO) 5 4 3 2 1 0 -3-2012 X (MSO) Mars Express SWEA Science Goals

12. 12 MAVEN PFP ICDR May 23-25, 2011 of the sensor at low energy can be controlled by varying the voltage bias U 0 between the internal and external grids: where is the energy resolution for zero bias (0.175) and is the incident energy of the electron Thus for 1.5x finer energy resolution (and 2x smaller GF), we apply Variation of Energy Resolution* Works for apoapsis and side segments in all orbit scenarios. Works for Sun-Velocity mode at periapsis (~50% of orbits). Does not work for deep dips. Works for apoapsis and side segments in all orbit scenarios. Works for Sun-Velocity mode at periapsis (~50% of orbits). Does not work for deep dips. / *Not needed to meet Level 3 requirements

13. 13 MAVEN PFP ICDR May 23-25, 2011 REQUIREMENTSWEA DESIGN PF65: SWEA shall measure energy fluxes from 10 4 to 10 8 eV/cm 2 -sec-ster-eV with no worse than 25% precision Compliance. SWEA designed to measure energy fluxes from 10 3 to 10 9 eV/cm 2 -sec-ster-eV. PF66: SWEA shall have a geometric factor > 0.005 cm 2 -sterCompliance. Geometric factor from simulations and laboratory calibrations of STEREO SWEA yield a geometric factor of 0.01 cm 2 -ster. PF67: SWEA shall measure electrons from 10 – 1000 eVCompliance. SWEA analyzer range is 5 eV to 6 keV, with full deflections up to 1.6 keV. PF68: SWEA shall have energy resolution dE/E of at least 25%Compliance. SWEA designed with an energy resolution of 18%, which can be adjusted down to 9% for energies below 50 eV. PF69: SWEA shall have time resolution of at least 20 secondsCompliance. SWEA completes a full analyzer and deflector sweep cycle in 2 seconds. SWEA bit rate supports 4-second resolution in ionosphere mode. PF70: SWEA shall have angular resolution of at least 45 degreesCompliance. SWEA design provides 22.5-degree resolution in azimuth, and better than 14 degree resolution in elevation. PF71: SWEA shall have a FOV which covers at least 50% of the sky Compliance. SWEA FOV (360 o x 130 o ) covers 90% of the sky, minus spacecraft blockage (8%), for energies up to 1.6 keV. PF107: SWEA shall have an in-flight calibration procedure to determine its absolute sensitivity to within 25%. Compliance. STATIC absolute sensitivity is determined from START and STOP event ratios. SWEA is cross calibrated with STATIC in the sheath. PF Level 3 Requirements

14. 14 MAVEN PFP ICDR May 23-25, 2011 In-Flight Calibration Pre-launch: SWEA must have the right dynamic range to handle expected flux range at Mars (10 years of experience with MGS ER) –The energy and angle responses and geometric factor (minus detector efficiency) are determined within ~10% by calibration and simulation. –Detection efficiency depends on MCP efficiency, which varies with time. In-flight: Absolute START and STOP efficiencies for STATIC are determined in the sheath from event ratios: (START with STOP) Valid and (STOP with START) Valid START Valid STOP Valid Combine this with mechanical analyzer geometric factor from simulations to get absolute sensitivity. With STATIC as the reference, calibrate SWEA and SWIA by determining total plasma density in the sheath.

15. 15 MAVEN PFP ICDR May 23-25, 2011 Data Products FPGA provides a single science data product to the PFDPU –Counts per accumulation interval for each of the 16 anodes (as a function of analyzer and deflector sweeps) –Complete measurement sequence takes 2 seconds. PFDPU computes three data products, with cadence depending on altitude Solar Wind Mode altitude > 500 km 544 bps Energy spectra every 16 sec Pitch angle distr. every 16-32 sec 3D distributions every 64 sec Ionosphere Mode altitude < 500 km 1216 bps Energy spectra every 4 sec Pitch angle distr. every 4-8 sec 3D distributions every 64 sec

16. 16 MAVEN PFP ICDR May 23-25, 2011 Spacecraft Accomodation SWEA axis parallel to SC Z when deployed Boom location: Separation from s/c potentials Large, clear field of view Sensor head in shadow Electronics box in sunlight FOV: 360 o x ±65 o

17. 17 MAVEN PFP ICDR May 23-25, 2011 SWEA Resources SWEA Mass ComponentPDR CBE (kg) CDR CBE (kg) Electrostatic analyzer0.7030.783 MCP+Anode board0.070 Preamp board0.080 HV power converter0.150 LV power converter0.2000.120 Digital board0.2000.150 Electronics housing0.1500.425 Connector, Cabling0.045 Total 1.5981.823 Allocation 1.942.10 Contingency 21%15% SWEA Power ComponentPDR Average (mW) CDR Average (mW) Front-end electronics565 Digital electronics160105 Total Secondary725670 SWEA LVPS Eff. (75%)242223 PFDPU LVPS Eff. (90%)10799 Total1074992 Allocation1240 Contingency15%25%

18. 18 MAVEN PFP ICDR May 23-25, 2011 SWEA Electrical Ellen Taylor May 24, 2010

19. 19 MAVEN PFP ICDR May 23-25, 2011 SWEA Electronics Overview Block Diagram No major changes since PDR Digital Board Design and EM Verification LVPS Board Design and EM Verification EM Integrated Electronics Test Results –Digital Board/Analyzer –LVPS/Digital Board –LVPS/Digital Board/Analyzer to PFDPU Parts Stress Analysis, Parts Status and Issues Power Budget

20. 20 MAVEN PFP ICDR May 23-25, 2011 SWEA Electrical Block Diagram UCB IRAP/CESR

21. 21 MAVEN PFP ICDR May 23-25, 2011 Heritage and Design Similarities MAVEN SWEA digital board has direct heritage from STEREO SWEA: –Minor interface changes (separate connector to SC for temp sensor, heater and actuator, external PFDPU connector) –Changed interface logic to 3.3V from 5V (added translators 54ACT244 on FPGA outputs, UT54ACS164245SEI on pre-amp inputs to FPGA) –Minor FPGA part change (RT54SX72S from RT54SX32S) –Removed STE digital circuitry and interface –Removed latch-up circuitry –Minor part changes due to obsolescence, desire to have common parts buy and circuitry MAVEN SWEA digital board is very similar to MAVEN SWIA and STATIC: –FPGA and SRAM same as SWIA, different than STATIC –Housekeeping (HK MUX and ADC parts) same –Fixed and Sweep DACs same minus offset DACs need for STATIC

22. 22 MAVEN PFP ICDR May 23-25, 2011 Digital Board Design Command/Data Interface to PFDPU Accumulate counts from each of the 16 anodes Bin data for transfer to PFDPU Enable HVPS and MCP high voltage Control voltage sweeps for analyzer inner hemisphere and deflectors SRAM for storing lookup tables and accumulators Generate test pulses Control ADC and MUX to read instrument housekeeping monitors Note: Digital board does not control heaters (S/C) or cover actuators (S/C)

23. 23 MAVEN PFP ICDR May 23-25, 2011 Digital Board Status Board Built and Loaded (MAVEN-PF-SWE-SCH-001 Rev 16)

24. 24 MAVEN PFP ICDR May 23-25, 2011 Digital Board EM Verification Digital Board Test per MAVEN-SWE-PROC-001 verifies: TLM/CMD connectivity with MISG Power distribution to test points Power consumption by service Power generation (+/-4V reference for DACs) Polarity on all polarized capacitors Analog (raw and converted) and digital housekeeping Test pulser generation and frequency High voltage allow, arm, enable Fixed and Sweep DAC control Anode Count Products (message receipt) Soft Reset

25. 25 MAVEN PFP ICDR May 23-25, 2011 SWEA and SWIA FPGA Similarities Commonalities –Both require anode counting frontends –Both implement Command & Telemetry Interfaces (CDI functionality for receiving commands and sending messages) –Housekeeping Control and Message Format –Memory Control –Fixed and Sweep DAC Control –Timing Backbone (reconfigured to accommodate the different accumulation intervals) –Lookup table memory and control (Loader and Checksummer) –High Voltage turn-on is a protected command Differences –SWIA: 24 Anodes (14 WFOV and 10 NFOV) –SWEA: 16 Anodes –SWIA: 4 second cycle with 2304 Accumulation Intervals –SWEA: 2 second cycle with 488 Accumulation Intervals –SWIA Implements Products –SWEA Includes Operational Heater Control

26. 26 MAVEN PFP ICDR May 23-25, 2011 FPGA Block Diagram verified (self-test pending Rev2) pending Rev 2 removed, not required

27. 27 MAVEN PFP ICDR May 23-25, 2011 SWEA Test Pulser Data

28. 28 MAVEN PFP ICDR May 23-25, 2011 SWEA LVPS Design and Test DESIGN Converts regulated +28V from PFDPU to +28VA +/-10% (20mA Peak), +12VA +/-5% (8mA), +5VA +/-5% (10mA), -5VA +/-5% (10mA), -12VA +/-5% (10mA), +5VD +/-5% (40mA), +3.3VD +/-3% (10mA), +2.5VD +/-3% (10mA) TESTS PERFORMED Turn on Voltage Levels Load regulation Input Voltage Range Test Integration w/ Digital Board ONGOING/FUTURE TASKS Flight layout Stability tests Efficiency test Thermal test Test Procedure Parts Stress Analysis

29. 29 MAVEN PFP ICDR May 23-25, 2011 Integrated Digital/Analyzer Test Digital Board Integrated and Tested with EM Analyzer per MAVEN- PF-SWE-PROC-002: –Safe-to-Mate –Analog Housekeeping from Analyzer –Test Pulser –MCP High Voltage Enable –MCP HV Control –Non-Regulated HV Enable –Sweep DAC Control –Deflector and Vo Control –Anode Count Processing

30. 30 MAVEN PFP ICDR May 23-25, 2011 PFDPU Integration and Test PFDPU integration per MAVEN-PF-TP-003 tested: Safe-to-Mate Command Test Telemetry Test Power In-Rush Test LVPSDCBAnalyzer

31. 31 MAVEN PFP ICDR May 23-25, 2011 Mechanical Fit-Check Fit Check with Mechanical Chassis

32. 32 MAVEN PFP ICDR May 23-25, 2011 Electronic Parts Electronic Part Status: –Flight BOMs provided to Parts Engineer –Active parts provided by GSFC –With very little exception, flight active parts being used on EM UCB Part Stress Analysis (Digital Board, LVPS), using GSFC spreadsheet: –All capacitors, resistors and microcircuits derating guidelines at maximum voltage –CDR capacitors are rated at 50V, which does not meet the requirement to use 100V rating for low voltage applications, requires additional part lot testing –Have not completed spreadsheets for diodes, connectors, transistors IRAP Part Stress Analysis (Anode, Amplifier, HV): –Anode Board: Complete except for one resistor, waiting for manufacturer info –Amplifiers Board: Not done yet, but no concerns as it is 100% identical to STEREO –HV Board: 90% completed. Minor exceedances on derating: C12 (capacitor/MCP HVPS): 3kV allowed, 2.8 to 3.15kV applied C41 (capacitor/ HVNR): 30V allowed, 35V applied C24 & C25 (capacitor/ HVNR): 6V allowed, 6.7V applied D21, D22, D42, D43 (diodes): 56V allowed, 60V applied D44 (diode): may have surge current concern, need simulation to check D2, D10, D33 (diodes): 2250V allowed (reverse voltage), 2325V applied

33. 33 MAVEN PFP ICDR May 23-25, 2011 SWEA Front-End Electronics (IRAP) –HVPS Board High Voltage generation (2 kV) –2kV for deflectors & analyzer –3.5 kV for MCPs Voltage Scanning functions –Amplifier Board Charge amplifiers (A111F) –HV Coupling Board Interface between high/low voltage functions Collecting Anodes & Mechanical support for MCPs FM Amplifier Board All FM front-end boards currently in test.

34. 34 MAVEN PFP ICDR May 23-25, 2011 SWEA FM Front-End Electronics (IRAP) HV Coupling Board HV Board (all boards 11.2 cm diameter)

35. 35 MAVEN PFP ICDR May 23-25, 2011 HVPS Board Changes (STEREO  MAVEN) Increase Maximum Deflection Potential from 1.5 kV to 1.8 kV Review of transformer design to avoid saturation at 1.8kV Now able to supply 2kV Voltage ranges for Commands and Housekeeping were changed from Stereo Need to adapt some resistor values Values have been calculated and will be confirmed and adjusted (if necessary) by tests

36. 36 MAVEN PFP ICDR May 23-25, 2011 On Stereo: Crack problems during soldering of vertical capacitors Caused by excessive temperature gradient (pads too big) Solution: Apply solder at each corner and stick that remains PCB and capacitors warmed to 70 C before soldering HV Coupling Board Improvements

37. 37 MAVEN PFP ICDR May 23-25, 2011 SWEA Resources SWEA Power ComponentPeak (mW) Average (mW) Front-end electronics776565 Digital electronics149105 Total Secondary925670 SWEA LVPS Eff. (75%)308223 PFDPU LVPS Eff. (90%)13799 Total1370992 Allocation1240 Contingency25% Front-End Electronics Measured values from STEREO flight unit Digital Electronics Measured: ~ 70mW ETU FPGA only 6mA on 2.5V (15mW) Flight FPGA power will be ~ 3x this Calculated power using RT54SX72 power calculator for expected utilization is ~ 50mW Expected utilization < 75% Power slightly less than PDR estimate (1074mW)

38. 38 MAVEN PFP ICDR May 23-25, 2011 SWEA Mechanical Paul Turin June 15, 2010

39. 39 MAVEN PFP ICDR May 23-25, 2011 Exploded View SWEA detector head LVPS Pedestal housing Digital board Cover Board mounted SC harness and enable connectors HV enable plug Purge port (fitting TBD)

40. 40 MAVEN PFP ICDR May 23-25, 2011 Baseplate Vent port (screened for EMC) HV Enable plug (green tag item) SC harness connector Mounting holes (4) Balance mass opening

41. 41 MAVEN PFP ICDR May 23-25, 2011 SWEA EM on Pedestal EM

42. 42 MAVEN PFP ICDR May 23-25, 2011 Mechanical Changes from PDR Feet changed to reverse fasteners to thread into boom Purge fitting clocked 25 deg to improve access to connectors

43. 43 MAVEN PFP ICDR May 23-25, 2011 Margins First mode 197Hz

44. 44 MAVEN PFP ICDR May 23-25, 2011 SWEA Design Loads

45. 45 MAVEN PFP ICDR May 23-25, 2011 Key Mechanical Changes Scallop inner and outer hemispheres and top cap –Suppress secondary electron signal by factor of 3. Change coating of top cap from Nuflon to Cu 2 S –Avoid charging anomaly seen on STEREO. Metalize backs of deflectors and reduce area of exposed insulators (grid washers) –Minimize areas inside the analyzer that can become charged. Change positions of deflectors –Better deflection with flatter response.

46. 46 MAVEN PFP ICDR May 23-25, 2011 Surface Coatings SWEA parts plated with high-P electroless black-Ni top cover upper deflectortoroidal grid 10 cm Black Nickel: Conducting Non-magnetic High emissivity Survives atomic O

47. 47 MAVEN PFP ICDR May 23-25, 2011 SWEA EM Cal Chamber Testing Calibration utilizes a GSE that controls the instrument, the electron source, and the 3-axis manipulator, and records the data End-to-end testing: Analyzer  front-end electronics  digital electronics  data products Verify analyzer, deflector, and V0 voltage sweeps Verify commands, data and housekeeping products

48. 48 MAVEN PFP ICDR May 23-25, 2011 SWEA Integration and Test At IRAP

49. 49 MAVEN PFP ICDR May 23-25, 2011 AIT Facilities  Class 1000 clean room for MCPs and detector assembly (IRAP)  New class 100 clean room for Maven and ExoMars AITs  Vacuum chamber storage for Maven and ExoMars parts or sub systems.  Heating chamber for Maven and ExoMars hardware sterilization.  Small clean room for electronics gluing and coating (IRAP)  Vacuum chamber and particles beam in class 10K clean room  Thermal chambers (-60°C to +120°C) – IRAP  Class 100K clean rooms available at sub contractors (Comat, Microtec)

50. 50 MAVEN PFP ICDR May 23-25, 2011 Reference Documents MAVEN SWEA Performance Assurance Plan MAVEN SWEA UCB to CESR/IRAP Interface Control Document MAVEN PFP performance requirement MAVEN PFDPU to instruments ICD MAVEN – UCB Mission Assurance Implementation Plan (MAIP) Maven harness specifications Maven grounding specifications Maven latchup LET criteria (tech. Note - UCB)

51. 51 MAVEN PFP ICDR May 23-25, 2011 AIT Documentation As built lists (materials, EEE parts, processes) As built assembling procedures Environmental testing reports (if any) Log books Non conformity reports with appropriates corrective actions Photographic documentation of FM hardware Analysis reports (mechanical, electrical, …) Tests reports

52. 52 MAVEN PFP ICDR May 23-25, 2011 Cleanliness and Contamination Issues (1)  Microchannel plate cleanliness requirements (same as for Stereo) Sensitivity to humidity, dust & hydrocarbons 100-micron particles can create discharges and damage MCPs Outgassing near MCP to be avoided Special procedure to clean MCPs and restore properties  Permanent purging system installed on SWEA with dry nitrogen at 5 liters/ hour Plastic hermetic container filled with dry nitrogen acceptable for transportation (couple of hours) few hours without purge flow is possible in clean room environment MCPs or sensor equipped with MCPs is stored in vacuum at IRAP  Hermetic red tag cover on SWEA analyser can be removed only in a class 1000 clean room and has to be kept on SWEA analyser during I&T

53. 53 MAVEN PFP ICDR May 23-25, 2011 Cleanliness and Contamination Issues (2)  All mechanical parts are cleaned with IPA  Storage vacuum chamber purchased for SWEA parts during or after AIT.  Integration in clean rooms In subcontractors clean rooms (Comat or Microtec) for tests or preliminary assemblies Class 100 IRAP clean room with PP rules. Class 1000 IRAP clean room for MCPs and analyser  Parts or sub systems bakeout before assembly in class 100 clean room  Unit bakeout for outgassing before first calibration tests  SWEA analyser stored in vacuum before calibration or before delivery to UCB

54. 54 MAVEN PFP ICDR May 23-25, 2011 Cleanliness and Contamination Issues (3) New ISO8/ Class 100 vertical flux clean room purchased for MAVEN & ExoMars integrations. Agreement to follow SSL planetary protection AIV rules (R Bartlett, Oct 4th 2010) For analyser coating, coated samples are made in the same time for contamination tests. Document with specific AIV instructions wrt PP rules given to subcontractors. First step of AIV @ subcontractors premices, then parts are sterilized when delivered to CESR. Red protection cover redesigned for better use (Stereo experience) Subsystems or Hw transported in sterile bags during AIV Small vacuum storage purchased to store Hw or parts @1mbar during AIV or before delivery All steps in non-conformity with PP reported on unit log book.

55. 55 MAVEN PFP ICDR May 23-25, 2011 SWEA AIT Flow Chart Note: Stereo-SWEA Engineering model analyzer has been refurbished according to Stereo to Maven changes and modifications indications have been validated and given to SSL (See Andrei Fedorov report) Processes modified for Planetary Protection Boards assembly, soldering, harness fabrication

56. 56 MAVEN PFP ICDR May 23-25, 2011 SWEA sensor electronics and mechanical AIT Boards assembly, parts soldering Harnesses @ Microtec Sterilization: 72h @ 110°C Functional tests, tuning parts fixing Electronics integration, tuning parts soldering Quick functional test Thermal tests, test reports Electronics ready for instrument assembly Mechanical parts fabrication and control @ COMAT Mechanical verifications and tests (concentricity, mounting, ) Spheres + top cap coating @ Collini with contamination samples delivered External parts coating Black Ni @ SSL Cleaning / sterilization @ CESR Mechanical parts control and assembly test SWEA sensor mechanical assembly SWEA mechanics ready for instrument assembly Electronics ready for instrument assembly SWEA mechanics ready for instrument assembly

57. 57 MAVEN PFP ICDR May 23-25, 2011 SWEA sensor final integration Electronics ready for instrument assembly SWEA mechanics ready for instrument assembly SWEA sensor assembly internal connections First vacuum tests @ CESR big vacuum chamber Electronics disassembly Gluing, coatings SWEA sensor final assembly Functionnal verifications Ready for delivery

58. 58 MAVEN PFP ICDR May 23-25, 2011 SWEA Calibration Plan At IRAP Andrei Federov May 24, 2011

59. 59 MAVEN PFP ICDR May 23-25, 2011 The facilities consist of a big vacuum chamber (10 -7 torr operational vacuum) and several hardware and software layers: IRAP calibration facilities: Overview

60. 60 MAVEN PFP ICDR May 23-25, 2011 IRAP calibration facilities: Electron Gun Large Aperture Electron Gun produces uniform 9-cm-diameter electron beam up to 10keV energy. The beam total current is measured, and the beam spatial distribution is monitored.

61. 61 MAVEN PFP ICDR May 23-25, 2011 IRAP calibration facilities: Electron Gun The beam variation from the center to periphery is ~40%, but it is measured and taken into account in the calibration. Millimeters

62. 62 MAVEN PFP ICDR May 23-25, 2011 For MCP characterization we use an another electron gun producing about 4mm diameter pencil beam. IRAP calibration facilities: Electron Gun

63. 63 MAVEN PFP ICDR May 23-25, 2011 The experiment is mounted on a 3-D rotating and horizontally translating table IRAP calibration facilities: Manipulator

64. 64 MAVEN PFP ICDR May 23-25, 2011 All hardware controllers are working as independent processes (virtual instruments) with own displays and in the any number of computers (3 currently). The controllers communicate with each other and with central calibration program via Parallel Virtual Machine interface. The calibration program controls all VI's (commands to turn the instrument, commands to set instrument HV, etc) and read the data from the experiment. IRAP calibration facilities: Software

65. 65 MAVEN PFP ICDR May 23-25, 2011 The deflector plates positions were changed. The old STEREO configuration is shown as a blue dashed line. New design was checked by ray-tracing and calibration of the EM. It was done to increase the elevation range of the instrument. IRAP Calibration: First Results

66. 66 MAVEN PFP ICDR May 23-25, 2011 The ray-tracing simulation shows that we can extend the elevation range up to ±60°. The figure shows the angular responses for different D=Udefl/E. IRAP Calibration: First Results

67. 67 MAVEN PFP ICDR May 23-25, 2011 The response of the sensor as a function of the elevation angle and D=Udefl/E (on the top the same scale is expressed as Udefl/Uan). You see that maximal elevation angle is 60º. IRAP Calibration: First Results

68. 68 MAVEN PFP ICDR May 23-25, 2011 Upper figure: Normalized geometrical factor as a function of the Udefl/Uan. Compariso of the STEREO simulation results (black), ray tracing Berkeley results (red), IRAP ray- tracing (dashed blue) and calibration (solid blue). Low figure: Elevation angle as a function of the Udefl/Uan. The maximal elevation is expanded from 50º (STEREO) 60º. IRAP Calibration: First Results

69. 69 MAVEN PFP ICDR May 23-25, 2011 Flight model Calibration Plan 1. MCP Characterization: a. Will be made with a Pencil Beam Source with beam energy 1000eV b. MCP entrance (above zero grid) will be protected by +5V grid to suppress secondary electrons c. Count v. MCP bias will be measured d. One sector dead time will be measured

70. 70 MAVEN PFP ICDR May 23-25, 2011 Flight model Calibration Plan a. The main measurements will be made with a Large Aperture Electron Source with beam energy 1000eV b. Positive elevations and negative elevations will be made with different mechanical setup (direct SWEA position, and “upside down” position. c. In both cases the entrance point of electrons will be inside calibrated zone of the beam for all possible elevations. d. For each elevation (mechanical turn of the instrument) a full scan in Uan, Udefl, and Azimuthal angle will be made. (Beam energy is constant) e. The measurements for fixed Elevation = 0º and limited Azimuth = -20º to +20º will be repeated for E = 200, 500, 3000, 5000, and 10000eV

71. 71 MAVEN PFP ICDR May 23-25, 2011 SWEA Integration and Test At SSL David L. Mitchell May 24, 2011

72. 72 MAVEN PFP ICDR May 23-25, 2011 PFP I&T Flow

73. 73 MAVEN PFP ICDR May 23-25, 2011 SSL Integration and Test Facilities One of 5 Thermal Vac chambers at SSL Cleanroom (with 5 THEMIS probes) Magnetics Screening StationOne of 3 calibration chambers at SSL

74. 74 MAVEN PFP ICDR May 23-25, 2011 SWEA Verification PFP Verification Plan MAVEN_PF_SYS_023 PFP Verification Matrix MAVEN_PF_SYS_033 Maps requirements to verification tests –FRD, ERD, ICD Requirements Most SWEA Performance Requirements in the FRD verified during SWEA Instrument Calibrations ERD requirements verified during Environmental Tests

75. 75 MAVEN PFP ICDR May 23-25, 2011 SWEA I&T Plans at SSL SWEA Sensor delivered to SSL ~11/2011 –Will have been calibrated at IRAP –Includes verification of instrument sensitivity (PF66), flux range (PF65), energy range and resolution (PF67, PF68), angular resolution (PF70), and FOV (PF71). SWEA Integrated with SSL electronics –Interface verifications –Comprehensive Functional Test (CPT) Uses internal test pulsers outside of vacuum chamber Verify all possible modes of operation Verify all instrument commands –Chamber tests to verify no change in performance, sweeping modes, data products

76. 76 MAVEN PFP ICDR May 23-25, 2011 SWEA System-Level Testing End-to-end testing in vacuum chamber from analyzer, to front-end electronics, to digital electronics, to data products Calibration utilizes a GSE that controls the instrument, and the electron source, the 3-axis manipulator, and records the data Verify analyzer, deflector, and V 0 voltage sweeping modes –Provides verification of time resolution (PF69) –Verify sufficient precision and stability for “ionosphere mode” Test energy and angular response to check that instrument response matches expectations from IRAP calibrations and simulation –Verify energy/angle response –Check hemisphere concentricity –Determine relative anode/MCP sensitivity Verify data products

77. 77 MAVEN PFP ICDR May 23-25, 2011 SWEA Schedule EM I&T3/8/11 – 5/25/11 –Digital, LVPS, Analyzer electronics integration – Done. –PFDPU I&T – Done. –EM Test/Cal (Vac) to begin soon FM5/26/11 – 7/19/12 –May 2011: Analyzer mechanical assembly @ IRAP – In progress. (delayed because of black Ni coating) –May-June 2011: Front-end electronics testing @ IRAP – In progress. –July 2011: Analyzer I&T @ IRAP –Aug-Sep 2011: Analyzer calibrations @ IRAP –Jul-Aug 2011: Pedestal fab @ SSL –11/8/11: Digital, LVPS ready for I&T @ SSL –11/10/11: Receive FM Analyzer from IRAP –Jan-Feb 2012: FM assembly, test, cal @ SSL –Mar-Apr 2012: Schedule margin (9.4 weeks) –4/30/2012: Deliver SWEA FM for PF Package I&T