LRO System Requirements Review Lunar Exploration Neutron Detector (LEND) Requirements & Implementation

1. LRO System Requirements ReviewLunar Exploration Neutron Detector (LEND)Requirements & Implementation Igor Mitrofanov Principle Investigator Russian Institute for Space Research

2. Institute for Space Research, Russia Sternberg Institute of Astronomy, Russia Joint Institute of Nuclear Research, Russia University of Maryland, USA NASA/Goddard Space Flight Center, USA University of Arizona, USA Catholic University of America, USA Computer Science Corporation, USA Institutions of LEND Instrument Team

3. LEND Science Overview and Theory of Operations STN 1 STN 2 SETN STN 3 LEND sensors of STN1-3 and SETN detect thermal neutrons and epithermal neutrons to characterize Lunar Radiation Environment. STN1 and STN3 operates as Doppler filter for thermal neutrons from front side and back side of LEND SETN and STN2 have open fields of view LRO velocity vector

4. LEND Science Overview and Theory of Operations LEND sensor SHEN detects high energy neutrons at 16 energy channels from 300 keV to >15 MeV to characterize Lunar Radiation Environment SHEN has narrow field of view about 20-30 SHEN

5. LEND Science Overview and Theory of Operations LEND collimated sensors CSETN1-4 detect epithermal neutrons with high angular resolution to characterize spatial variations of Lunar Neutron Albedo, which depend on content of hydrogen in 1-2 m of the regolith epithermal neutrons CSHEN 2 CSHEN 1 H CSHEN 3

6. LEND Science Overview and Theory of Operations LEND collimated sensors CSETN1-4 and SHEN detect epithermal neutrons and high energy neutrons with high angular resolution to test water ice deposit on the surface epithermal neutrons water ice high energy neutrons CSHEN 2 CSHEN 1 CSHEN 3 SHEN

7. LEND Heritage Plastic Anti-coincidence for Sensor of HEN Collimator of neutrons Larger counters of neutrons HEND/Odyssey is LEND prototype with few design changes

8. LEND Heritage LEND electronics has only one design change in respect to HEND Design Change

9. LEND Documentation Project: LRO Program Requirements Document; ESMD-RLEP-0010 LRO Mission Requirements Document; 431-RQMT-00004 LRO Technical Resource Allocations; 431-RQMT-000112 Instrument: Instrument Payload Assurance Implementation Plan LEND PAIP 01 Instrument to Spacecraft Interface Control Documents Mechanical 431-ICD-000088 Thermal 431-ICD-000119 Electrical 431-ICD-000097 Data 431-ICD-000107 Instrument Requirements Document LEND IRD 01 Contract documents with Russian Federal Space Agency Draft of LEND Implementation Agreement between NASA and FSA

10. LEND Mission Level Requirements

11. LEND Instrument System Level Requirements

12. LEND Instrument System Level Requirements

13. LEND Instrument System Level Requirements

14. LEND Instrument System Level Requirements

15. LEND Data Product Traceability

16. LRO Requirements Driven by LEND

17. LEND Constraints on LRO Example

18. LEND Block Diagram

19. LEND Development Flow Integration tests onboard LRO LRO Integration Stages of LEND development Acceptance tests for LRO environment requirements Qualification tests for LRO environment requirements LRO Env. Req. Laboratory tests with neutron sources, verification tests for LRO environment requirements Design Req. Laboratory tests with neutron sources and numerical simulations Functional Req. LEND units LEND FU02 LEND FU01 LEND LU LEND EU LEND QU

20. List of Procedures and Verification Tests • ReliabilityAnalyses (RA) • Failure Modes, Effects and Criticality Analysis (FMECA) • Electronic Parts Stress Analysis (PSA) • Thermal Stress Analysis • Structural Stress Analysis • Single Event Effects Analysis (SEE) • Screening of all electrical, electronic and electromechanical parts (SEEE) • Preparation of Confirmation Lists of Material and Components (CLMC) • Environmental Requirements (ER) • Radiation durability analysis • Random vibration and shock tests • Thermal vacuum test • Electromagnetic compatibility tests • Thermal cycling life test • Contamination Control (CC) • Preparation of Problem/Failure Anomaly Report (PFAR) • Accumulation of Hardware Operating Hours prior delivery (HO)

21. LEND Current Status • Trade studies which have been closed • Concept of LEND configuration • Electrical interface design • Selection of sensors and major electronic components • Concept of thermal design • Concept of mechanical design • Manufacturing documentation for LEND LU • Cooperation in Russia for LEND manufacturing • Outgoing trade studies • Optimization of collimator unit of SETN 1-4 for the best sensitivity for 5 km radius spot at pole with enhancement of H • Optimization of narrow field of view for detector of high energy neutrons SHEN • Thermal model of instrument • Analysis currently being performed • Numerical model of Moon neutron albedo at different energy ranges • Estimation of instrument fundamental frequency ( > 75 Hz) • Software for data processing of LEND LU • Hardware currently in development • Mechanical elements of LEND LU • Collimator units of LEND LU • Electronic boards of LEND LU • 7. What is the status of the agreements?

22. LEND Development Milestones

23. Summary • LEND is developing in response to RLEP-LRO M010, M070 and M110: corresponding flows • from LRO Mission requirements to LEND Functional Requirements and Design Requirements are • well understood • Data Products of LEND are defined, which correspond to RLEP-LRO M010, M070 and M110 • LEND development process ensures that LEND Flight Unit will provide defined Data Products • LEND accommodation on LRO ensures that LEND will be able to provide defined Data Products • There is only one additional requirement to LRO driven by LEND (measurements at different • angles from Nadir to Horizon) which is not presented in the mission baseline. This operation • provides additional data products on Lunar Radiation Environment (angular distribution of • neutron component) • 6. LEND team is ready to move to the preliminary design stage • 7. What is the status of the agreements?