1. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 21 GLAST Large Area Telescope: Instrument Science Operations Center CDR Section 2 Requirements Jim Martin SLAC jfm@slac.stanford.edu 650-926-4895 Gamma-ray Large Area Space Telescope

2. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 22 LAT Specification Tree 55 Level II Requirements 379 Level III Requirements LAT LEVEL I II III

3. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 23 Level II Requirements Level II Science Operations6 Instrument Operations17 Analysis Software and Data Processing19 Interfaces3 Data Standards and Data Format Standards7 Availability and Reliability1 Automation1 Security1 TOTAL55

4. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 24 Driving Requirements  4.3.7- LAT Instrument Commanding –Generate LAT instrument commands and identify procedures to direct the safe upload of the commands.  4.3.9- LAT Instrument Flight Software –Maintain, update, and validate the operation and performance of the LAT flight software.  4.3.10 - LAT Instrument Simulator –Maintain an instrument simulator for validating and verifying changes to flight software and command procedures, and also for use in anomaly resolution.  4.4.1 - Level 0 Data Processing –Receive Level 0 data from the MOC post-pass and process the data into Level 1 event data within 24 hours of receipt from the MOC.  4.4.2- Real-time Housekeeping Data –Autonomously receive real-time housekeeping data in near real-time from the MOC and process the data for diagnostic use.  4.4.6 - Instrument Response Simulation –Develop and maintain software to simulate the detailed response of the LAT to charged particles and gamma rays.  4.4.5 - Event Reconstruction and Classification –Develop algorithms to interpret the subsystem responses, apply calibration constants, and to find and identify incident photons.

5. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 25 REQUIREMENTS – Level II – LAT-SS-00015 Science Operations #TitleSummaryVerification 4.2.1LAT Instrument Calibration Produce, monitor and update calibration constants for the instrument T 4.2.2Instrument Response Functions (IRFs) Generate IRFs needed for science analysisT 4.2.3LAT Instrument Performance Assess the LAT instrument performance and compare actual performance against predicted performance. T 4.2.4LAT Instrument Optimization Optimize the LAT instrument in response to in-flight changes in hardware as described in the ISOC Operations Plan, LAT-SS- 01378. T 4.2.5Performance RecordsArchive data on the performance and calibration of the LAT instrument. D 4.2.6Retrieval of Archived Records Retrieve archived performance and calibration data at a rate of at least 1 GB in 60 minutes. T

6. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 26 REQUIREMENTS – Level II – LAT-SS-00015 Instrument Operations – 1/3 #TitleSummaryVerification 4.3.1Health and Safety Monitoring Monitor the health and safety of the instrument. T 4.3.2Housekeeping DataProcess and analyze LAT housekeeping data. T 4.3.3Operating LimitsDefine the operating limits for the LAT instrument. T 4.3.4Anomaly ResponseMonitor for and respond to anomalous configurations or states. T 4.3.5Operations RecordsMaintain records of the operation and health of the LAT instrument. D 4.3.6LAT Instrument Configuration Maintain the status of on-board operating parameters and control the configuration of the LAT instrument. T

7. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 27 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.3.7LAT Instrument Commanding Generate LAT instrument commands and identify procedures to direct the safe upload of the commands. T 4.3.8Telemetry and Command Databases Develop and maintain command and telemetry databases used for generating LAT instrument commands and analyzing the health, performance, and operation of the LAT instrument. T 4.3.9LAT Instrument Flight Software Maintain, update, and validate the operation and performance of the LAT flight software. T 4.3.10LAT Instrument Simulator Maintain an instrument simulator for validating and verifying changes to flight software and command procedures, and also for use in anomaly resolution. D Instrument Operations – 2/3

8. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 28 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.3.11Mission OperationsProvide mission operation support for the LAT instrument. 4.3.11.1Command UplinkProvide instrument command uploads to the GSSC for on-orbit instrument operations and to the MOC during pre-launch test and early orbit periods. T 4.3.11.2Command SchedulingCoordinate LAT commanding schedules with the GSSC. T 4.3.11.3AnomaliesCoordinate the resolution of LAT instrument anomalies with the MOC. D 4.3.11.4Pre-Launch ActivitiesProvide personnel and facilities to support pre- launch interface and system test activities. D 4.3.11.5On-orbit CheckoutPerform initial tests and analysis of LAT instrument operation and performance during an on-orbit checkout period of 60 days. T 4.3.11.6Operational PeriodSupport an on-orbit operational lifetime of a minimum of 5 years following an initial period of on-orbit checkout. T Instrument Operations – 3/3

9. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 29 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.4.1Level 0 Data ProcessingReceive Level 0 data from the MOC post-pass and process the data into Level 1 event data within 24 hours of receipt from the MOC. T 4.4.1.1Data QualityEvaluate the quality of the Level 0 data and determine if retransmission of the data from the MOC is required. T 4.4.1.2Retransmitted Level 0 Data Process retransmitted Level 0 data within 24 hours of receipt from the MOC. T 4.4.1.3Duplicate Level 0 DataProcess Level 0 data received from the MOC that duplicates or overlaps portions of previously received Level 0 data. T 4.4.2Real-time Housekeeping Data Autonomously receive real-time housekeeping data in near real-time from the MOC and process the data for diagnostic use. T 4.4.3Unfiltered DataProcess unfiltered data generated by the instrument hardware trigger. T Analysis Software and Data Processing – 1/3

10. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 210 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.4.4Level 1 Data ProcessingMaintain a processing pipeline for event reconstruction and classification. D 4.4.5Event Reconstruction and Classification Develop algorithms to interpret the subsystem responses, apply calibration constants, and to find and identify incident photons. T 4.4.6Instrument Response Simulation Develop and maintain software to simulate the detailed response of the LAT to charged particles and gamma rays. T 4.4.7Level 2 Data ProcessingMaintain a processing pipeline for Level 2 analysis tasks that can be automated, such as searching for transient sources, monitoring the in-flight IRFs, and refining information about alerts for transient sources generated by the instrument. D 4.4.8Science Analysis ToolsDevelop and provide to the GSSC and LAT team science analysis tools to analyze Level 1 data. D 4.4.9Science Data FormatProvide Level 1 and Level 2 data to GSSC and the LAT team in an agreed upon format. T Analysis Software and Data Processing – 2/3

11. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 211 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.4.10LAT Mirror SitesProvide data to any associated international or domestic mirror sites provided as part of the LAT team efforts. D 4.4.11Data StorageArchive all raw data and processed data products for the duration of the mission. D 4.4.12Pre-launch Test and Calibration Data Archive LAT test and calibration data obtained during pre-launch testing. T 4.4.13AlertsReceive and process LAT alert messages.T 4.4.13.1Validating AlertsUse LAT science data to validate and refine the scientific alert information. T 4.4.13.2Submitting Alerts to GCN Transmit refined scientific alerts to the Gamma Ray Burst Coordinates Network (GCN). T 4.4.13.3Instrument AlertsReceive, process, and respond to LAT instrument alert messages. T Analysis Software and Data Processing – 3/3

12. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 212 REQUIREMENTS – Level II – LAT-SS-00015 Req't # TitleSummaryVerif. Method 4.5.1GSSC, LAT Team, and LAT Mirror Site Interface for Science Data Products Interface with the GSSC, LAT team, and LAT mirror sites to provide and receive science data products. D 4.5.2GSSC Interface for Operational Data Products Interface with the GSSC to provide and receive operational data products, including instrument commands. D 4.5.3MOC Interface for Operational Data Products Interface with the MOC to provide and receive operational data products. D Interfaces

13. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 213 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.6.1Coordinate SystemUse the J2000 inertial coordinate system as the basis for identifying and reporting celestial objects and of communicating pointing directions. T 4.6.2Use of Metric UnitsPer NASA policy directive NPD 8010.2B, use metric in all data processing and design calculations in the LAT ISOC. T 4.6.3Time BaseUse UTC as the time base for operationsT 4.7.1Communications Format and Protocol Employ the standard communications format and protocol as recommended by CCSDS for telemetry and telecommands. T 4.7.2Variable Length PacketsAccept and accommodate variable CCSDS length packets for science, housekeeping, and alert data. T 4.7.3Software Upload FormatsFormat software uploads in blocks as specified by the MOC. T 4.7.4Science Analysis Tools Formats Adhere to standards that ensure software portability, independence of vendor and compatibility with existing multi-mission high energy astrophysics tools. D Data and Data Format Standards

14. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 214 REQUIREMENTS – Level II – LAT-SS-00015 Req't #TitleSummaryVerif. Method 4.8Availability and Reliability Maintain ISOC facilities for the entire mission lifetime with no loss in ISOC capability or performance. A 4.9AutomationAccept autonomous data transfers from the MOC. T 4.10SecurityConnect to the other operations and support centers by an intranet of wide area networks that is closed to, or protected from, public users of the external internet per NASA NPD 2810.1. T Availability, Reliability, Automation, Security

15. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 215 REQUIREMENTS – Level III – LAT-SS-00021 # of Level III 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.1.6 3.1.7 Configuration and Architecture Interface Facilities Redundancy Security Database Website Documentation 60 10 11 6 5 6 4 3.2 3.2.1 3.2.2 3.2.3 3.2.4 Mission Planning & Scheduling Flight Dynamics TDRSS scheduling Target of Opportunity Stored Command Load Generation 62 3 2 8 49

16. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 216 REQUIREMENTS – Level III – LAT-SS-00021 # of Level III 3.3 3.3.1 3.3.2 3.3.3 3.3.4 3.3.5 3.3.6 Telemetry, Command & Data Processing Telemetry Processing Data Processing Data Archiving Alert Telemetry Monitoring User Interface Language Commanding 85 29 19 10 1 22 4 Continued – 2/3

17. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 217 REQUIREMENTS – Level III – LAT-SS-00021 # of Level III 3.4 3.4.1 3.4.2 3.4.3 3.4.4 3.4.5 3.4.6 3.4.7 3.4.8 3.4.9 3.4.10 3.4.11 Monitoring and Analysis Ground System Monitoring Display Pages Sequential Prints Event Messages Memory Mapping & Maintenance Limit Monitoring Configuration Monitoring Trending & Analysis Anomaly Tracking & Notification Timeline Monitoring Calibration & Performance 176 4 38 15 13 7 14 15 32 29 3 6 Continued – 3/3

18. GLAST LAT ProjectISOC CDR, 4 August 2004 Document: LAT-PR-04500Section 218 Summary  Requirements are in the signature cycle –Review and update as needed after GSDR  Development approach tailored to Level III  Ready to develop