GLAST Large Area Telescope: Gamma-ray Large Area Space Telescope GLAST Large Area Telescope: Instrument Science Operations Center CDR Section 4.2 Operations Scenarios Lori Bator ONE-SLAC lbator@slac.stanford.edu 650-926-5352

Topics LAT Operation Phases Description of LAT Operations Monitoring Requirements L&EO Support Anomaly Resolution Process Status

LAT Operations Phases LAT I&T Pre-FSW (EM) Post-FSW (Flight unit level) Observatory I&T NRL Spectrum Launch and Early Orbit (L&EO) – Phase 0 LAT power-on and configuration Initial checkout First year – Phase 1 Survey mode Second and subsequent years – Phase 2 Pointed observation

Pre-launch Testing LAT I&T Phase Tests Goal: Verify and validate development of ISOC tools and functions on testbed and through software simulation Data Challenges Goal: “End to end” test of science analysis software Ground Readiness Tests (GRTs) Goal: Verify and validate system interfaces and data flows Observatory I&T Phase Tests Goal: Verify and validate ISOC capabilities End-to-End (ETE) tests Goal: Verify and validate interface between ground system and observatory Mission Simulations Goal: Verify operation team readiness prior to launch

Initial Turn-On and Checkout (Phase 0) Turn-on (power-up) procedure will not be executed automatically Humans required to check environmental conditions prior to significant steps Must establish correct LAT configuration to ensure communications Functional checkout of ACD, CAL and TKR Perform initial calibrations Special requirements ACD will have control of triggering; therefore no science data taking available for ~ 3 days Phototube high voltages need to be turned on one at a time and monitored

Science Operations (Phases 1 and 2) Data taking Daily On the order of a few commands to initiate Calibration Weekly, biweekly and monthly Load changes to tables and FSW Infrequent On the order of a few commands and/or file uploads which may be large Load new tables and files Diagnostics SAA management FSW turns down high voltage automatically based on SAA message from S/C

Monitoring Requirements LAT FSW monitors parameters onboard and will take action (power-off or stop activity) in response to limit violations S/C monitors some temperatures and will power off LAT if needed MOC monitors HK data for limit violations No critical monitoring or actions required ISOC will define limits in LAT T&C database ISOC will provide and direct use of any contingency procedures ISOC monitors HK and Science data for limit violations and trends Respond to degradation, noise, changes in performance, and failure by uploading commands or files to change configuration No critical monitoring except during power-up Monitor ACD temperatures when switching between pointed and survey modes

Limits Yellow Monitored point is outside the designed or acceptance tested range but still within the qualification tested range Operator monitors data and notifies responsible engineer in a timely manner Red Monitored point is operating outside the qualification tested range FSW or S/C initiates immediate action Operator initiates contingency procedure (if called for) and immediately notifies responsible engineer

T&C Database Delivery Process LAT T&C database is initially provided to Spectrum CDRL delivery prior to LAT ship to Spectrum ITOS format Updates Provided by ISOC to Spectrum until L+60 days After L+60 days, updates are provided by ISOC to MOC Format and method of notification and delivery are defined in Operations Data Products ICD (492-MOC-009)

Anomaly Response Process

L&EO Support Estimate 9 Persons for L&EO Support 1 CAL seat 1 TKR seat 1 ACD seat 1 I&T seat 1 OPS seat 1 FSW/DAQ seat 1 SYS/Thermal/Mech seat 1 Mgmt/Science/contingency lead 1 optional seat  Support area and infrastructure on same scale as Spectrum has requested

Status ISOC operations concept documented in LAT-SS-01378 ISOC Operations Plan Detail on operations will evolve from FSW development and I&T tests Detail will be captured in Operations Handbook (ECD Oct 2005) and Operations Procedures (ECD L-6 months) Command sequences Constraints Contingency actions