1. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 1 Gamma-ray Large Area Space Telescope 7D: Tray test plans GLAST Large Area Telescope: GLAST Large Area Telescope: Tracker Subsystem Nicola Mazziotta University and INFN Bari - Italy mazziotta@ba.infn.it

2. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 2 Outline  Overview  Tray test matrix  Panel vib plan  Tray thermal plan  Test schedule  Stacked cosmic rays Reference LAT Documents: 1.LAT-MD-00408, LAT Instrument Performance Verification Plan 2.LAT-SS-00788, LAT Environmental Specification 3.LAT-TD-01005, Thermal Test Results on Thick Converter Mock-up Trays 4.LAT-TD-01249, Thermal Test Results for Pre-Engineering Model Trays 5.LAT-PS-01584, LAT Tracker Tray SSD Ladder Panel Assembly Procedure 6.LAT-TD-00154, Tray Vibration Test Plan 7.LAT-TD-01839, Tray Thermal Test Plan

3. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 3 Tray test matrix ItemQuantityQuantity to testHigh freq sine SweepRandom VibeStacked cosmic raysFunctionalThermal CycleTest site Lot A Panels 19 Z axisQual Z axis Italy factory Lot A Trays 19 QualINFN Perugia (in Terni) (thermal) Lot B & Flight panels 323 + spares Z axisAcc Z axis Italy factory Lot B & Flight trays 323 + spares AccINFN Perugia, Bari, Pisa, RomaII

4. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 4 Overview Tray factory (panels)Vibration test*Ladder factory Tray assembly: ladders and MCMs on trays Tray thermal cycles*Stacked cosmic rays*Electrical testTray functional test*Tower assembly *Environmental tests Electrical test before MCMs encapsulation

5. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 5 Panel vib levels Frequency (Hz) ASD Qual Level (g 2 /Hz) ASD Accept Level (g 2 /Hz) 200.0260.013 20-50+6 dB/oct 50-8000.160.08 800-2000-6 dB/oct 20000.0260.013 Overall14.0 g rms 10.0 g rms Duration2 min1 min Random vibration Frequency (Hz) ASD WN Level(g 2 /Hz) Overall g rms Duration (min) 20 ÷ 200010 -4 0.451 White Noise Frequency range 20  2000 Hz Sweep rate2 oct/min Target Amplitude 0.5 g 0-pk Sine sweep

6. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 6 Panel vib set up Accelerometers: Control: two mono-axial accelerometers positioned on two of the four L-shaped block TP1&TP2 Fixture: three mono axial accelerometers placed on a corner on one of the four L- shaped block TP6 Tray: one three-axial accelerometers in the middle of panel TP5 Centrotecnica set up: - 1 LDS shake table - 2 fixtures - 9 read out channels - 4 tested trays/day rate × W side on the top

7. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 7 Panel vib sequence thrust axis StepDescriptionTestLevel 1 Fixture, tray and accelerometers mounting 2 Fixture calibration and tray resonance search Sine sweep0.5 g 0-pk 3Random vibration Qual (Lot A) Acc (Lot B & Flight) 4Normal mode checkSine sweep0.5 g 0-pk 5Dismounting 6Test completion

8. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 8 Tray thermal levels AcceptanceQualification/Survival Temperature Range-20°C  35°C-30°C  50°C # of cycles44 Temperature rate20°C/hr Pressure1 atm T-C Duration @ T extreme5 hr Total Duration62 + 2 hr72 + 2 hr On orbit temperature range -15°C  30°C

9. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 9 Tray thermal sequence StepDescription Level 0Functional test 1Thermocouple set up 2Chamber set up 3Thermal cycles Lot A Qual Lot B&Flight Acc 4Dismounting 5Functional test 6Test completion The tray will be tested in its own service box.

10. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 10 Test schedule Vib test rate ≥ 4 panels/day (Centrotecnica-Milano) Thermal test lot ≥ 4 trays/cycle in 4 climatic chambers (2 ready by Pg in Terni, 1 foreseen in Pi, 1 foreseen in Ba) Test rate/climatic chamber ∼ 1 tower/month

11. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 11 Cosmic rays test Cosmic rays test Tray stacked in single view 2 stacks for a whole tower, readout with a single TEM

12. GLAST LAT ProjectPeer Review, March 24-25, 2003 7D 12 Conclusions The thermal and vibe tests on trays are well understood The vibe test rate in Centrotecnica is adequate The thermal test rate with the Perugia equipment in Terni is just sufficient, but the test lines will be doubled The mechanics to perform cosmic rays tests is under construction. The flux allows a test in realistic time. The mini-tower experience will be the ground base to define the cosmic rays test.