1. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 1/13 SVAC Data Taking during LAT Integration @ SLAC Oct 4, 2004 Eduardo do Couto e Silva SLAC eduardo@slac.stanford.edu 650-926-2698 Gamma-ray Large Area Space Telescope

2. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 2/13 SVAC Data Runs during LAT Integration @ SLAC All this information will be included in – “SVAC Plan for LAT Integration – LAT-MD-00575” The SVAC data taking consists of cosmic rays and VG data for –Low level instrument characterization (performance) –Calibrations We optimized the data taking time during Integration –Calibration and characterization use the same data Data is taken with the hardware in the following configurations –Partially populated LAT (see next slide) –Full LAT in vertical orientation –Full LAT in horizontal orientation This is the configuration @ NRL during environmental tests

3. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 3/13 Partially Populated LAT – Cosmic Rays TWO DAYS OF DATA TAKING FOR EACH CONFIGURATION Day 1: 24 hours or less (TBD) for charge injection and/or support calibrations –To provide input to calibrations with cosmic rays –To be divided between TKR and CAL Day 2: 24 hours of cosmic rays at nominal settings for each configuration –low level instrument characterization –Calibrations with cosmic rays

4. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 4/13 Partially Populated LAT - SVAC Data: Day 1 TKR Calibrations (max 12 hours, preferably 8 to stay within 1 shift) –Electronic calibrations of TOT/GTFE (4-5 hours) –Other electronic calibrations (~ 4 hours) CAL Calibrations (max 12 hours, preferably 8 to stay within 1 shift) –Electronic calibrations for each GCFE (2 hours) –FLE/FHE scans with muons (~ 2 hours) –Muon data taking –(4 hours) –TKR: trigger enabled –FLE: ~ 100 MeV but disabled –FHE: ~ 1 GeV enabled Flight settings –LE rails: ~ 1.6 GeV –HE rails: ~ 100 GeV Auto Range: one range readout –Zero-suppression: enabled –LAC threshold ~ 1 MeV –CAL TACKdelay 70 (TBR)

5. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 5/13 Partially Populated LAT - SVAC Data: Day 2 1 hour of CAL pedestals with Zero suppression OFF 23 hours of cosmic ray data taking with the following settings TKR nominal settings –Flight Configuration –TKR trigger enabled –TKR delay 0 (TBR) –TKR hit threshold (0.25 MIP) CAL Nominal Settings –Flight Configuration –TKR: trigger enabled –FLE: ~ 100 MeV but disabled –FHE: ~ 1 GeV, enabled –CAL TACKdelay 70 (TBR) –Muon Gain: –LE rails: ~1.6 GeV –HE rails: ~4 GeV –Intermediate Data Volume: –Auto-range, four-range readout –Zero-suppression: enabled –LAC threshold ~ 1 MeV

6. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 6/13 SVAC Data Taking after LAT assembly (1) 15 days (24 h/day) at vertical orientation –10 days – Best GND calibration sample –TKR nominal settings –CAL HE muon gain: (zero suppression ON, LAC: 1 MeV, autorange, four range readout) –ACD nominal settings (Zero Suppression OFF, disable veto) –2 days – zero suppression data with full LAT –TKR nominal settings –CAL HE muon gain: (zero suppression OFF, autorange, four range readout) –ACD nominal settings (Zero Suppression OFF, disable veto) –2 days – test as you fly (TKR and CAL only) –TKR nominal settings –CAL Flight gains: (zero suppression ON, LAC: 1 MeV, autorange, one range readout) –ACD nominal settings (Zero Suppression ON, disable veto) JJ recommends zero suppression off if we can afford it

7. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 7/13 SVAC Data Taking after LAT assembly (2) 1 day (24 h/day) at vertical orientation - ACD Calibrations –6 hours – ROI 1: All ACD sides enabled –ACD nominal settings (Zero Suppression OFF, enable trigger) –TKR nominal settings and trigger disabled –CAL nominal settings and trigger disabled –6 hours – ROI 2: S1 && S2 –ACD nominal settings (Zero Suppression OFF, enable trigger) –TKR nominal settings and trigger disabled –CAL nominal settings and trigger disabled –6 hours – ROI 3: S3 && S4 –ACD nominal settings (Zero Suppression OFF, enable trigger) –TKR nominal settings and trigger disabled –CAL nominal settings and trigger disabled –6 hours – ROI 4: Top && ( S1 || S2 || S3 || S4) –ACD nominal settings (Zero Suppression OFF, enable trigger) –TKR nominal settings and trigger disabled –CAL nominal settings and trigger disabled JJ recommends to OR all conditions or use ROI 1 only (depends on what the ACD noise rate is)

8. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 8/13 SVAC Data Taking – VG For each configuration 1 DAY OF DATA TAKING (16 h/day) 3 hours of cosmic rays –Used as a control sample for background subtraction –Nominal settings with hardware oriented horizontally –TKR trigger –ACD nominal settings, zero suppression ON, disable veto –CAL: high muon gain, one range readout. 13 hours VG at nominal settings for each configuration –low level instrument characterization –Nominal settings with hardware oriented horizontally –TKR trigger –ACD nominal settings, zero suppression ON, disable veto –CAL: high muon gain, one range readout.

9. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 9/13 Can We Handle the Data Volume? ACD –(89 tiles + 9 ribbons) x 2 PMTs = 194 signals –Zero suppression OFF = 194 –Zero suppression ON = 5 –We neglect noise occupancy for this calculation »All numbers should be multiplied by ~ 2 to get the results in bytes CAL –8 layers x 12 crystals x 2 ends x 16 towers = 3072 signals –Zero suppression OFF and 4 range = 4 x 3072 = 12238 –Zero suppression ON (~2 crystals hit/layer in single tower) = 32 –Zero suppression ON and 4 range = 4 x 32 = 128 –We neglect noise occupancy for this calculation »All numbers should be multiplied by ~ 2 to get the results in bytes TKR –1536 strips x 36 layers x 16 towers x 10 -4 occupancy = ~100 signals »Number above should be multiplied by ~ 2 to get the results in bytes

10. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 10/13 Data Volume during LAT Integration 1 Tower –TKR ~ 200 –CAL ~ 256 –~460 x 25 Hz x 86400 s x 1 days = 0.01 TBytes 2 Towers~ 0.02 TBytes 4 Towers~ 0.04 TBytes 6 Towers ~ 0.06 TBytes 8 Towers~ 0.08 TBytes 10 Towers~ 0.10 TBytes 12 Towers~ 0.12 TBytes 14 Towers~ 0.14 TBytes 16 Towers ~ 0.16 TBytes –Estimates were obtained by multiplying the rate by number of towers available to trigger Total ~ 0.72 TBytes

11. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 11/13 Data Volume: LAT - “Long runs” (1) 2 weeks (24 h/day) at vertical orientation –10 days – Best GND calibration sample –TKR ~ 200 –CAL ~ 256 –ACD ~ 388 »~844 x 300 Hz x 86400 s x 10 days = 0.218 Tbytes –2 days – zero suppression data with full LAT –TKR ~ 200 –CAL ~ 25576 –ACD ~ 388 »~26000 x 300 Hz x 86400 s x 2 days = 1.347 Tbytes –2 days – test as you fly (TKR and CAL only) –TKR ~ 200 –CAL ~ 64 –ACD ~ 388 »~652 x 300 Hz x 86400 s x 2 days = 0.034 Tbytes

12. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 12/13 Data Volume LAT - “Long runs” (2) 1 day (24 h/day) at vertical orientation – ACD Calibrations – Baseline GND calibration configuration for CAL and TKR –TKR ~ 200 –CAL ~ 256 –ACD ~ 388 »~844 x 200 Hz x 86400 s x 1 days = 0.014 Tbytes 1 week (24 h/day) at horizontal orientation –7 days – Baseline GND calibration prior to NRL –TKR ~ 200 –CAL ~ 256 –ACD ~ 388 »~844 x 200 Hz x 86400 s x 7 days = 0.101 Tbytes

13. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 13/13 SVAC runs: Data Volume during I&T at SLAC SVAC Day 1 (during I&T)09 days0.18 Tbytes SVAC Day 2 (during I&T)09 days0.72 Tbytes Long Runs Vertical: Muon Gain 10 days0.22 Tbytes Long Runs Vertical: Zero Sup.02 days1.35 Tbytes Long Runs Vertical: Flight Config02 days0.03 Tbytes Long Runs Vertical: ACD Calib01 days0.01 Tbytes Long Runs Horizontal 07 days0.10 Tbytes E2E tests (see Gary’s list)05 days0.10 Tbytes VG data taking (TBD)03 days0.05 Tbytes Total of raw LDF data ~ 3 Tbytes »The number above was rounded up Total after offline processing (x 2.5)~ 7.5 Tbytes If ACD zero suppression is ON we reduce raw data volume by ~ 0.3 Tbytes About 4000 raw files of ~ 500 MB size to search and analyze so we depend strongly on the elog database for searching runs. No reprocessing is assumed !

14. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 14/13 Questions to be addressed Need similar data volume estimation ASAP for all other tests if I&T wants to ask SAS to provide support. Otherwise I&T should work out how to get more disks on it own. Does the volume of non zero suppressed data poses a challenge for data transfer? DMZ and local storage in Clean room PC Can the network and/or LATTE handle data throughput? –It gets worse with the E2E high trigger rate tests Are there changes expected when we have FSW available? –Calibration scripts and commanding –Data reduction –Retrieval of register configuration information –Data taking Time –Does the runs database(elog) need to be modified?

15. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 15/13 Back up slides from Gary for E2E Test using particle sources

16. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 16/13 Event Sizes Zero Supp (=Nominal Trigger Message)~250 bytes Zero Supp, All 4 ranges ~450 No Zero Supp ~6,400 No Zero Supp, All 4 ranges ~25,000 Max to SIIS (Space Craft Instr Interface Sys) ~ 5 Mbytes/sec High Rate, No Zero Supp = 10 K events/sec x 6.4 Kbytes/event = 64 Mbytes/sec Prescale the trigger? – No, want to exercise the electronics ! Software Filter (in DAQ) ?– Yes 1) to get below 5 Mbytes/sec 2) to get below ~150 Kbytes/sec so 1 hr file <500 Mbytes

17. GLAST LAT Project SE Test Planning meeting October 4, 2004 E. do Couto e Silva 17/13 E2E Data Volume Software Filter (TBD) keep 1 hour run File Sizes < 500 Mbytes –Prescales Ext Trigs before writing to disk –Prescales all Trigs in non-zero supp data –Prescales all Trigs for high rate Cal Trigs, Am 241 data E2E Particle Data volume generated at SLAC by I+T –Individual Tests 87 runs x.5 Gb ~ 44 Gbytes –Daily Trending 30 days x 1 hr x.5 Gb ~ 15 Gb –Monthly Long Run 1 month x 24 hr x.5 Gb ~ 12 Gb E2E Data volume generated at Thermal Vac by I+T –~1/2 x Individual Tests ~ 22 Gb Total data volume = 100 – 1000 Gb (depends on software filtering decisions)