1. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Status of PRS/SPD detector Cosmic test results Installation/tuning of monitoring system Status of PMT calibration Radiation Source with magnet separator Planning

2. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Cosmic test results Load2 SPD#7(O “A”), SPD#8(O “A”), SPD#4(I “A”), PS#4(I “C”) – OK (+check data) Load 3 – PS#1,#2,#3; SPD#3 OK ; data checked Load 4 – PS#7,#8; SPD#1,#2 OK ; data checked Load 5 – PS#5,#6; SPD#5,#6 – PMT calibration done, problem with one(?) pixel on PMT#2 (over illuminated with LED). Analysis in progress.

3. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Cosmic test results Load2 OK: –SPD#8 (outer “A”) – check data for errors –SPD#7 (outer “A”) - check –SPD#4 (inner “C”) - check –PS#4 (inner “C”) - OK

4. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Cosmic results

5. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Cosmic results

6. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Status of monitoring system Monitoring system is installed on all 16 SMs. LED drivers are tuned with oscilloscope on 15 SMs. Scope of work done: –installation done for 750 drivers +120 splitters, –Constructed and installed ~1000 fixations, 900 cables –40,000 tunings (3 iterations for channel) is done –Found ~ 1000 badly soldered elements, mostly trimmers –+ bad contacts, shorts in connectors Measurements using cosmic test DAQ show that –Slope of light vs bias voltage of LEDs is rather different. –Tuning with oscilloscope is done at high signal ~ 100 MIPs and often works badly for low signals ~ 5 MIP. –retuning at low signal improves situation. –Checking with DAQ also help to detect electrical cross-talk between drivers (bad contacts in connectors, soldering and grounding) 4 PS ‘C’ site are checked and fine tuned using CT DAQ and ready for transportation Check and tuning with CT DAQ is relatively fast and very useful.

7. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting LED stability scan (violet LEDs) Start 27/04 21:00 End 28/04 9:00 No temperature monitor

8. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Stability scan - 1, 12 hours, night Blue LEDs (WUSTLICH) Start at 21:00 21/04, end 9:00 22/04 Channel #10: bad soldering at the driver output, LED got disconnected -> gives an idea of effect on other channels.

9. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Stability scan -2, 12 hours, night The same time, another driver. Ambient temperature was not monitored.

10. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting LED amplitude scan -1 Violet LEDs: Signal from 64 LEDs was measured by Lecroy QDC (Y-axis channels) as function of bias voltage 2.6- 2.85V. 1000ADC c ~ 550 ph.el. ~ 20-30 MIPs

11. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting LED amplitude scan -2 Example of 64 Blue LEDs scan over 2.8- 3.4V is shown on the plot Some of LEDs have different slope of the characteristics

12. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting PMT calibration. Comparison with Clermont data. Finally, after correction the data for the difference in pixel mapping and gain coefficient definition, the comparison of PMT calibration without mask vs calibration of Clermont (Stephane) shows quite reasonable coincidence for three from four tubes.

13. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting PMT calibration. Comparison with CF data. Three of four tubes are correctly identified. For these 3 tubes the ratio of calibration coefficients does not walk out of +-20% corridor. RMS of the ratio for 3 identified tubes is 9, 9.5 and 7.5%. RMS for the ratio of very different tubes (plot left-up) is 18% (corridor is +-33%).

14. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting PMT calibration PMT calibration with mask is needed for beter understanding of data First calibration with mask with 1 mm holes was done yesterday Analysis is in progress

15. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Radiation source with magnetic separator and trigger Sr90 370MBq El. magnet Trigger counterSeparator exit through collimating slit

16. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Rad. Source with scintillator pad Signal from rad.source was measured as a function of magnet current. On the plots the spectrum of signal is shown. Optimal values of current are found 0.8-1.05A. The relative width ~15% of spectrum is dominated with photostatistical fluctuations Trigger rate obtained was 200- 400 Hz with fake trigger contamination ~1%. Source efficiency with large scintillator pad was achieved as 50-60%.

17. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Rad.source studies (scintillator vs LSO crystal) Photo-statistics: Signal from scintillator pad was measured from both ends of fibre ~20-25 ph.el./end To measure the signal with larger light output we used 1 cm^3 LSO crystal with PMT read-out. Resolution “in peak” obtained was ~8-9% (r.m.s). “Peak” is ~1/3 of triggers on large low energy substrate (due to crystal geometry?)

18. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Rad.source studies (“dead” material) Dead material in front of pad: 2 mm of fiberglass ~ module box’s bottom. Signal losses are: 1.Energy losses are ~50%; 2.Trigger rate ‘in peak’ drops ~3-4 times. Conclusion: rad.source with magnetic separator + trigger provide reasonable signal and rate conditions. Final check should be done with real module.

19. E.Guschin (INR,Moscow) 3 May 2006Calorimeter commissioning meeting Planning 1.To prepare SPD SMs of site “C” for transportation – next week add. (re)measurement/replacement of 1 module Monitoring system check/retuning with DAQ 2.Analysis of PMT calibration for the last setup – this week 3.Preparation of the rest of super-modules site ”A” for transportation – end of May