1. MRPC Beam Test @ GSI Yongjie Sun University of Science and Technology of China

2. 14th CBM collaboration meeting 2 06 Oct. 2009 Index  Test setup  Preliminary results of 3 prototypes  Summary

3. 14th CBM collaboration meeting 3 06 Oct. 2009 Accelerator

4. 14th CBM collaboration meeting 4 06 Oct. 2009 Setup Our Beam Test Experiment FOPI at Cave B

5. 14th CBM collaboration meeting 5 06 Oct. 2009 6m Setup Proton Beam Pb 2m 42 cm PMT 1,2 PMT 3,4 PMT 5,6 TSU MRPC USTC MRPC Platform x y

6. 14th CBM collaboration meeting 6 06 Oct. 2009 Photo of the setup

7. 14th CBM collaboration meeting 7 06 Oct. 2009 Beam Proton beam, Kinetic energy: 3.5 GeV/c

8. 14th CBM collaboration meeting 8 06 Oct. 2009 DAQ Logic TDCTDC QDCQDC PMT 1-4(5) Discriminator NIM  ECLVULOM, Logic Delay NIM  ECL LMRPC 1-6 (left) 7-12(right) FEE DelayDiscriminatorNIM  ECL Delay Gate Trigger area: 2 cm x 4 cm (without back_scint.) STOP

9. 14th CBM collaboration meeting 9 06 Oct. 2009 Index  Test setup  Preliminary results of 3 prototypes  Summary

10. 14th CBM collaboration meeting 10 06 Oct. 2009 MRPC structure (endview) 5 x 250μm gaps Readout strips HV 2.5cm Readout strips: 2.5 cm x 50 cm HV electrode: Licron spray ~40 M Ω/ □ Made of window glass of 0.7 mm thick

11. 14th CBM collaboration meeting 11 06 Oct. 2009 MRPC #1 (topview) 55 cm 24.1cm 2.5cm 0.6cm Gaps between strips: 0.6 cm

12. 14th CBM collaboration meeting 12 06 Oct. 2009 MRPC #1 +iso-butane 5%+Freon

13. 14th CBM collaboration meeting 13 06 Oct. 2009 ADC 1 ADC 2 ADC 3 ADC 4 ADC 1 ADC 2 ADC 3 ADC 4 PMT calibration ((t 3 +t 4 )-(t 1 +t 2 ))/4 Resolution~67 ps

14. 14th CBM collaboration meeting 14 06 Oct. 2009 T-(t1+t2+t3+t4)/4 ADC ADC MRPC Calibration Intrinsic timing resolution = 67 ps (including momentum spread)

15. 14th CBM collaboration meeting 15 06 Oct. 2009 Efficiency and resolution plateau 65 ps 97%

16. 14th CBM collaboration meeting 16 06 Oct. 2009 Position scan (±7 kV) No significant efficiency drop in the gap Trigger Area: 2 cm wide From both “ charge sharing ” and cross talk.

17. 14th CBM collaboration meeting 17 06 Oct. 2009 Cross Talk Trigger on the strip center: “ Cross talk ” at neighbor strips: 3% Trigger Area: 2 cm wide “ Cross talk ” at next-to- neighbor strips: ~2% Require valid TDC on two ends

18. 14th CBM collaboration meeting 18 06 Oct. 2009 TDC vs. QDC Valid TDCs and valid QDCs (3 sigma above pedestal) Valid TDCs

19. 14th CBM collaboration meeting 19 06 Oct. 2009 MRPC #2 (topview) Top/bottom pcb The readout strips are “ hollowed-out ” alternately. Removed: 5 mm x 4 Left: 1 mm x 5 Removed: 2.5 mm x 9 Left: 0.25 mm x 10

20. 14th CBM collaboration meeting 20 06 Oct. 2009 MRPC #2 Valid TDCs and QDCs

21. 14th CBM collaboration meeting 21 06 Oct. 2009 Efficiency vs. Position Valid TDCs

22. 14th CBM collaboration meeting 22 06 Oct. 2009 Valid TDCs and valid QDCs (3 sigma above pedestal)

23. 14th CBM collaboration meeting 23 06 Oct. 2009 MRPC #3 (topview) 55 cm 24.1cm 2.5cm 0.7cm Gaps between strips: 0.7 cm (upper part) 0.8 cm (lower part) 0.8cm

24. 14th CBM collaboration meeting 24 06 Oct. 2009 MRPC #3

25. 14th CBM collaboration meeting 25 06 Oct. 2009 Efficiency vs. Position Valid TDCs

26. 14th CBM collaboration meeting 26 06 Oct. 2009 Summary  Three prototypes were successfully tested. Efficiency: > 97% Time resolution: 60-70 ps Cross talk: < 3%  With position from silicon detectors, the data will be further analyzed. Thank you!

27. 14th CBM collaboration meeting 27 06 Oct. 2009

28. 14th CBM collaboration meeting 28 06 Oct. 2009 Longitudinal

29. 14th CBM collaboration meeting 29 06 Oct. 2009 Double hit