1. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University A conceptional design of SOLID-TOF Outline: Development of low resistive glass and high rate RPC Experience in MRPC mass production Conceptional design of SOLID-TOF Conclusions 1 Wang Yi Department of Engineering Physics Tsinghua University

2. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 2 Introduction of MRPC Large area, high granularity Good time resolution<100ps High efficiency> 95% Low cost Was used or will be used in ALICE, STAR, FOPI, HADES HARP, CBM, Jlab and NICA- MPD High electric field ~100kV/cm high drift velocity ~220  m/ns high Townsend coefficient Operate in avalanche mode Gas: Freon (electron affinity) iso-butane (UV photon absorption) SF6 (streamer suppressing) Small gap: 0.2-0.3mm, high resolution Multi-gaps: high efficiency

3. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 3 TOF with different rate capability Low rate TOF rate <1kHz/cm 2, such as ALICE, STAR, FOPI, HADES and MPD MRPC with float glass with resistivity ~10 12  cm High rate TOF rate >1kHz/cm 2 ─ CBM ~20kHz/cm 2 in center ─ Jlab ~10kHz/cm 2 ─ Others MRPC with low resistive glass with resistivity ~10 10  cm

4. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 4 World map of MRPC’s rate capability

5. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 55 Performance of low resistivity glass Specifications: Maximal dimension: 50cm×50cm Bulk resistivity: ~10 10 .cm Standard thickness: 0.5mm--2mm Thickness uniformity:  0.02mm Dielectric constant: ~9 Surface roughness: <10nm DC measurement: very stable Thickness distribution Scanned image of glass

6. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 66 Performance test of glass This glass was applied with 1000V for about 32days, integrated charge: 1 C/cm 2 --roughly corresponding to the CBM life- time over 5 years operation at the maximum particle rate.  Resistivity decreases with temperature  Resistivity is very stable in DC measurement

7. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 7 2 cm 13 cm Colloidal graphite: 2M  / Gas gap:10×0.22mm Glass: 0.78mm,1mm resistivity: ～ 10 10 Ω.cm FEE + - Prototype of high rate MRPC (pad-readout)

8. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 888 Cosmic ray test Cosmic ray test: Time resolution: ~80ps Efficiency: >95%

9. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 999 Test results by proton beam @GSI Efficiency and time resolution as a function of high voltage at a rate of about 800Hz/cm 2 When the particle flux increases every 5 kHz/cm 2, the efficiency decreases by 1% and the time resolution deteriorates by 4 ps. In this test, T 0 is about 70ps, the time resolution is deteriorated.

10. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 10 Source: 30MeV electron Trigger: S1^S2^S3^S4^S6^RF Beam size: 7cm 2 MRPC and S6 are placed on movable columns. S6: 35mm*35mm*5mm Reference time: RF signal from ElBE CAEN TDC 1290 N: 24.5 ps/bin QDC: V965: 25 fc/bin Efficiency is determined by the scaler. Gas: 85% Freon+5% Iso+ 10%SF6 Beam Test @Rossendorf

11. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 11 HV scan of pad MRPC Time resolution: 45ps Efficiency: 97 ％

12. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 12 Rate scan of pad MRPC Rate: >30kHz/cm 2 Time resolution: <60ps Efficiency: >90 ％

13. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 13 Time resolution of all pads (1) 605957657362 585462776365 444340506047 423646664851 Time resolution (ps) (T0 is subtracted) Intrinsic time resolution (The jitter of T0, FEE and TD are all subtracted) 10 kHz/cm 2

14. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 14 Time resolution of all pads (2) 7274687179 73 79907881 606254587068 61 68806770 Time resolution (ps) Intrinsic time resolution (ps) 50 kHz/cm 2 Good uniformity

15. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 15 Prototype of high rate MRPC (strip-readout) Colloidal graphite: 2M  / Gas gap: 10×0.25mm Glass: 0.78mm,1mm resistivity: ～ 10 10 Ω.cm

16. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 16 HV scan of strip MRPC (Rosendorf) Working voltage: 6.45 kV Time resolution: 45ps Efficiency: 97 ％

17. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 17 Rate scan of strip MRPC Rate: >30kHz/cm 2 Time resolution: <60ps Efficiency: >90 ％

18. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 18 Position Scan 231 Rpcy -20-10010203040 0 20 40 60 80 100 "or" eff strip1 strip2 strip3 "and" eff Efficiency(%) Rpcy(mm) MRPC#3 MRPC#4

19. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 19

20. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 20 MRPC workshop @ Tsinghua

21. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 21 1/23/45/67/811/12 9/10 1/23/45/67/811/12 9/10 1/23/45/67/8 2006 2007 2008 Prod Start 132 MRPCs 768 MRPCs 1856 MRPCs 2944 MRPCs 4032 MRPCs MRPC production scheme for STAR MRPC production was finished in September of 2008. In Tsinghua: 3100 MRPC have been produced; 2951 Modules passed QA, yield >95% ; 2840 modules shipped to UT Austin. Great success!

22. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 22 PID of STAR-TOF TOF PID capability:  /k ~1.6 GeV/c, ( ,k)/p ~ 3.0 GeV/c Observation of Anti-Helium Nature Vol 473,(2011) 353-356

23. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 23 1/23/4 5/6 7/8 9/1011/121/2 3/4 5/67/8 9/10 11/12 Plan 20112012 Start 20 LMRPCs 40 LMRPCs 60 LMRPCs 80 LMRPCs 100 LMRPCs 115 LMRPCs R&D and production of STAR-MTD

24. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 24 Experimental layout of SoLID

25. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 25

26. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 26 Requirement for TOF  /k separation up to 2.5GeV/c ─ assume 9m path-length: (20:1 kaon rejection at 2.5GeV/c) ─ High rate MRPC ─  <80ps ─ Rate capability>30kHz/cm 2 ─ Estimated rates: 10kHz/cm 2 ─ Active area: 10m 2 ─ Granularity:  A~ 32—63cm 2

27. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 27 TOF Design- MRPC Module Structure of one module Low resistive glass 10×0.25mm gaps 11 strips strip width: 25mm interval: 3mm differential readout This module will be tested with cosmic ray and beam!

28. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 28 TOF structure SM number ： 50 Each SM contain 3 modules Each module consists of 11 strips Strip width ： 25mm Interval ： 3mm Shortest strip ： 13cm Longest strip ： 25cm Total electronic channels ： 3300 Gas box

29. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 29 TOF electronics Fast preamplifier ： Maxim3760 (RICE Univ.) Ninos TOT (ALICE) Padi TOT (GSI) CAD TOT(Tsinghua) QDC (CAEN, 25fC/bin) TDC HPTDC (ALICE, 25ps/ch) GET4 (GSI, 25ps/ch) FPGA TDC (?) DAQ

30. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 30 CAD: Current Amplifier and Discriminator 0is0is V out i th NM0 PM0 i in i ou t 1:N C in M1M2 Current Amp Current Disc. 1.52mm Fully Current Mode  Simple, Compact and Less power consumption

31. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 31 Key parameters CAD-1.0PADI-1NINO-25NINO-13 Peaking time~1ns<1ns1ns0.6ns Linear range 1000  A *1 -60-60  A *1 0-100fC *2 Time jitter<20ps, rms *3 <15ps, rms *4 10-25ps, rms6-25ps, rms Power consumption10mW/ch<30mW/ch30mW/ch5mW/ch Input typeS.E.DIFF. Input impedance 50-70  48-58  30-100  Discriminator threshold 263  A *1 10-400  A *1 20-100fC *2 CMOS process 0.35  m0.18  m0.25  m0.13  m *1: for current pulse with 0.3ns rise time, 1-2ns FWHM, and 0.3ns fall time *2: for square current pulse with 200ps width *3: for 200  A input current *4: for 100  A input current

32. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 32 A solution for TOF system CAD ASIC FPGA TDC FEE Board Digitizer Board IN+ IN- DAQ Board Ethernet MRPC MRPC technology will be used to construct TOF. Combine ASIC FEE and FPGA TDC and Ethernet DAQ s

33. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 33 Conclusions Development of low resistive glass with resistivity ~ 10 10 Ωcm, very good performance. Development of pad- and strip- readout high rate MRPCs, rate capability>25kHz/cm 2, time resolution<60ps. The glass and detector is adopted by CBM to construct TOF. Conceptional design of SOLID-TOF. It can also be use in other experiments such as NICA- MPD.

34. Third workshop on hadron physics in ChinaWang Yi, Tsinghua University 34 Thanks for your attention!