1. GLD-CAL and MPPC Based on talks by T. Takeshita and H. Matsunaga @Snowmass2005 K. Kawagoe / Kobe-U 2005-Sep-16 MPPC mini-workshop @Kyoto-U

2. GLD “concept” To identify and measure particles in jets The largest detector concept for ILC Large super conducting magnet ECAL/HCAL inside coil (3.5m radius) Large TPC (Tracker : 2m radius)

3. GLD-Calorimeter far from IP ~ separate particles in a jet minimum geometrical overlap 1 cm granularity : PFA Large cost = number of channels flexibility in the component size reliability in large area small dead space

4. GLD-Calorimeter detector model Scintillator strip CAL. flexible in length (WLS Fiber R/O) effective segmentation 1 x 1 cm 2 small photon sensor 1cm

5. GLD-Calorimeter global design

6. GDL-CAL layers at 90deg. ECAL : R = 2.1 ~ 2.3 m (0.2m) : 6 mm/layer ( 3 + 2 + 1)mm 33 layers  28X 0 HCAL : R = 2.3 ~ 3.5 m (1.2m) : 26 mm/layer ( 20 + 5 + 1)mm 46 layers  5.5 int

7. GLD-CAL layer ECALHCAL

8. GLD-CAL layer HCAL cross ECAL cross

9. GLD-CAL parameters absorber active material Layers barrel/ec strip length N. R/O ECAL W 3mm scintillator 2mm 33/ 33 4cm? ~6M ch HCAL Pb 20mm scintillator 5mm 46/ 48 20cm? ~30M ch

10. GLD-CAL R/D’s ECAL test with MAPMT

11. GLD-CAL R/D’s cont’d A typical event L1 L2 L3 L4 L5 L6 Integrated lateral shower profile

12. GLD-photon sensor MPPC R/D laser beam spot single photon eq. MPPC100

13. GLD-CAL R&D’s cont’d Photon sensor R&D MPPC of Hamamatsu 100 pixels 1,2,3,4,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,60 pixels GM at each pixel

14. GLD-CAL R&D’s cont’d Beam Test at Fermilab 2007 R&D needed for R/O electronics of MPPC to verify this idea and PFA

15. GLD-CAL collaborators Kyongpook (D.Kim) : Scintillator JINR (P.Evtoukhovitch): SiPM Kobe (K.Kawagoe) : MPPC Niigata (H.Miyata) : MPPC pixel Tsukuba (S.H.Kim, H.Matsunaga) : Sim. KEK (A.Miyamoto, K.Fujii) : Sim. Shinshu (T.Takeshita) : BT

16. GLD-CAL Open issues for ECAL strip is sufficient enough for fine segmentation? <> PFA results which optimize the length of a strip options real 1cm x 1cm or smaller cell if problem in photon finding

17. GLD-CAL Open issues for HCAL again strip length for hadronic interactions (neutral hadron) PFA studies neutron hits >>> delayed hits electronics timing

18. GLD-HCAL a pion event digitized hits

19. GLD-CAL engineering issues support for HCAL by coil support for ECAL by HCAL cabling installation

20. Summary:GLD-CAL largest calorimeter fine segmented & optimized for PFA scintillator strip based technique is proved photon sensor R&D electronics R&D detailed design

21. Requirements for MPPC To get 10 photons for MIP per ECAL strip (2mm- thick) – PDE ~ 50% – Effective area suitable for 1.6mm  fiber Gain = 10^6 or more (no amplification needed) Dynamic range for ECAL – At least 50xMIP signal (=500photons) => Number of pixels > 1000 – More number of pixels is desired… Good timing resolution for – Bunch ID (trivial?) – Detection/removal of slow neutron component – TOF at the innermost ECAL layer ?

22. Requirements for Readout Readout between bunch trains (199ms) –Assuming 1Gbit/sec transfer rate, ~25 Mbytes at maximum 4 bytes/event x ~6k events/train is possible –Zero suppression –Buffers 199ms 1ms1ms 377ns (150?) 2820b (5600?) train Bunch structure

23. Requirements for Readout (cont’d) Number of pixels: ~1000 -> 10~12 bit dynamic range Good timing resolution –Bunch ID –Slow neutron detection? –TOF at the innermost layer of ECAL ? Dark hit-rate: < 1MHz tolerable ? Low power consumption: –~20mW/ch may be possible –Power loss in cable should be small

24. Some issues on sensors Operational voltage range is narrow –~0.1 V for MPC Accurate bias voltage control (and also modest temperature control) is necessary Power supply is also the key issue Probably, operational voltage of MPC varies from device to device –How to know the best voltage for huge number of devices ? –How to provide various bias voltages to them ?

25. Solution by CALICE group Talk by Felix Sefkow (DESY) in Calorimeter session This is just for testbeam; may need better method for production –Number of sensors: a few thousands –SiPMs with ~1000 pixels –During testbeam, they will be monitoring sensor gain with LED, without temperature control

26. Bias voltage adjustment Bias voltages are determined at test bench in advance for all sensors –15 SiPMs under monitored LED source –Adjust working point (bias voltage) to 15 pixels/MIP –Up to 500 / week LED Fiber to PMT SiPMs WLS fibers

27. Voltage variation Two clusters for bias voltage setting: –33~41V, 60~67V Sensors are grouped in modules according to bias voltage –108 / half module –+- 2V / module

28. Front-end Electronics ILC-SiPM chip: 18ch Pre-amplifier, shaper, track and hold, mux –based on CALICE SiW ECAL chip SiPM bias adjustment ASIC

29. Our plan ECAL beamtest: ~2007 (FNAL / DESY) ? –Front-end electronics and DAQ DAQ system might be shared with other groups? –Mass production and quality control Beyond testbeam –??? Manpower: –Manobu Tanaka (KEK) : ASIC development –Patrick LeDu is interested … –Others?

30. Basic idea of FE board SQV: Synchronous Current Integrator for Q-to-V conversion By M. Tanaka (KEK) Photon sensor Ethernet controller

31. SQV-TEG & Ethernet board Prototype boards already exist Bias voltage controller should be added