GLD-CAL and MPPC

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-Calorimeterdetector model • Scintillator strip CAL. • flexible in length (WLS Fiber R/O) • effective segmentation 1 x 1 cm2 • small photon sensor 1cm

5. GLD-Calorimeterglobal 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 28X0 • HCAL : R = 2.3 ~ 3.5 m (1.2m) : • 26 mm/layer ( 20 + 5 + 1)mm • 46 layers  5.5 lint

7. GLD-CAL layer ECAL HCAL

8. GLD-CAL layer HCAL cross ECAL cross

9. GLD-CAL parameters

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

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

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

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 to verify this idea and PFA R&D needed for R/O electronics of MPPC

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 1.6mmf 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. 199ms train 1ms 377ns (150?) 2820b (5600?) 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 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. LED WLS fibers SiPMs Fiber to PMT 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

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. 40kΩ ASIC 8-bit DAC 0-5V 100MΩ 0.1pF 2.4pF 0.2pF 1.2pF 0.4pF 0.6pF 0.8pF in 0.3pF 12kΩ 4kΩ 24pF 10kΩ 50Ω 10pF 12pF 6pF 8pF 4pF 2pF 1pF 100nF 3pF Variable Gain Charge Preamplifier Variable Shaper CR-RC² 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 Photon sensor Ethernet controller By M. Tanaka (KEK)

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