1. ILC Detector Design Study in Japan Contents Introduction Overview of ILC detector R&D Requirements for ILC detectors Activities in Japan Detector concept study Sub-detector R&D GLD Detector Outline Document Summary Yasuhiro Sugimoto KEK

2. Introduction Overview of “Detector R&D” for ILC Requirements for ILC Detectors

3. Milestones of ILC (Construction) Technology Choice Acc. 2004200520062007200820092010 BCDRDR Start Global Lab. Det. DODsDCRLOIs (?) Sub-det. R&D Done! TDR Done! Almost done! GDE WWS GDE: Global Design Effort WWS: World Wide Study of physics and detector BCD: Baseline Configuration Document RDR: Reference Design Report DOD: Detector Outline Document DCR: Detector Concept Report Priority-1 itemsPriority-2 items Only 3 years left for critical R&Ds cooperation Conceptual design

4. Detector Design Study Detector Concept Study Conceptual design study of detector systems 3 major concepts + 1 new concept Sub-detector R&D More than 60 groups in the world Usually related with several detector concepts  Horizontal collaboration SiD LDC GLD4 th

5. Requirements for ILC Detectors Physics goal of ILC Wide variety of processes Energy range: M z <E CM <1 TeV Basic requirements Reconstruct events at fundamental particle (quark, lepton, gauge bosons) level Efficient identification and precise 4-momentum measurement of these fundamental particles ILC detectors should have performances of Good jet energy resolution to separate W and Z Efficient jet-flavor identification capability Excellent charged-particle momentum resolution Hermetic coverage to veto 2-photon background

6. Performance Goal Jet energy resolution  1/2 w.r.t. LHC Impact parameter resolution for flavor tag  1/2 resolution term, 1/7 M.S. term w.r.t. LHC Transverse momentum resolution for charged particles  1/10 momentum resolution w.r.t. LHC Hermeticity

7. Advantage of high performance detector Example: Strongly interacting Higgs Projection to M 1 =M 2 M 1 qq(GeV) M 2 qq(GeV)

8. Advantage of high performance detector Example: Higgs muon pair decay Br(H   +  - )~3x10 -4 O(10) events with L=500 fb -1 The peak above background may be seen with excellent tracker 

9. Activities in Japan Detector Concept Study GLD (SiD) Sub-detector R&D Vertex detector TPC Calorimeter (Si tracker for SiD) GLD Detector Outline Document

10. Detector Concept Study GLD – a large gaseous detector Large radius calorimeter to optimize for PFA Large radius gaseous tracker (TPC) to get excellent momentum resolution and pattern recognition capability Forward calorimeter down to ~5 mrad Precision Si micro-vertex detector Si inner-, forward-, and endcap tracker Muon detector interleaved with iron return yoke Moderate solenoid magnetic field of 3 T

11. GLD Vertex detector and Si inner and forward tracker are not shown z-r view r-  view

12. PFA PFA (Particle Flow Analysis) is thought to be a way to get best jet- energy resolution Measure energy of each particle separately Charged particle : by tracker Gamma : by EM Calorimeter Neutral hadron : by EM and Hadron Calorimeter Overlap of charged cluster and neutral cluster in the calorimeter affects the jet-energy resolution Cluster separation in the calorimeter is important Large Radius (R) Strong B-field Fine 3-D granularity (  ) Small Moliere length (R M ) Algorithm Often quoted figure of merit :

13. Simulation Studies for GLD Study of PFA (Tohoku, Niigata, KEK, Tsukuba, Tokyo, Shinshuu, Kobe, Mindanao) Tracking performance (Tsukuba, KEK, Korea, Kyungpook, Yonsei) Impact parameter resolution (Tohoku, Tsukuba, KEK) Vertex charge determination (Oxford, RAL) Background study (Saga, Tokyo, KEK) Design study of solenoid magnet and return yoke based on FEA (KEK)

14. Simulation Study Study of “cheated PFA” Perfect track-calorimeter matching based on Monte Carlo truth Shower fluctuation, particle interactions with material fully simulated  Identify terms contributing to the resolution to design the best detector u,d,s quark pair Events at Z pole

15. Simulation Study Source of resolution in “cheated PFA” Neutrino0.30 GeV 5 mrad cut0.62 Low Pt track0.83 TPC res.0 EM Cal res.1.36 HD Cal res.1.70 Total2.48 (require TPC) Contribution from low p t cut is significant. Low p t tracking using only VTX and SIT will be studied.

16. Simulation Study Realistic PFA CAL energy sumPFA Z → qq @ 91.18GeV More effort / new idea is necessary to achieve the goal of 30%/SQRT(E)

17. Simulation Study Tracking performance The performance goal can be achieved with GLD detector with TPC of 150  m point resolution

18. Future plan for concept study By the end of 2006 (by DCR) More detailed detector simulation More realistic detector design More precise cost estimate Towards LOI Continue the activity listed above and update the design based on the outputs of sub-detector R&D Formation of an experimental group

19. Sub-detector R&D: VTX KEK, Tohoku, Tohoku-gakuin, Niigata collaboration Challenges of ILC vertex detector (VTX) Very thin wafer ( < 100  m/layer) and excellent point resolution ( < 3  m) are necessary to achieve the performance goal In order to keep pixel occupancy due to beam background hits reasonably low, the sensors have to be read out 20 times/train and very fast readout speed (>50MHz) is needed, if the pixel size is ~20  m Experience at SLD tells that readout during train could cause beam-induced RF pickup problem At present, no proven technology exists

20. Sub-detector R&D: VTX Our idea: FPCCD By using fine pixel CCDs (FPCCD) with the pixel size of ~5  m and fully depleted epitaxial layer, pixel occupancy can be as low as <1% even if the signal of one bunch train is accumulated and read out between trains R&D status of FPCCD Vertex Detector Simulation study of background rejection using hit cluster shape Study of charge spread and Lorentz angle in fully depleted CCD All dW<10  m

21. Sub-detector R&D: VTX Future plan – R&D needed Design and development of prototype FPCCDs and demonstration of the performance Readout speed ~ 15 MHz Multi port readout Study of wafer thinning and the support structure Development of readout ASIC

22. Sub-detector R&D: TPC Saga, Hiroshima, KEK, Kinki, Kogakuin, Mindanao, TUAT, Tsukuba collaboration (with LCTPC groups) Challenges of ILC TPC High point resolution ( 2m) MWPC readout  MPGD readout Gas choice Large scale (R~2m) structure R&D issues Study of MPGD: GEM and MicroMEGAS Study of chamber gas property: drift velocity, diffusion Positive ion feedback control High density and low material electronics

23. Sub-detector R&D: TPC R&D activity Series of beam tests have been done at KEK PS using small size test chamber with MWPC, GEM, and MicroMEGAS readout The activity is international – with LCTPC groups Collaborators from Canada, France, Germany, Japan, Philippines joined the BT

24. Sub-detector R&D: TPC Data Neumerical Calculation MicroMEGAS Pad : 2.3 mm Diffusion Constnat : 193 Neff = 27.5 f :  function Data: MicroMEGAS B = 1 T Gas: Ar-isobutane (5%) Pad: 2.3 mm Pads Resolution as a function of drift distance Results of the beam tests Resolution is understood in terms of pad pitch, diffusion, pad response function, and the effective number of electrons To improve resolution, smaller pad size or larger charge width (resistive anode) is effective

25. Sub-detector R&D: TPC Resolution with resistive anode 4 GeV/c  + beam  ~ 0°,  ~ 0°  0 = (52±1)  m N eff = 22  0 (stat.)

26. Sub-detector R&D: TPC Future plan of TPC R&D Search for better gas mixture and MPGD configuration to achieve the TPC performance goal Measurement of pad response function and avalanche fluctuation using single electrons for better understanding of spatial resolution Study of positive ion back flow suppression Simulation study of MPGD TPC Performance tests with large prototypes using PCMAG and prototype electronics under international cooperation

27. Sub-detector R&D: CAL Kobe, Niigata, Shinshu, Tsukuba, Mindanao, JINR, Korean universities R&D for scintillator based calorimeter (CAL) Challenges Achieve sufficient granularity with reasonable cost Optimize the configuration to achieve the performance goal Develop best PFA algorithm

28. Sub-detector R&D: CAL Configuration EM CAL: Tungsten- Scintillator strip sandwich Hadron CAL: Lead- Scintillator strip/tile sandwich Wavelength shifting fiber and MPPC readout for both CALs MPPC: Multi Pixel Photon Counter

29. Sub-detector R&D: CAL Photon sensor R&D – MPPC Merit of MPPC Work in Magnetic Field Very compact and can be directly mounted on the fiber High gain (~10 6 ) with a low bias voltage (25~80V) Photon counting capability at room temperature

30. Sub-detector R&D: CAL R&D status and plan MPPC testing in progress MPPC R&D : Larger size (1.5mm) and more pixel (>2000) is necessary ECAL prototype construction in progress and beam tests at DESY in 2006 and at FNAL in 2007(?) are planned Improvement of PFA algorithm is necessary HCAL beam test is indispensable to understand hadronic shower

31. Sub-detector R&D Future prospects Each sub-detector R&D group has future plan (desire) towards LOI Required funding increases significantly in order to make further progress, but the established funding level is extremely low in Japan Therefore, it is hard to present reliable future prospects now Funding level in each region for coming 3-5 years (from “ILC detector R&D status report and urgent requirements for funding”, edited by WWS Detector R&D Panel) (For priority-1 items only)

32. GLD DOD GLD concept study and sub-detector R&D activities are crystallized into “GLD Detector Outline Document” It consists of the following sections; Description of the concept Detector sub-systems Physics performances and a separate document on cost estimate To be finalized by April 15 th DOD is not the goal. It is a starting point for further optimization of GLD detector design.

33. Summary Japanese group is actively involved in GLD detector concept study There are sub-detector R&D activities in Japan for vertex detector, TPC, and calorimeter But future prospects of these activities are not clear due to lack of established funding Activities of GLD detector concept study and sub- detector R&D are crystallized into “GLD Detector Outline Document”, which will be published soon These activities should be continued to make more optimized and realistic detector design, and more precise cost estimation