Vertex Detector. ECFA/DESY Workshop Amsterdam, April 2003 Chris Damerell. Conceptual design requirements (update) Detector technology options

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1 Vertex Detector ECFA/DESY Workshop Amsterdam, April 2003 Chris Damerell Conceptual design requirements (update) Detector technology options Route to convergence Construction, commissioning, operation and physics Synergy with other science The purpose of this detector is flavour ID (charm as well as b tagging), plus higher goals such as enabling ID of decay electrons, and measuring vertex charge and charge dipole, as pioneered in SLD, for distinguishing b from b jets, and c from c jets CJSD/ECFA/DESY-Amsterdam/pg1

2 Conceptual design requirements Cos θ = 0.96 Ladders Gasket seal Barrel 1 L = 100mm Barrel 2-5 L = 250mm Beam-Pipe Foam Cryostat and Faraday Cage Stripline Similar layout considered in Asia, North America and Europe CJSD/ECFA/DESY-Amsterdam/pg2

3 Features common to all technologies: Pixel-based, around 1 Gpixel total (microstrips faded out in 1993, in view of SLD performance, and estimated backgrounds) Inner layer as close as possible to IP, subject to background constraints (12-15 mm radius) Concentric long barrels, 3-hits to cos θ = 096. (endcap trkg useful, but not for flavour ID) 5 layers for robust standalone tracking [outer tracking system less of a tracker, more of a momenter ] Measure space points with precision < 5 µm in each layer Layer thickness reduced from 0.4% (SLD) to 0.1% X 0 (subject to stability requirements) Excellent suppression/recognition of gamma conversions ID of decay electrons Layer 1 readout time < 50 µ s required for TESLA (to on-detector storage of sparse data) 5 ms OK for NLC/JLC or CLIC Excellent noise/pickup suppression essential, to avoid overwhelming any DAQ system Modest radiation hardness will be sufficient While the goals are clear, the means to get there are not. Numerous options, but all require extensive R&D, and have potential showstoppers CJSD/ECFA/DESY-Amsterdam/pg3

4 Detector Technology Options Everyone agrees on silicon pixels, but which architecture? Imagine more than one technology meets the performance goals. How to choose? Layer thickness within tracking volume Secondary criterion: layer thickness beyond tracking volume [forward tracking cares about this!] Potential wells Generic Pixel detector CCD + CMOS readout MAPS (1) MAPS (2) DEPFET HAPS In both cases, the material budget could be driven by the power dissipation (if liquid cooling were required). So, try to keep to watts or tens of watts at most. [SLD had 15 W for 307 Mpixels] CJSD/ECFA/DESY-Amsterdam/pg4

5 n layer Depletion edge ~20µm active p(epi) p/p + (edge) x x x x x x p + (bulk) Particle trajectory CJSD/ECFA/DESY-Amsterdam/pg5

6 Route to convergence Preferred technology(ies) to be selected on basis of full-size, fully operational prototype ladders (around 2010?) Choice probably time dependent: what can be ready for startup could well be superseded later [eg at SLC: silicon microstrips were replaced by CCDs in 1990] Convenient access to IR is an essential requirement (for the entire inner detector system) R&D groups should resist pressure from funding agencies to pick the winner. Premature technology choice would degrade the physics potential Who remembers what was the favoured SLC vertex detector technology in 1982? CJSD/ECFA/DESY-Amsterdam/pg6

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8 Linear Collider Vertex Detector Workshop January 8, 2003 University of Texas, Arlington Location: Science Hall Room 200 The meeting has been re-scheduled under the meeting ID To join by phone: Call in the US Press 1 to attend a meeting Enter the meeting ID: 7913, followed by # Press 1 again to confirm correct meeting ID Speak your name into the phone, then press # Press 1 again to join the conference; your name will be announced. Time: 15:00-19:00, US Central Time 21:00-01:00, UK 22:00-02:00, Europe 06:00-10:00 January 9, Japan & Korea Session Organizers: Chris Damerell, Akiya Miyamota, Natalie Roe, Kang Joo Sang All talks are 15 minutes + 5 minutes for discussion CJSD/ECFA/DESY-Amsterdam/pg8

9 TIME (US Central) TITLE OF TALK SPEAKER 15:00 Monolithic Active Pixel option ps pdf Marc Winter, CERN 15:20 Monolithic Active Pixel option pdf Renato Turchetto, Rutherford 15:40 CCD option pdf Konstantin Stefanov, Rutherford 16:00 DEPFET option pdf Marcel Trimpl, Bonn 16:20 SOI pixel option pdf Halina Niemiec, Krakow 16:40 Physics Simulations pdf Nicolo de Groot, Bristol 17:00 Break 17:20 Oregon/Yale CCD R&D and Radiation Damage Studies pdf ps ppt Nikolai Sinev, U. of Oregon 17:40 GEANT4 simulation of vertex detector beam background pdf Tsukasa Aso, Toyama Nat'l College 18:00 CCD radiation damage test with 150 MeV electrons pdf Yasuhiro Sugimoto, KEK 18:20 Silicon Fab and Beam Test Result pdf Hwanbae Park, Kyungpook Nat'l Univ. 18:40 H -> c cbar pdf GeumBong Yu, Korea Univ. Last modified: Monday, January 6, 2003 Send Comments to naroe@lbl.gov CJSD/ECFA/DESY-Amsterdam/pg9

10 Construction, Commissioning, Operation & Physics When choice is made, some groups (technically oriented) will prefer to develop their technology for other applications or possible upgrades Others (particle physics oriented) will wish to contribute to the construction of the first detector(s) The detector construction should be encouraged as a world-wide endeavour, in spirit of GDN SLD ladders (via UPS) SanJose SLAC e2v Brunel SLAC Yale MIT SLAC Make mbds Test mbds Fit CCDs Mech QC Functional test Fit blocks Opt survey Intstall Physics: Those who constructed and understand the detector will be major players (as in SLD) For the present, the key questions are what detector quality is needed for physics: Charm tag Vertex charge Charge dipole Gamma conversion (e.g. for clean electron as well as muon ID, permitting correction for missing neutrinos in B and D decay) Exploration of this new continent is at an early stage: don t jump to premature conclusions CJSD/ECFA/DESY-Amsterdam/pg10

11 purity efficiency CJSD/ECFA/DESY-Amsterdam/pg11 purity efficiency

12 Synergy with other science Pixel detectors are uniquely inter-disciplinary Example from the fall of the wall in structural biology (J Hajdu, TESLA Colloquium) 120 Hz frame-rate needed at LCLS (with 14 bit dynamic range) SNAP (600 Mpixels), XEUS, Fast Gigapixel-scale imaging systems are widely needed, and the LC vertex detector community is making a strong contribution to their development CJSD/ECFA/DESY-Amsterdam/pg12