ECFA-DESY Extended Studies NIKHEF, Amsterdam 1st to 4th April, 2003 Tracking session 31st March 2003 SilC: an International R&D Collaboration to develop Si-tracking technologies for the LC Aurore Savoy-Navarro, LPNHE-Universités de Paris 6&7/IN2P3-CNRS-France

The SiLC Collaboration: Institutions List (still preliminary) Brookhaven National Lab., USA Department of Physics, Michigan U., USA LPNHE-Paris, France University of Peruggia/INFN, Italy, Department of Physics, Tokyo U., Japan SCIPP and UCSC at Santa Cruz, USA University of Torino/INFN, Italy Wayne University, USA [University of Geneva, Switzerland University of Helsinki, Finland University of Pisa/INFN, Italy University of Roma 1/INFN, Italy University of Valencia/CSIC, Spain CNM-Barcelona/CSIC, Spain Charles University in Prague, Czech Rep. Korea, Taiwan]

The SiLC R&D Collaboration is driven by the Physics motivations to build the outmost performing tracking system for the experiment at the future Linear Collider

Two detectors concepts The SD detector (all Si detector) The Si-Envelope: Si-trackers surrounding the TPC Si-FCH SET SIT + FTD

Independent of the detector concepts: Period from 2003 till end 2006 will be dedicated to collaborative worldwide effort on: GENERIC R&D

Starting from the present state-of-the-art The LEP/SLC legacy: First MarkII –SLAC LEP II µvertex  first long ladders & VA FEelectronics The currently running experiments: AMS, CDF II & STAR AMS: 1st very long ladders (up to 15 sensors), fabrication CDF II & AMS : 1st ‘’large area Si-trackers’’, 5 to 6 m2 sophisticated RT Si-data processing (SVT) STAR: 1st ‘’large Si-drift tracker’’, 0.7 m2, Si-drift FE electronics & readout The LHC detectors in construction: ATLAS, CMS & ALICE CMS & ATLAS: Very large area Si-tracking systems (200 m2) ALICE = further improvements wrt STAR Impressive progresses in Si-tracking technology this past decade !!

The R&D Program and Main objectives: from mid 2003 to end 2006 R&D on Si- Sensor technologies R&D on Electronics R&D on Mechanics Simulation Studies and developments Test set-ups Calibration, Monitoring and Slow Control Issues

1.- R&D on Si-sensor technologies Three main streams:  The long µstrips: Main appealing features: drastic diminution of FE channels thus less material and power dissipatio (transparency) high position reso., simplified mechanical design Presently starting from AMS & GLAST exp. (LPNHE, Santa Cruz ) See R.Bellwied’s & B. // ses presentations 1st prototyped long ladder (see ASN talk in tracking session) R&D on wafers: 6’’->12’’, thinner, smaller pitch, D.S. & yield>50%

 The Si-drift sensors: Appealing features: Equivalent to solid state TPC, thus 3-D tracker, with timing measurement (nanosecond), Position reso = 10 to 15 µm New developments are underway starting from STAR present expertise (see R. Bellwied’s talk): thinning of the sensors and improved timing and position resolutions with new sensors  New solide state sensor technologies: SiLC will be investigating all possible new SS-technologies of interest for our applicationS, in collaboration with high tech firms and Solid State Research Labs. Depending the locations and/or functions various Si-sensor technos will have to be considered.

2.- R&D on electronics  Development of the VFE electronics for each Si-sensor optimization of S/N and power dissipation => power cycling ?  Digital architecture: on-detector electronics Sparsification, pedestal substraction on-detector electronics Charge = pulseheight measurement clusterization for point resolution (preprocessing data at earliest possible stage) Timing for noise rejection (& Z measurement ??) « Triggering » or realtime data processing using capabilities of Standalone Si-tracking system Data transmission from detector to outside world Going to submicroelectronics ( <0.25 µm) Packaging and Cabling (TAB etc…) Integration in the overall readout & DAQ system

VFE electronics: main present electronics issue 1.- VFE for long µstrips: => Santa Cruz: simulation studies and design of a dedicated preamplifier-long shaper with power- cycling circuit, 0.25 µm techno (see Bruce’s talk) => LPNHE-Paris: Detailed studies on the test bench of VA-based F.E. electronics (VA-64-hdr and VA-1) from LEP & AMS and other available FE’s. Forthcoming design of a VFE following similar lines to SCIPP project (collab) 2.- VFE Si-drift Following the lines of STAR + ALICE improvements (cf Rene)

Si-readout schema: very preliminary The first stage in the readout chain is the digization; Some preliminary thoughts on how to implement on-detector this function, and related issues. But still many questions in ??? In the case of Si-drift: {PASA + SCA + ADC} into a single chip as for ALICE is considered also for the LC

3.-R&D on Mechanics Mechanics are a major issue to build the appropriate Si-trackers for the future LC detector. Main challenges = need for:  An ‘’extreme’’ transparency or as less material as (im)possible  Very high precision in position, mechanical stability  large surface detector  cheap and easy to build devices THIS IMPLIES a real and multi-facets R&D on mechanics to achieve a step forward in mechanics as compared to presently running or under construction Si-trackers.

Main R&D Mechanics topics:  Detailed CAD design of a Si-tracking system  Transparency related issues studies  Cooling studies: test on mechanical prototypes and CAD computations  Tests and studies on materials and approaches (mechanical structures, cooling etc…)  Mechanical precision issues  Alignement  Mechanical constraints and stabiltiy  Technique to build a large number of basic mechanical elements: study of technology transfer to Industry  Studies on mechanical prototypes (feasibility of mechanical design components, Industry transfers etc…)

3.1- Detailed CAD design of the Si-envelope and outcomes Allows to address all the possible Si-tracking cases: SET=large area Si-tracker Si-FCH = forward Si-tracker (ASN’s talk at tracking // session) SIT intermediate Si-tracker =>CAD detailed design reveals pbs =>Gives inputs for geometry DB in GEANT4 based simus

3.2- Cooling studies On prototypes and comparing with CAD dedicated software computations parallel session)

4.-Test set-ups Most of the Institutions are well equipped in various Lab test benches in clean rooms. A few of them are getting equipped. To be developed: the appropriate test bench for various mechanical prototypes test issues Foreseen: Beam test by fall 2006 with a full prototype possibly preceeded by intermediate test beam studies ( under discussion)

5.- Calibration, Monitoring and Slow control issues Three main issues will be addressed:  The handling of distorsions in the tracking system  The alignement issues  The very high precision in position required Expertise developed for the LHC on these issues will be very fruitful, as for instance: Interferometer system for ATLAS by the Michigan group

6.- Simulations and developments studies SiLC is benefitting from both FAST MC’s expertise (SGV, LCTRK..) and GEANT4-based starting expertise Work to be done or underway:  Detailed pattern reconstruction, including forward direction  GEANT-4 detailed simu developt.  Various detector set-ups & technos comparisons including TPC  Background studies[ including GEANT simulation of beam line & related detector issues (ex: forward..)]  Calorimeter-assisted tracking (for SD)  Physics studies to establish performan ce requirements

Schedule & Milestones for the Si-SENSOR R&D Proto Beam Test New sensor technos Si-Drift techno R&D Long Si µstrips R&D Milestones

Schedule/milestones for electronics R&D R&D on Long Si-µstrip F.E. R&D on Si- Drift F.E. R&D readout R&D RT data proc.

Schedule/milestones for mechanics R&D

CONCLUDING REMARKS Proposal will be submitted in about one week from now, Presentation at the next PRC opened session, May 7th and 8th, 2003