Aurore Savoy-Navarro LPNHE-Universités de Paris 6&7 SilC Collaboration R&D Advances since St Malo Si-Envelope design Mechanics Electronics Future Prospects

SiLC COLLABORATION Status: International Collaboration started early 2002 [ChicagoWorkshop] Aim: To pursue R&D on Si detectors for tracking at future LC Who: Santa Cruz (Dorfan et al), SLAC (Jaros et al), Colorado, Tokyo, Wayne(Bellwied et al), MIT (Fisher), LPNHE, BNL; Several European & Asian (Japan, Korea and Taiwan) Institutes are also joining Most of these groups have already a large or even sometime proeminent expertise in this R&D domain. Two detectors are considered:  The all-Si-tracker (SD)  The Si-envelope (LD or TESLA) See:

Si-Tracking concepts: All-Si-tracker (SD) Si-envelope

The SiLC Collaboration is pursuing independently of the detector concept, a generic R&D that focuses on:  Various sensor technologies Short µstrips, long µstrips, SDD (contacts with Canberra, Hamamatsu, ST Microelectronics)  R&D on Electronics FEE for each sensor case Digitization, trigger logic, Timing info(SDD) Cabling & packaging Power cycling issues  R&D on Mechanics Transparency, hermeticity, architecture, support modularity, rigidity, deformation studies, cabling, cooling, alignement  Simulation studies Developing the necessary tools: Full simulation (GEANT4-based) Fast simulation, Pattern recognition, Tracking reconstruction algorithm(s) Studies on Physics issues and needs (precision, dE/dX…), Detector performance studies, including comparisons between different detector techniques and concepts. A lot is underway in the Collaboration, with many different tools available (legacy from previous experiments)

WE BENEFIT FROM: WE BENEFIT FROM: the already existing expertise gained by: the already existing expertise gained by: Precursors: Precursors: The LEP Microvertex detectors (6 µstrip sensors/ladder) STAR (SDD µvertex)  ALICE Larger area Si-tracking: CDF at Run II: 3.5 m2 µstrip detectors AMS with about 6 m2 µstrip ladders [up to 15x4.2cm length] ATLAS and CMS very large area Si-trackers [the next generation: ~ 200 m2] Working in collaboration with these experiments. OUR PURPOSE is to start from the present state-of-the-art to push further this R&D for outcomes not only for the LC, but also for:  upgrades of the LHC experiments  developments of trackers for astro particle experiments

!!!!!!!!!!!!!THINNESS!!!!!!!!!!! Long µstrips/ladders Long shaping time FEE Power cycling Passive cooling (ultimate?!) Fine granularity (pitch size) high precision (centroid) Thin detectors (<or = 300µm) ratio width/pitch! Reduced cost Sadrozinsky ‘s law Thin mechanical structure If B-field = 5 T (compact detector), demanding magnet design

R&D ADVANCES since St MALO J.E Augustin,M. Baubillier, M. Berggren, B. Canton, C. Carimalo, C. Chapron, W. DaSilva, D. Imbault, F. Kapusta, H. Lebbolo, F. Rossel, A. Savoy- Navarro, D. Vincent [LPNHE-Paris] 1)Setting up the Lab Test bench: Contacts with AMS and CMS Collaboration and Hamamatsu 2) Pursuing R&D on mechanics:  EUCLID  CATIA (Detailed design)  Progress on the Si-FCH design  Studies of cooling issues: on a mechanical prototype of the drawer with appropriate software packages  First realizations of C-fiber prototypes, to test feasibility of drawers & honeycomb structure

1)TEST BENCH for Si-SENSORS & FEE SCIPP+SLAC: Currently developing the simu of the Si-detector pulse development to begin to understand questions associated with high B-field, diffusion, pulse sharing etc… that will affect the design of the FEE chip. Present scope: to demonstrate low-noise and power switching for the FEE amplifier of a long shaping time readout system. Testing a 2m long ladder made with 10cm long sensors, 250µm pitch (GLAST) LPNHE Paris: Currently installing the test bench: 1st ladder prototype = 5 AMS sensors (4.2 cm long, 56 µm pitch, 200 µm width, bonding allowing to test: 20, 40, 60, 80 cm… long µstrips and various RO pitch sizes) 2nd ladder prototype = 6 CMS-TOB sensors, > or = 9.45 x 6 cm long µstrips (183 µm pitch, 500 µm width)

Objectives: Objectives: 6 ‘’  12 ‘’ wafers 500 µm  300 µm width 183 µm  50 to 100 µm pitch Double-sided (double metalisation) Better yield (> 50%) & cheaper Preliminary FEE studies: Preliminary FEE studies: characterizing output signals on test bench, looking for low noise preamp on the market & developing one.

2) R&D on Mechanics: Basic elements of the detector design Ladder drawer Honeycomb structure

Moving from EUCLID to CATIA The long drawer is made of 5 ladders; each ladder is made of 6 CMS-TOB sensors. The drawer is about 2.5 m long. Ladder: 6 sensors

R&D on Mechanics con’td: Si-FCH DESIGN Modularity: ladders with 4,5or 6 sensors 4 Quadrants 4 XUV made of 6 2-sided sensors: 4 XU & 2 VV XUVVUXXUVVUX

The Si-Envelope, CATIA- CAD design

CATIA design of the outside central part of the Si-Envelope: SET CATIA design of the Si-FCH honeycomb structure

The Si-envelope components in a few numbers: Si-envelope Component Items Total Number Si-FCH (XUV)Nb of layers Nb of ladders, 4 sensors Nb of ladders, 5 sensors Nb of ladders, 6 sensors Nb of RO channels/endcap Power dissipation 4 XU + 2 VV , Watts SETNb of layers Nb of ladders Nb of RO channels Power dissipation 2 1-sided sided ,293, Watts SITNb of layers Nb of ladders Nb of RO channels Power dissipation 2 2-sided = , Watts

R&D on Mechanics cont’d: C-FIBER PROTOTYPES Honeycomb structure: Several French firms contacted  No pb foreseen to realize the proposed honeycomb structure within the required dimensions C-fiber structure for drawers: Mechanical studies, design and fabrication of tools + cast of C-fiber structure drawer section done at LPNHE-PCC 1st prototype drawer structure: 2 mm thick & 20 cm long. Need to go to 1 mm thick & 2.5m long  Doable but easier by cutting structure into 2 pieces.

R&D on Mechanics cont’d: COOLING STUDIES & TESTS on PROTOS Aim: Test if water cooling at end of the 2.5 m long drawer OK vs FEE power dissipation (0.2watt/ladder) Modelling of 2.5 m drawer with C-fiber board, made of 5 parts, each one =60cm ladder. FEE = resistor (0.8 or 1.4 Watt). Higher power dissipation & very localized so much worse than anticipated. Natural air convection: T°C varies at most 8°C

A simple water cooling at the edge of the drawer looks sufficient Measuring temperature decrease in the resistor neighbourhood  rapid decrease Measuring Temperature without natural convection (~80% suppressed), T(cooling water=19degC)  results similar to natural convection, so Grad T<<10 degC

Simulation studies: developing full GEANT4-based simu. The detailed CAD mechanical design = instrumental to define the geometry DB = 1st step Tokyo is developing a full GEANT4 simu for the SD tracker  So full simulation work is really starting now.

All these issues are underway. A lot has been achieved since the first ECFA-DESY Extended Studies Workshop at Cracow in September ‘01  First results on long ladder characterization & FEE developments (next ECFA-DESY Workshop)  R&D on Mechanics aiming on: Detailed CAD Design, CATIA-based of the Si-Envelope. Building realistic prototypes of: a long ladder (Lab), a long drawer(Lab) a piece of honeycomb support structure(Industry)  Cooling tests on realistic mechanical proto & comparison with software computations (ACORD, SAMCEF)  Simulation studies: Main aim = developing a GEANT4-based detailed simulation (including pattern recognition)  Further developments of the SiLC Collaboration