Summary STS working group Design optimization STS (Strip) layout R&D (MAPS) Working packages

Manpower !STS activities momentarily not backed by EU funding FP6 I3 (SOSDET) R&D on monolithic (MAPS, amorphous Si) and ultra-thin hybrid (Giga-tracker) sensors. not funded in favor of diamond → standard technologically!! FP6 Design close call STS foreseen for second round (i.e. 2005) now cancelled in favor of proposals from first round  Total manpower in STS project of O(1 FTE)

Generic simulation Design as of now: 7 stations at 5,10,20,40,60,80,100 cm from target 100 mm (1,2) and 200 mm (3-7) thick 10, 20  m resolution in both coordinates Needed for proposal Simulation including pad, strip structure Optimized configuration

Design optimization Design Optimization Mainframe AlgorithmsDigitizers Final configuration Tracking groups STS group MAPS: Michaels talk Strip: Tatianas talk Valery

Si strip STS_4 Layout Basic Elements: Inner : 6x2 cm Middle : 6x4 cm Outer :6X12 cm -20 cm +20 cm Read out Valery Savielev, Obninsk State Univ.

Si strip STS_6 Layout Basic Elements: Inner : 6x4 cm Middle : 6x12 cm Outer :6X20 cm +40 cm -40 cm Read out +4cm - 4cm Valery Savielev, Obninsk State Univ.

Digitization result number of zone number of hits 3-d STS 4-th STS 5-th STS 6-th STS 7-th STS T.GalatyukOctober CBM collaboration meeting9 MC hits (points) reconstructed hits Tatiana Galatyuk, GSI/Kiev

R&D MAPS; IReS, LEPSI, (GSI) radiation tolerance readout speed Driven by common interest between NLC and CBM community Strip detectors; MEPHI, MSU Thin double-sided sensors Read-out (FEE) chip no activity yet due to missing funding

Successor1 before and after 1MRad X-Rays Observations (Priliminary): No significant influence on gain Charge collected in 1 pixel [ADC] Charge collected in 9 pixels [ADC] T = -15°C t = ~ 200µs No significant charge loss CBM collaboration meeting, GSI Darmstadt, 6-8 Oct 2004, Michael Deveaux Michael Deveaux, GSI/IReS

Control and address Electronics Fast signal processing and data sparsification  Signal digitalisation Storage threshold values needed during data sparsification Surface ratio (B 2 /B 1 ) must be as small as possible Matrix of Pixel Control ELN Sparcifi cation Memori- sation Smart Detector Reticle Band Height of non- sensitive part B2B2 Sensitive part Control and processing part ADC Band Height of sensitive part B1B1 Hayet Kebbati, GSI/IReS

Towards a Design Proposal Vertex trackerMain tracker MAPSfall backStrip Design optimization Granularity Resolution Configuration GSIObninsk Choice of technology Sensor Readout IReSMSU/MEPHI R&DIReSMSU/MEPHI Infrastructure/ Environment Management

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Choice of technology Availability Minimize own development effort (manpower) LHC silicon trackers needed 800 man years R&D Conservative fall-back solutions for future technology options

Problems / Open questions Material budget increase to balance position resolution! identification of conversion electrons Efficiency? Realistic simulation for track fragment reconstruction Efficiency Fake rate Magnetic field Close pair recognition in the inner tracking section Efficiency?  -electrons Vertex reconstruction fast station needed in vacuum?

Oleg Rogachevski, conformal mapping 5,10,20,40,60,80,100 cm, 3 first stations in vacuum, 100 mm (1-2) and 200 mm (3-7) thickness. no delta electrons Hit multiplicity for secondaries peaks at 1-2 hits, 40 % of the hits in the first two stations have no other hits and cannot be reconstructed Efficiency drops from 0.95 to 0.7 below 10 GeV, efficiency > 95 % if 7 hits are observed. Matching with inner track segments, which are incomplete, problematic!!!

Sascha Ierusalimov, STS track fitting Generic simulation Uniform field used 100  m thickness throughout, 20  m resolution best resolution between 1 and 10 GeV ~ 0.7 – 1 % if all hits are present. Vertex reconstruction small systematic shifts < 1  m  ~  m Results from realistic simulation (GEANT-3) Problems broken tracks 2-hit tracks? close tracks?

G. Osakov, track reconstruction a la LIT Old geometry used on average 1.62 ghost tracks efficiency around % only

Pavel Akishin, Polynominal approximation Best resolution reached in this approach. 0.4 %

Pavel Zrelov, Kalman filtering 2-dimensional projection Very precise starting points needed 20  m resolution assumed Parabola used as track model between the detector stations 5-7

Joachim Gläß, Fast tracking Fast Hough transform used Efficiency only above 1 GeV (cut)  amounts to ~0.95 Large ghost rate Needed clock cycle 150 MHz Total number of processing units 200