Summary STS working group

Design optimizationSTS (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

Algorithms Digitizers

Final configuration

Tracking groups

STS group

MAPS:Michaels talk

Strip:Tatianas talk

Valery

Si strip STS_4 Layout Si strip STS_4 Layout

Basic Elements: Inner : 6x2 cm Middle : 6x4 cmOuter : 6X12 cm

-20 cm

+20 cm

Read out

Valery Savielev,Obninsk State Univ.

Si strip STS_6 Layout Si strip STS_6 Layout

Basic Elements: Inner : 6x4 cm Middle : 6x12 cmOuter : 6X20 cm

+40 cm

-40 cm

Read out

+4cm

- 4cm

Valery Savielev,Obninsk State Univ.

Digitization result

number of zone

num

ber

of h

its

3-d STS 4-th STS 5-th STS

6-th STS 7-th STS

T.Galatyuk October 6-8 2004 CBM collaboration meeting 9

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

100 200 300 400

1000

2000

3000

4000

5000

6000

100 200 300 400

500

1000

1500

2000

2500

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@ires.in2p3.fr)

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 (B2/B1) must be as small as possible

Matrix of Pixel

Control ELN

Sparcification

Memori-sation

Smart Detector Reticle

Band Height of non-sensitive part B2

Sensitive part

Control and processing partADC

Band Height of sensitive part

B1

Hayet Kebbati,GSI/IReS

Towards a Design Proposal

Vertex tracker Main tracker

MAPS fall back Strip

Design optimization Granularity Resolution Configuration

GSI Obninsk

Choice of technology Sensor Readout

IReS MSU/MEPHI

R&D IReS MSU/MEPHI

Infrastructure/Environment

Management

The end ...

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 ~ 16-21 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 80-90 % 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