High-resolution, fast and radiation-hard silicon tracking station

CBM collaboration meeting March 2005

STS working groupSTS working group

Status STS

Conceptual design (CDR) First round of simulations (TSR)

ITS with 3 pixel planes SIT with 4 equidistant planes,

strip technology through out Design iteration (partly in TSR)

Optimize configuration Include HitProducers in

simulation Physics performance studies for

different physics cases Final design (TDP 2006?!)

Senors/FE chip, module, support+cooling, readout

Technological feasibility (R&D) Full performance simulation

To

do

Facts after 2nd round of simulations

Beam pipe of 1 cm Ø

Fluence above 1016

Pixel

Strip

Depends strongly on the physics case.

Alternative configurations for

different observables possible.

Only strip sensors for stations 4 to 7 (SIT) if micro2 strips are used close to the

beam!

First 3 stations (ITS) inside the vacuum! Possibly shielded

against good beam vacuum by a foil.

Is this the last word

Challenging tasks of the tracking station (I)

Micro vertex reconstruction (main task of the ITS) Secondary vertex reconstruction better 50m (z-

coordinate) Extremely high track density

GeV1%09.0

GeV3%8.0

μm10

MeV102

0

0

021

pX

x

pX

xx

X

x

pd

x

Both high resolution Both high resolution andand a respectively a respectively low material budget low material budget are needed.are needed.

D0→K

D0→K-+

Material budget / plane

I. Vassiliev

Challenging tasks of the tracking station (II)

Background rejection in low mass dielectron spectroscopy Reconstruction of "incomplete" tracks Needs probably much more redundancy

ee 0 ee

If these are not reconstructed ..

.. those will form a fake open pair

-electrons are a huge concern

Yield in 1st station: 5/gold ion passing the (1%) target 5000 at frame rates of 10 s and 109 ions/s !?

P. Koczon

Possible configuration (B-TeV inspired)

Outer section of plane 3 outside the vacuum!

Highest granularity not needed there

Allows using thin vacuum window

Detectors can be moved in two halfs.

Remove sensors from beam area during focusing

Only two different module geometries

Optional for MAPS or Hybrids

Generic designs for simulation

Hybrid-like Material budget Resolution

MAPS-like Radiation hardness Read-out speed

MAPS material budget a first assessment by Michael Deveaux

Stacking of sensors due to inactive read-out area

Design VELO (LHCb) inspired

0.29 %

MAPS R&D

Dense program of chip submission in 2005 MIMOSA 9 → factor 2 lower signal than expected MIMOSA 10 → MIMOSTAR1 first prototype for STAR IT MIMOSA 11 → Various sensor geometries for studying

aspects of radiation tolerance MIMOSA 12 → Multiple charge storage on-pixel,

aspects of capacitor performance MIMOSA 13 → Current readout

faster, better noise immunity

Transfer of one test station to Frankfurt Support R&D efforts starting with MIMOSA11 Aspects of cryogenic operation

Assessment for GIGATRACKER

NA48: CERN-SPSC-2004-029 (K+→) Concept (only small area needs to be covered)

High rate: 40 MHz / cm2 100 ps time resolution Fluence 4.5 1014 cm2 (12 Mrad) 0.13 m envisaged

http://na48.web.cern.ch/NA48/NA48-3/groups/gigatracker/

x/X0 < 0.6%

STS working packages

STS

ITS SIT

MAPS Hybrid

Overall configuration

R&D

Module design

R&D

Module design

Sensor design

FEE R&D

Module design

Readout interface

Integration & Infrastructure

Design optimization

Design Optimization

Mainframe

Algorithms Digitizers

Final configuration

Tracking groups

STS group

MAPSHitProducer

(Michael)

Strip HitProducer

(Valeri)

Physics benchmarks:

Open charm

• i.e. 10.000 D0/run

Low-mass dielectrons

• S/B < 1/5

• ?

Towards a Design Proposal

Vertex tracker (ITS) Main tracker (SIT)

MAPS fall back Strip

Design optimization Granularity Resolution Configuration

GSI, IReS GSI, IKF Obninsk

Choice of technology Sensor Readout Module/plane design

IReS MSU/MEPHI

R&D IReS, IKF MSU/MEPHI

Infrastructure/Environment

Management