entwicklung des silizium-spurdetektorsystems f ür das cbm -experiment bei fair

Entwicklung des Silizium-Spurdetektorsystems für das CBM-Experiment bei FAIR

Outline

Detector simulations

Radiation environment

Prototyping of components

Radoslaw Karabowicz,Johann M. Heuser

CBM CollaborationGSI, Darmstadt

DPG Frühjahrstagung, Darmstadt, 11.3.2008

GSI as of 2008

Facility for

Antiproton and

Ion

ResearchSIS 100/300

DPG Conference, Mar 11th 2008 Radoslaw Karabowicz 2

CBM @ FAIR

the

Compressed

Baryonic

MatterExperiment

CBM Experimental Setup


RingImaging

CHerenkov

MUonCHamber

Micro-Vertex

Detector+

SiliconTrackingSystem

DipoleMagnet

TransitionRadiationDetector

TimeOf

Flight

ElectroCALorimeter

Silicon Tracking

System:-8 double-sided micro-strip silicon stations

-length of 100cm

-with thickness of 300m

-and acceptance of about 2.5 to 25 degrees

-1.3 million channels

-readout electronics, support structures, cables implemented

Tracking challengeTracking challengeAu+Au central collision at 25 AGeV (UrQMD): → ~1000 charged particles→ ~700 in the STS detector acceptance

Goal is to track particles:

-quickly

-efficiently

-effectively

107 minimum bias collisions per second have to by analyzed online

Hit densities in central part exceed 10/cm2/central event

To perform physics analysis high tracking efficiency with good momentum and position resolution is crucial


High granularity detector

station 1 ( at 30 cm)

station 8 (at 100cm)

Sensors’ occupancy in one Au+Au central 25 AGeV collision

Double-sided micro-strip sensor

vertical front side strips

15º rotated back side strips

60 m

horizontal size 6cm

vert

ical

siz

e fr

om 2

to

6cm



Low mass detector

x[cm]

y[c

m]

- silicon detector thickness:

currently 0.3% x0 (300m)

- station with cables and support

structure: up to 1% x0

-total vertex/tracking system: < 15% x0

x/x0

x/x0

Radiation length thicknessstation 5 (z = 60cm)

STS detector

6 million 10 GeV/c pions in Geant


Tracking results

Track finding and fitting takes 78ms on Pentium4 processor

- 1000 central Au+Au collisions simulated in UrQMD, - transported in the STS geometry by GEANT,- track finding: Cellular Automaton,- track fitting: Kalman Filter.

Ionizing dose

Ansatz:CBM Lifetime: 3x1014 minimum bias collisions

Maximum dose at a level of around 20 Mrads


Radiation environment

station 5 (z = 60cm)

station 8 (z = 100cm)station 1 (z = 30cm) Mrad Mrad

Mrad

STS 5 STS 6

STS 8

neutron fluence1 MeV n equivalence

-minimum bias Au+Au collision at 25 AGeV (UrQMD)

-transported in FLUKA

CBM lifetime:~3 x 1014 interactions


STS 1

Radiation environment cont’d

STS 7

1015

1014

1013

1012

1011

1015

1014

1013

1012

1011

1015

1014

1013

1012

1011

1015

1014

1013

1012

1011

More than 3 x 1014 neutron equivalents per square centimeter

!! LHC radiation regime !!

Long, stiff, low material support structures ALICE design

Hardware development


Station 1

sensors

readout

cables

support

Modular structure

Expertise in Russia

more on Friday, 15.00, R. Lalik

Readout and cables

1024 strips50 µm pitch2 cm long

55 cm long, 1024 lines, 100 µm pitch55 cm long, 1024 lines, 100 µm pitch

14 µm Al on 10 µm Kapton14 µm Al on 10 µm Kapton

Proto

types p

roduced

Kharkiv, U

krain

e

Fast, self-triggering, precise, radiation tolerant readout chip

n-XYTER

CBM-XYTER

Expertise

Krakow, P

oland

GSI, Germ

any

Long (up to 50cm) but ultra thin (~50m) cables with a small pitch(~100m)


DETNI design

ALICE design

New "Technology wafer": Focus on radiation hardness.

Silicon sensorsDetector prototyping:

Micro-strip detector prototype CBM01,GSI-CIS, Erfurt.

Detector test board

Produced A

ug 2007

CIS E

rfurt,

Germ

any

Produced F

eb 2008

GSI - beam test with 3.5 GeV protons in September 2008


Realistic detector response

Sector view:Front strips in blueBack strips in greenMC points in circlesReconstructed hits: stars

Size of plot [cm]Position in STS:XYZ

Front strips’ ADC distributionBack strips’ ADC distribution

Simple Event Display


Backup solution:Single sided micro-strip detectors.

Already done:Geometry composed of 16 stations, grouped in pairs, where first station has vertical, and the second rotated strips and they are separated by 0.5cm.


Single sided detectors 1

Digitizer firing one strip in the middle of the point.

Ideal hit finder combining strips belonging to one track.


Single sided detectors 2

realistic description of the STS geometry

efficient and quick tracking

double-sided micro-strip silicon sensors, readout chips (n-XYTER), test boards already in hand and ready to use

work on realistic detector response undergoing

backup solution: single-sided micro-strip silicon detectors

PREPARING SEPTEMBER TEST BEAM IN GSI


Summary

Back-up slides

DPG Conference, Mar 11th 2008 Radoslaw Karabowicz

Characterization of CBM01 at CISCharacterization of CBM01 at CIS

IV and CV characterization of CBM01B1, CBM01B2, CBM02

reported at CBM Meeting September 2007

U [V]

I [µ

A]

U[V]

I [µ

A]

U [V]

1/C

2 [p

F-

2]


DDetector module etector module pre-pre-prototypeprototypes, KINR Kiev s, KINR Kiev

CBM01-B1 detector:

p-side on test board

CBM01 detector, chip cable on carbon fibre support


Mapping of inter-strip charge charing with laser positioning system

CBM01-B1226 Ra from p-side, p-strips 5@6

CBM01 – first measurements at KINR CBM01 – first measurements at KINR

ES

trip

E Strip+1

0 10 20 30 40 50 60 700

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Voltage, V

Cu

rren

t,

A

VA - characteristic

Vitya (16.02.08 am)Sasha (21.02.08)V.O. (16.02.08 pm)

U [V]

I [µ

A]

Current-Voltage behaviour

Charge collection near surface

µm

ES

trip


entwicklung des silizium-spurdetektorsystems f ür das cbm -experiment bei fair

Documents

geantdpg conference

mmdpg conference

cmdpg conference

mradsdpg conference

interactionsdpg conference

au au central

central au au collisions

radiation environment