H. Wieman1STAR HFT CD1 Review, BNL, November 2009 STAR HFT PIXEL Detector WBS 1.2 Howard Wieman LBNL

H. Wieman 1STAR HFT CD1 Review, BNL, November 2009

STAR

HFT PIXEL DetectorWBS 1.2

Howard Wieman LBNL


STARTopics - PXL (WBS 1.2)

• PXL design and status• Deliverables• Development and

Construction Plan• Schedule• Risks• Cost• Manpower


STARPixel geometry. These inner two layers provide the projection precision

2.5 cm radius

8 cm radius

Inner layer

Outer layer

End view

One of two half cylinders

20 cm

coverage +-1

total 40 ladders


STARSome pixel features and specifications

Pointing resolution (12 19GeV/pc) m

Layers Layer 1 at 2.5 cm radiusLayer 2 at 8 cm radius

Pixel size 18.4 m X 18.4 m

Hit resolution 8 m rms

Position stability 6 m (20 m envelope)

Radiation thickness per layer

X/X0 = 0.37%

Number of pixels 436 M

Integration time (affects pileup) 0.2 ms

Radiation tolerance 300 kRad- 1011 to 1012 1 MeV n equiv/cm2

Rapid detector replacement

< 8 Hours

criticalanddifficult

more than a factor of 3 better than other vertex detectors (ATLAS, ALICE and PHENIX)


STARPerformance features

• 50 m Silicon detector chips, MAPS– thin– small pixels, high

resolution

• Air cooling • Mechanical stability

Hybrid uncertainty area--------------------------------MAPS uncertainty area

pointing accuracy comparison


STARAlternate Technologies Considered

• Hybrid– X0 large (1.2%)

– Pixel Size large (50 m x 450 m)– Specialized manufacturing - not readily available

• CCDs– Limited radiation tolerance– Slow frame rate, pileup issues– Specialized manufacturing

• DEPFET– Specialized manufacturing– very aggressive unproven technology


STARStability requirement drives design choices

• The detector ladders are thinned silicon, on a flex kapton/aluminum cable

• The large CTE difference between silicon and kapton is a potential source of thermal induced deformation even with modest 10-15 deg C temperature swings

• Two methods of control– ALICE style carbon

composite sector support beam with large moment of inertia

– Soft decoupling adhesive bonding ladder layers


STARHFT PXL status

• Mechanical stability analysis completed (controlled to 20 m)– thermal deformation– gravity induced sag– humidity induced deformation– support vibration

0 100 200 300 400 5001 10

4

1 103

0.01

0.1

1

10

100

1 103

based on red PSD curve fig. 2based on blue PSD curve of fig. 2

RMS vibration displacement relative to support

frequency (Hz)

RM

S (

mic

ron

s)


STARHFT PXL status-thermal analysis and testing

• Silicon power: 100 raised to 170 mW/cm2 (~ power of sunlight)

• 350 W total Si + drivers


STARPXL status - thermal test results

Hot spots for images at location 0-21 cm (3 cm step): 41.2, 42.5, 41.4, 41.6, 41.4, 40.5, 40.1, 38.3 ºC

“sensor” heaters: ~230 W

Pt heaters: ~25 W

Driver heaters: ~40 W

Total: ~295 W

Airflow 16 m/s

max

min

room

∆T above ambient room temperature: 11.5 deg C


STARHFT PXL status – air flow vibration tests

air velocity probetwo positions shown

capacitance vibration probetwo positions shown

carbon fiber sector beam

adjustablewall for airturn around

air in

air out

0 2 4 6 8 10 120

2

4

6

8

10

measured vibration with negative pressure modemeasured vibration with positive pressure mode

Ladder Vibration

air velocity (m/s)vib

ration

RM

S (

mic

rons)

5.77

8.66

8

no reinforcement at the end8 µm

3 µm3 µm

2 µm

11 µm

4 µm

reinforcedend


STARHFT PXL status – fabrication and tooling


STARHFT PXL status – insertion design

insertion mechanism to guide detector around beam pipe and beam pipe support

uses track and carriage with hinge and cam to guide into final docking position


STARHFT PXL status – installation design

• a well controlled method for installation of the pixel detector has been developed with emphasis on ease of operation and avoidance of detector risk

• The PXL assembly will be enclosed in a carrying box that is equipped for transfer of the detector assembly into the PXL support tube

• Once inserted on tracks the detector is guided into position locking kinematic mounts


STARPXL Deliverables

– Pixel Insertion Structure– Pixel Insertion Tool– a total of 10 sectors, with each sector containing:

• one ladder at a radius of 2.5 cm• three ladders at a radius of 8.0 cm

– With each ladder containing:• ten Si detector elements• one readout board

– two DAQ receiver PCs– PC based control and monitoring system– two clam shells, with 5 sectors integrated and aligned on each clam shell– The two clam shells will be installed in Pixel Insertion Tools, ready for insertion

onto the New Cone Structure– One additional complete detector and sufficient sector and populated ladder

components to have the capability to fabricate two more complete detector assemblies

– Provide services including cabling and cooling


STARPXL WBS items (high level)

• 1.2.1 PXL Mechanics– 1.2.1.1 Module Support (Sector)– 1.2.1.2 Detector Support (D-Tube/Kinematic Mount)– 1.2.1.3 Insertion Mechanism and Internal Service Support

• 1.2.2 PXL Electronics– 1.2.2.1 Phase-1 PXL Sensor Chips– 1.2.2.2 Final PXL Sensor Chips– 1.2.2.3 Ladder Cable– 1.2.2.4 PXL Prototype Ladder Assembly– 1.2.2.5 Read-Out Electronics– 1.2.2.6 PXL Sensor Ladder Production

• 1.2.3 Detector Assembly– 1.2.3.1 Prototype Sector Assembly– 1.2.3.2 D-Tube Assembly and Survey Tool (Engineering)– 1.2.3.3 Sector Mount and Survey (Engineering)– 1.2.3.4 Final Assembly (Engineering)– 1.2.3.5 Production Sector Assembly– 1.2.3.6 D-Tube Assembly– 1.2.3.7 Sector Mount and Survey– 1.2.3.8 Final Assembly (Production)– 1.2.3.9 System Test (Production)

• 1.2.4 Infrastructure– 1.2.4.1 Cables– 1.2.4.2 Cooling Services– 1.2.4.3 Rack Equipment

• 1.2.5 Installation– 1.2.5.1 Pixel Installation in-situ


STARElectronics Development Plan

• Develop sensor chips, 3 generation program (WBS 1.2.2.2)• Develop readout electronics (WBS 1.2.2.5)

– STAR compatible readout system - limited channel count– Upgrade to full detector capability

• Develop flex PC readout cable (WBS 1.2.2.3)– copper version– aluminum version

• Develop chip testing and characterization system (WBS 1.2.2.5, 1.2.2.6)– chip level– probe test level

• Production testing of ladders (WBS 1.2.2.6)


STARMechanical Development plan

• Design detector structures (WBS 1.2.1.1, 1.2.1.2, 1.2.3) • Design fabrication tooling (WBS 1.2.1.1, 1.2.3)• Design installation (WBS 1.2.1.3, 1.2.5)• Analyze structure stability and cooling (WBS 1.2.1.3)• Prototype structures using developed tooling (WBS 1.2.1.1,1.2.1.2, 1.2.1.3)• Test structure stability and cooling (WBS 1.2.1.1,1.2.1.2, 1.2.1.3)• Prototype installation and insertion (WBS 1.2.1.2, 1.2.1.3)• Prototype sectors with prototype sensors (WBS 1.2.1.1, 1.2.1.2)• Design and build cooling plant (WBS 1.2.4.2)• Test engineering prototype • Install and operate engineering prototype (WBS 1.2.5)• Produce final detector sectors (WBS 1.2.3.8)• Test final detector system (WBS 1.2.3.9)• Install and operate final detector system (WBS 1.2.5)


STARmilestones


STARPXL Risk Assessment, selected high risk examples

WBS # Description of Risk Mitigation1.2.1.1 Air cooling, new technology, high technical risk Early in the program carry out detailed cooling

analysis, computational fluid dynamics (CFD), followed with tests using a full scale realistic prototype mock-up.

1.2.1.1 Air cooling, source of vibration, high technical risk

Early in the program carry out vibration and deformation measurements of the sector structure in the appropriate air flow stream

1.2.1.1 New sector/ladder support technology, high technical risk

Perform early FEA analysis of the structures and measure prototype structures as soon as possible to determine if the proposed design meets the requirements

1.2.2.1 Risk that aluminum cable fabrication leads to technical and schedule problems. (high risk)

schedule float, visit vendor and work collaboratively and test production capabilities early

1.2.2.1 Risk of radiation damage to inner silicon layer. The expected dose for maximum Au+ Au luminosity is 1011 to 1012 1 MeV n equiv/cm2 per season. This is comparable to tolerance levels of our detectors

Improve measurements of rad hardness and STAR radiation levels. Design for rapid replacement capability.


STAR


STARElectronic Manpower (5 yr period)

name title inst. function FTE PXL

Leo Greiner Sr. Sci. Eng

LBNL Lead detector electronics 5

Michal Szelezniak Post doc LBNL MAPS and readout expert, software, firmware

2

Xiangming Sun Post doc LBNL Readout expert, software, firmware 2

TBD Post doc software, firmware 2

Chin Vu Electronic Eng

LBNL Readout, testing, firmware .5

Thorsten Stezelberger

Electronic Eng

LBNL Readout, firmware .5

Jo Schambach Physicist TBD Readout, firmware, testing 3

Rhonda Witharm E Tech LBNL wire bonding, fabrication 1.5

Jacque Bell E Tech LBNL fabrication 1.5

John Wolf E Tech LBNL fabrication 1.5


STARMechanics Manpower (5 yr period)

name title inst. function FTE PXL

Eric Anderssen

Mechanical Eng

LBNL Lead Eng. .2

Howard Wieman

Physicist LBNL mechanical design, analysis, testing

4

TBD Mechanical Eng

mechanical design, production supervision

1.2

Tom Johnston

M Tech LBNL composite fabrication, assembly

2.4

Mario Cepeda

M Tech LBNL fabrication, assembly 2.4

additional M Techs LBNL fabrication, assembly 2.4

Michal Szelezniak

Post doc LBNL mechanical testing .2


STARSummary

• MAPS technology development going well• Readout electronics well advanced and tested• Very low mass detector support designs have passed

multiple analysis tests and prototype tests addressing cooling and position stability.

• Tooling is in place and tested for sector/ladder production

• Concept designs for installation and insertion are well advanced

• Risks have been identified and are being addressed at an early stage

• Design and testing have matured sufficiently to make accurate cost estimates


STARbackup


STARSensor and Readout Development Plan

Mimostar–2 30 µm pixel, 128 x 128 array1.7 ms integration time1 analog outputMimostar–330 µm pixel, 320 x 640 array2.0 ms integration time2 analog outputsPhase–130 µm pixel, 640 x 640 array640 µs integration time, CDS4 binary digital outputsFinal (Ultimate)18.4 µm pixel, 1024 x 1088 array≤ 200 µs integration time, CDS,zero suppression2 digital outputs (addresses)

Sensor Sensor RDO

50 MHz readout clockJTAG interface, control

infrastructureADCs, FPGA CDS & cluster

findingzero suppression ≤ 4 sensor simultaneous

readout


infrastructurezero suppression120 sensor simultaneous

readout


infrastructure400 sensor simultaneous

readout(full system)

DO

NE

PR

OT

OT

YP

ED

Gen

1

1

2

3


STAR

Documents

H. Wieman1STAR HFT CD1 Review, BNL, November 2009 STAR HFT PIXEL Detector WBS 1.2 Howard Wieman LBNL