PHENIX Silicon Vertex Tracker

PHENIX Silicon Vertex Tracker

Mechanical Requirements

Stability requirement, short and long 25 µm

Low radiation length <0.5%

Low CTE

High stiffness-to-weight ratio

Room temperature operation -- desirable

Cooling – H2O desirable

Kinematically mounted off Central Magnet

PHENIX Silicon Vertex Tracker

Mechanical SpecificationsCentral Barrel

layer radius 2.5,6,8,10 cm

layer length 30 cm

pixel size 50 μm x 425 μm

strips 80 μm x 3cm

pixels( 1st layer) ~1.9M

strips(2,3,4 layer) ~165k

azimuthal coverage 320 deg

End caps(each)

inner radius 2.5 cm

outer radius 18cm

disk z position(at z= 2.5cm) 20,26,32,38 cm

pixel size 50 μm x 4 mm

total pixels ~2.0M

azimuthal coverage 360 deg

PHENIX Silicon Vertex TrackerSimulated Performance

Barrel

occupancy

1st layer 1%

2nd layer 11.5%

3rd layer 7.2%

4th layer 4.8%

resolution

DCA <100 µm

Endcaps

occupancy

all disks <3%

resolution <100 µm

PHENIX Silicon Vertex Tracker

Integration

Designed to coexist with TPC < 20 cm radius.Clam shell design to fit around beam pipe.Radiation length ~ 1% per layer goalBarrel and end cap sections are separate units ( i.e. ATLAS type)

Staging Option 1

Phase One --year 1Design for barrel with strips first – no pixels or end caps

Phase Two - after year 1Second design for complete barrel and end caps

Option 2Design for barrel with option to add pixels, add end caps later

N-type single-sided strip sensor developed by BNL (Z. Li)• Thickness : 400um (0.43 % X0), 250um (0.26% X0) for mass prod.

• Size : 3cm*6cm, Pitch : 80um, 2-dim readout : x- and u-direction

• #ch per sensor : 384 ch/dir * 4 dir =1536 ch

Drawn by Yuji Goto

Silicon Strip Sensor

x

u

x

u

Prototype Sensor ModulePrototype module development is on going.• Performance of the sensor will be tested w/ cosmic ray and beam at KEK.

• Readout chip : VA2 (Viking 128 ch CMOS, analog multiplexer, 1us peaking time)

DraftOnly this

Toward Ladder Structurein Vertex Tracker

• Barrel layer length: ~30cm

• #chip : 12 readout chip/sensor

• #sensor : 4 or 5 sensor/ladder

• Cooling : dependent on readout chip

Ex. SVX3D : 3.5mW/ch * 128ch/chip * 60sensor/ladder = 27 W/ladder

Liquid cooling will be required.

• Cabling : Cu(Al) / Polyimide hybrid for low material budget

• Ladder material : ex. CFRP (Carbon Reinforced Polymer)

• Total material budget goal : 1% X0 per layer

Mock-up of Barrel Support StructureMaterial : CFRP (Carbon-Fiber Reinforced Polymer)

Pictures and drawings : http://rarfaxp.riken.go.jp/~tojo/20020729/mockup20020729.htm

Precision, strength, deformation and material budget will be measured.

ATLAS Vertex Detector• Support and cooling structures for ATLAS vertex detectors• Thermo-mechanical design

- dimensional stability, low Z, high stiffness, heat removal capacity

B-layer services

end section (2)

center frame sectiondisks (10)

internal end-cone (2)

interior barrel layers

0 50cm

ATLAS: Support Frame

• Support Frame End Section– All GFRP Construction

• XN80/CE Facings• XN50/CE Honeycomb

– High dimensional accuracy (<.001”)

Finished Prototype

Load Test (Prism)

Prototype Frame During Fabrication

ATLAS: Silicon Detector Backplanes• Pixel detector support & cooling

– Extreme stability ( < 10 µm @ -15ºC)– High heat flux (10,000 W/m2), active cooling circuit– Low mass ( < 2 kg/m2)

– High stiffness ( > 100 Hz)

all carbon-carbon tube~3.2 mm ID

0.25 mm wall thickness

facing overhang

tube extensions

mountingpoints

0

10

cm

PHENIX Silicon Vertex Tracker

PHENIX Silicon Vertex Tracker