Pixel UpgradeStatus & Plans

CMS Engineering &

Integration Meeting

CERN, 2. March 2011

R. Horisberger, PSI

Present Pixel Detector with 3 hit coverage works very well !

• 3 barrel layers & 2 F/B disks • easy & quick removal / installation in shut down• designed for luminosity < 1x1034 cm-2 sec-1

• design fluence < 0.6x1015n/cm2 (tolerate more)

Measured resolutionr = 13mz = 25m

Pixel Thresholdsmean = 2450 e

1

• BPIX 3 Layer 4 Layers • FPIX 2x2 Disk 3x2 Disk

Proposed Pixel Upgrade

• CO2 cooling based Ultra Light Mechanics

• Shift material budget out of tracking –region

Increase number pixel tracking points 3 4

Significant X/X0 reduction

pixel tracking & vertexing significant improved and robustified

• ROC modifications for operation up to L ~ 2x1034

• Use same cabling DC/DC converters for power 320MHz digital readout on fibres

• Minimize 1 Layer radius reduced impact xy & z error

2

Shift material budget out of tracking region

Current BPIX Services Upgraded BPIX Services

<2.2 : weight = 16.9 Kg (3 layer) <2.2 : weight = 6.5 Kg (4 layer)

shift out

~1.5 : -conversion for H from 22% to 11% for new 4 Layer Pixel System

Current 3 layerUpgraded 4 layer

Current 2 diskUpgraded 3 layer

Ra

dia

tio

n l

en

gth

Ra

dia

tio

n l

en

gth

3

BPIX / FPIX Envelope Definition & Insertion into CMS

CO2 cooling loopsstainless steel pipeswall thickness = 100diameter =1.8mm

Barrel Supply Tube

Insertion of new system verified

CF hinge

4

BPIX Upgrade Mechanics 1216 modules 81M pixel (1.6 x present BPIX)

If beam pipe r < 22.5 mm 1st Layer: 12 faces <R>=29.5mm 5

(present)

bas

elin

e• Full module type only

Layer 1: R 39mm; 16 faces

Layer 2: R 68mm; 28 faces

Layer 3: R 109mm; 44 faces

Layer 4: R 160mm; 64 faces

Clearance to beam pipe 4mm

current

upgrade

22.5

mm

24.7mm < 29.5mm >

Ultra Light Mechanics BPIX Prototype

100 bar pressure testedTubes, 50 wall thickness

Weight Layer1 42g + 7g CO2 30% of old first layer X/X0

Layer 1

Low mass CO2 cooling pipes

less multiple scattering in impact parameter resolution

Present Pixel Barrel

z-im

pac

t p

aram

. r

es.

[m

]

azimutal angle 6

FPIX Mechanics & Prototype

• inner & outer ring for easier replacement

• 6 disk of 112 sensors each 672 modules

• one module size with 2x8 ROC / module

10’752 ROC’s ~ 44M pixel (2.5 x old FPIX)

CO2 coolingloops

7

Impact Parameter of old / new Pixel System

Beam pipe r<23mm : 16 faces to 12 faces reduce MS term by ~0.75 total 0.75x0.6 = 0.45 !

0<<1.0

0<<1.0

tran

sver

se IP

lon

git

ud

inal

IP

tran

sver

se IP

lon

git

ud

inal

IP

Barrel Region

Barrel Region

Forward Region

Forward Region

0.6

current

upgraded

upgraded

current

8

~0.75

IP estimate for 12 face 1st Layer

Upgrade of Pixel Readout Chain

Data losses removed by ROC

changes:

1) increase depth of Status

- data buffer 32 80 done

- timestamps 12 24 done

2) add readout buffer done

3) 160Mbit/sec serial binary data out now

4) deal with PKAM events DAQ

resync

control interface block CIB

8005 um (52 pixel)

9935

um

80 p

ixel

DC

OL

1

DC

OL

2

DC

OL

3

DC

OL

26

12

tim

e

sta

mp

s3

2 d

ata

bu

ffe

rs

11

76m

300m

PSI46 ROCPresent ROC for 1st Layer:

Luminosity bx-spacing Data Loss

1x1034cm-2s-1 25nsec 4%50nsec 16%

2x1034cm-2s-1 25nsec 15%50nsec ~50%

50nsec operation of LHC was not planned in original ROC architecture in 1998.

125 µm

20 µm

Al core + Cu

Self Bonding EnamelPolyamide

IsolationPolyesterimide

CuAl core

3.125 ns

40m

V

-twisted CCA pair (Copper-Cladded Aluminum)

• 1m long low mass link at 320MHz , chips done !

9

Current / Upgraded Pixel Track Seeding at 2x1034cm-2s-1

upgraded

current

current

upgraded

current

upgraded

Red

uced

data lo

ss and

qu

adru

plet seed

ing

im

pro

ves efficiency an

d red

uces fake rate !

10

b-tagging of Current / Upgraded Pixel System

Current detector

Upgraded detector

~5x fake ratereduction

+25% efficiency gain

Lumiosity =

Efficient b-jet tagging crucial to many physics analysis

e.g. 4-b-jet channel fake rate reduction by factor ~600 or ~2.4 x signal gain

ttbar 80<pt<120 GeV Combined Seondary Vertex Tagger

11

Pixel Upgrade Schedule

13

2011 2012 2013 2014 2015 2016 2017 2018

7 TeV shut down LS1 14 TeV LS2LHC machine

present beampipe

new beampipe (45mm)

CMS open

Pixel (rep/ mod/ test/ inst)

new pixel instal. test

PP1 preparation

CO2 plant (pre) install.

CO2 – pixel load tests

Pixel (instal./comm./oper)

14 TeVTSTS 7 TeV 14 TeVTS TS 14 TeV

( ) ( ) ( )

Pixel tests @ PixTIF

( )

New LHC Schedule drives Pixel Schedule

The new LHC schedule after Chamonix 2011 constraints our possible time planning

New beam pipe for pixel upgrade

CMS Technical Coordination requested in Nov 2010 a CAD design study for a beam pipe diameter that still would be compatible in installation and required clearances with 12 face innermost barrel layer.

BPIX design study finished in Jan. 2011

Considered:

• cabling clearances• inner shield imperfections• beam displacements < 2 mm• minimal overlaps of sensor areas

Conclusion:

• mean 1st layer Si- radius = 29.8 mm• need 2 mm clearance to beam pipe• need adjustable closing mechanism• Beam pipe diameter (outer) = 45 mm !

Installation: Adjust & Close Tests in LS1

Current BPIX design has 7.5mm tolerance from inner shield to beam pipe. Observe ~3.2mm beam pipe displacement to nominal CMS tracker ! (z-dependent)

New upgrade pixel assumes courageous 2 mm tolerance gap to new beam pipe !

Only possible by adjustable BPIX pixel rail feet ! ( how about FPIX? )

Insertion past beam pipe support ring may require closing mechanism in final z-position !

Propose installation tests with duplicate of new upgrade pixel mechanics.

1) test tolerances2) test adjustment to beam pipe displacement3) test closing mechanism in situ

worm gear

BPIX & FPIX should both do these tests !

to be done ~ Mai 2014

CO2-Cooling / Power Pixel Load Tests

BPIX / FPIX service tubes with ohmic power loads and CO2- cooling loops

Ohmic power loads with CO2-cooling.

Propose to build dummy supply tubes with ohmic power loads and CO2 cooling loops with identical power cabling and final cooling loop connections as real detector for PP0.

PP0

Pixel power / cooling load cylinders are used to verify and commission CO2 cooling plant at the PixTIF and the cooling plant in CMS prior to the installation of the new pixel in CMS.

can be shortened

300 m

1176

m

32 d

ata

buff

ers

576

m

12 ti

me

stam

p bu

ffer

s25

2 m

control interface block CIB

8005 um (52 pixel)

9935

um

80 p

ixel

DC

OL

1

DC

OL

2

DC

OL

3

DC

OL

26

Development of digital PSI46 ROC

Reduce data losses by:

1) increase depth of- data buffer 32 80 - timestamps 12 24

2) add readout buffer3) 160Mbit/sec serial binary data out4) deal with PKAM events

Tests with LHC rate beams- rare errors with data- SEU errors

Next data losses term after 1) & 2) is dc-reset loss, removal possible by use of an extra marker bit (*)

modify data buffer logic !

Submission planned Sept. 2011

Submission possible in 2012 !

(*) based on an idea by H-C. Kaestli (2010)

Submission of digital PSI46 ROC

Submission of new digital PSI46dig (September 2011)

Submission with 4 chips / recticle

Qty Name Properties

1 PSI46 present analog readout ROC, as used now in FPIX / BPIX1 PSI46xdb analog readout ROC but with extended deeper data buffers1 PSI46dig digital ROC, extended data buffers & ROC readout buffers1 TBM etc TBM & faster ALT & various test chips

Submission of dc-reset loss corrected PSI46dig (possible 2012)

Submission with 4 chips / recticle

Qty Name Properties

3 PSI46dig digital ROC, extended data buffers & ROC readout buffers1 PSI46digx PSI46dig with dc-reset losses removed

Possible Recticle for September 2011 Submission

21200

HDI-driver chip

LCDS-driver chip

ALT chip

( Kapton cable drivers)

( Faster Analog Level Translator (ALT) chip for read out Opto Hybrid)

TBM chips

Old PSI46 ROC PSI46xdb- analog readout- extended db & ts buffers

PSI46dig- digital readout- extended db & ts buffers- readout buffers- pulse height ADC

mor

e te

st c

hips

redesigned

old TBM

old & PKAM clipping

digital TBM & PKAM clipping

FPIX Pilot Blades with PSI46dig ROC

FPIX mechanics, cooling & cabling was originally designed for 3 disks each side.

Present installed FPIX system has only 2 disks equipped.

All cables, fibres and cooling pipes for 3rd disk exist !

Proposal:

After repair of present FPIX during LS1 insert the 3rd disk mechanic and mount a few pilot blades of old design with new digital ROC (PSI46dig) and provide for these blades a few (already existing) readout fibres with old AOH, but new (faster) ALT chip.

Can operate and commission new digital ROC under realistic conditions (use CMS tracking as beam telescope) and write all the necessary software changes in DAQ, DB and DQM for a smooth and swift transition for the new upgraded pixel system in 2016/17

Available time slot for construction Jan. 2012-Feb. 2013 13 month !

1176

m

32 D

B57

6 m

12 T

S25

2 m

1532

m80

DB

896

m24

TS

288

m35

6 m

present ROC increased buffer sizecompact layout (done)

control interface block CIB

8005 um (52 pixel)

9935

um

80 p

ixel

DC

OL

1

DC

OL

2

DC

OL

3

DC

OL

26

PSI46xdb : analog ROC with extended data buffers

Present ROC with analog coded readout can be significantly improved for beyond LHC luminosity performance at very low radius layer by extended data & time stamp buffers

• PSI46xdb included in combined recticle in planned September 2011 submission.

• ROC becomes 356um larger may use in fresh BPIX 1st layer replacement in LS1 !

Replacement of 1st Layer of BPIX in SL1 ?

Replacement of 1st layer of BPIX with fresh silicon sensors and improved ROC chip with deeper data buffers could allow an efficient 1st BPIX layer operation for LHC running beyond standart luminosities.

Summer 2007, mounted modules of 1st pixel layer

This would cure the dominant dead time producing mechanism (data buffer overflow) and improve the 1st layer data loss (~5%) until installation of the new upgraded 4 layer pixel system with digital readout. For readout and software nothing changes.However, it will distract us from our main mission of a new 4 layer digital pixel system !

Use of PSI46xdb ROC that is logic design step along the path to produce PSI46dig.

Available production time slot Jan. 2012 – Feb. 2013 13 month

MU

X

core

ROC

ROC

ROC

ROC

ROC

ROC

160 MHz bus channel A

160 MHz bus channel B

320 MHz uplinkcoreToken A

Token B

TBM

Data digital pixel module / balanced coding

320 Mbit/s up link

Channel A (8 ROCs)160 Mbit/s Bus

LCDSRECV

160 MHz

320 MHz

LCDSDRV

Channel B (8 ROCs)160 Mbit/s Bus

160 MHz

320 MHz40 MHzPLL

1m micro twisted pair cable

Token A

Token B

A B! A B!

MUX

4

TBM A

4

TBM B

LCDSRECV

SER

SER

core

core

320 MHz read out signal is pseudo balanced by multiplexing by A with !B

good enough for ZARLINK ?

need encoding in TBM ? which? 4b/5b or 8b/10b

2011 2012 2013 2014 2015 2016 2017 2018

7 TeV shut down LS1 14 TeV LS2LHC machine

present beampipe

new beampipe (45mm)

CMS open

Pixel (rep/ mod/ test/ inst)

new pixel instal. test

PP1 preparation

CO2 plant (pre) install.

CO2 – pixel load tests

Pixel (instal./comm./oper)

New FPIX Pilot System for 2013

FPIX Pilot

constructon

14 TeVTSTS 7 TeV 14 TeVTS TS 14 TeV

( ) ( ) ( )

Pixel tests @ PixTIF

Pilot blades with PSI46dig for 3rd FPIX Disk: Jan 2012 – Feb. 2013 13 months ! !

( )

• Chamonix 2011 schedule for LHC has clear constraints for next years to come and the work that needs to be done in LS1.

• Schedule for LS2 not reliable known. Installation in extended TS (2016/17) conceivable.

• Should advance as many pixel installation jobs as possible to LS1. reduce personal irrad. dose; more time to react for problems; reduce task pile-up

• Beam pipe (outer) diameter of 45mm would allow 1st pixel layer radius <r>= 29.8mm

• Requires adjustabel feet to deal with clearance tolerances and disalignment of CMS

• ROC submission planned in Sept. 2011 with PSI46, PSI46xdb, PSI46dig & TBM’s plus extra chips like faster ALT, Gatekeeper etc.

• Propose to install in LS1 the FPIX system with partial equipped 3rd disks using a few pilot blades with the new digital ROC and digital readout chain. Allows concurrent running and commissioning of old & new system. Time slot for construction is very short. (~1 year)

• Common System & Integration (CSI) coordination is a very big task and linked to TC!

Summary & Conclusions

Spare Slides

CSI: Common Systems & Integration (1)

Pixel CSI Coordinator will have to organize and do many things:

• Beam-pipe planning, installation and taking care of all interface issues with the pixel detector (old & new) during Long Shutdown LS1 ~ 2013/14)

• Test installation during LS1 of pixel upgrade mechanics (adjustment & closing) with new beam pipe. Installation platforms, adjustment tools, inspection tools, clearance sensing & control to beam pipe in conjunction with the FPIX & BPIX groups

• Organization & Operations of Pixel Repair Lab at Point5 (dual use old / new pixel)

• Conceive, prepare, organize and get done with all required changes to services in PP1 / PP0 during LS1 that can be  advanced from period in 2016/17. Stay operational with old system till installation of the upgrade pixel detector.

• CO2 Cooling plant: - basic conception, plant design & construction, - piping & sensors for open loop sensing or feed back

- control software and interlocks

• Pixel test facility at TIF (PixTIF): Conception, build up and operation of pixel test facility with correct length piping and CO2 cooling plant test pixel system

• Establishing & Coordination of DAQ / Power & Slow Control for complete system tests at PixTIF

• Shielding & radiation dose management of working people during LS1 & Installation feed back to project planning (dose spreading limits, show stopper ?)

• In situ power load & CO2 cooling tests with ohmic loads on installed service tube dummies and final PP0 LV-cabling & CO2-piping. Design & fabrication of dummy service tubes with ohmic loads for FPIX & BPIX.

• Take care and organize pixel common items:

- CAEN power supplies: firmware changes (2015), planning new units for 2018) - environmental control (humidity control during installation, etc. etc. ) - Optical link components, qualification & production of POH - Pixel FED: adaptation to serial protocol, board-production, etc.

• Installation of new upgrade pixel system in 2016 / 2017

• Prepare Software adaptation for switch over: old pixel new pixel in 2017

CSI: Common Systems & Integration (2)