HEP GROUPMEETING18.12.07

work on theATLAS UPGRADE

T.J.Fraser

ATLAS Inner Detector Upgrade summary: Replace the existing TRT, existing SCT Barrel and end caps and pixel

detector with possibly 5 barrels SCT and discs at ends, and new pixeldetector inside SCT barrels. For the SCT this will mean lots more modules.Modules are at a conceptual stage maybe with hybrid with 40 ASICs connecting to a power bus on the edge. These would operate at high speed using 160MHz clock with serial readout of ABCN but there are various options………eg parallel option clocked at slower 40 MHz.SERIAL POWERING is favoured as in theory it would save a lot of materialbut this will need serious risk mitigation strategies to protect against failureseg OPEN in serial chain – loss of whole stave!, NOISE, SHORTS etc somust be able to isolate a module. One stave will have 10 modules minimum.Irradiation testing of Readout materials have started, more studies in 2008.Module sensors: silicon strip detector specification made, irradiation started,testing from March 2008. Date for Final Design Review beginning of 2010for Barrel followed by Production Readiness Review. Finish production forBarrel modules April 2012.LHC SHUTDOWN scheduled for 2015 – 2016 with SLHC running fromspring/summer 2016. Plan to add early separation dipoles maybe INdetectors at around 6m from IP. Maybe add CRAB CAVITIES at small angle.

ATLAS Inner Detector Upgrade summary: To reach 10 , increase beam current or change bunch cross section and

crossing angle. RF cavities located around the IP or in 2 locations of the LHC.25ns spacing versus 50 ns spacing being debated.Radiation: NEUTRON MODERATOR for INNER TRACKER likely – willimpact on space envelope inside cryostat. The baseline is 5cm lining thecalorimeters. 5cm is a LOT of space but this seems to be the optimum toreduce fluences – but can’t be hermetic – places where services go throughprevent this.IP magnets and the ID reach radiation damage limit at 700fb-1 whichcould be at around 2014 so can’t delay!Various dates on the schedule (rough estimates) are:General TDR (Technical Design Review) 2010 – CONCEPTS FIXEDASSEMBLE PARTS 2011 – 2013ASSEMBLE STRUCTURES on surface 2012 – 2014INSTALL IN PIT 2015STARTUP 2016

SERVICES REVIEW not before March 2008 – lots of work – what services can be reused – reliability – available space. We are setting up a workingfile for services materials which contains info mass/space occupation etc.

35

ATLAS UPGRADEID BARREL END REGION

TJFraser WP7 meeting 08.10.07

Looking at impact of services routing off the barrel end-with current proposed layout of ID…..

Looking at Thermal barrier feedthroughs as part ofsupermodule assemblies

Constraints on services – Hot vs Cold gap options

LS LAYERS 1 and 2R 950, R750, L 3800

SS LAYERS 1, 2 and 3

R 600, R 490, R 380, L 2000

services from inner barrelsmust route 900mm to outer barrel end

services will line end of short barrels and inner surface of outer layers

services from inner barrel must share spacewith wheel sections inside outer barrel

Feedthroughs (as part of supermodule assembly, one persupermodule) fit into gaps in the thermal barrier.Layout of gaps would depend on the siting ofand shape of the thermal barrier.Shape of feedthroughs would depend on type ofservices – if LMT type then a rotational aspectcould be included. Multi-service feedthroughs like thiscould only be used if sited close to detector end.

Thermal barrier sandwich

Feedthrough – could bedesigned to come apart orhave holes largeenough forconnectors,with separateseals

services from barrel

insulatedmulti-feedthroughsone per supermodule

‘wheels’

in ‘warm’ gapseparate thermal barrier

outer barrel

inner barrel

thermalbarrier

services separated into groups for channeling

WARM

insulated ‘single-service’ feedthroughs

‘wheels’

in ‘cold’ gap.No feedthroughs here but would need patch panelsfor readout/TTC PCBssomewhere in cold gap.

thermal barrier

outer barrel

inner barrel

thermalbarrier

COLD

services from barrel

CO

NC

LUS

ION

S:

GENERAL LAYOUT:Services from barrel on current strawman layout follow atortuous route – presents mass where not wanted and difficulties of access during and after installation.5 barrels all the same length would present fewer problemsfor services and less mass as services gap would be shorter.

WARM vs COLD GAP:Warm gap: more space needed for thermal barriers, activecooling pipe insulation and feedthroughs – also means more material where not wanted.Cold gap: services and thermal barriers take up less spaceand therefore less mass but would still need space forpatch panels for some services inside due to limits onlengths and transitions. No insulation needed on cooling (?)Size of single entity – installation difficult if not split up.

NUMEROUS POSSIBILITIES (or should this be impossibilities?) for barrel end layouts until basic decisionsare made about layout and thermal management.

Barrel services minimum space allocation in Z ‘Strawman’ layout and Spider… layout

WARM and COLD GAP versions

Services envelope in Z: In order to reserve space allocation - need to useplaces in the layout where the maximum accumulation of services in Zoccur – cannot use an average as it will not be possible to squashservices into gaps to equalise the occupation.Need to know which existing services are to be kept and if the existingchannels/ducts have to be re-used - before making useful layout in R/PHIfor barrel ends.

example: x-section in Z for services accumulation, barrels 1, 2 and 3:

29mm 10 24 21

thermalbarrier &feedthroughs

uninsulatedcooling pipes& manifolds

cooling connectorsbus tapes/cableswith ‘twist’ factor

84mm TJF

84mm in Z

>150mm in R (insufficient clearance)

>160mm in Z

Barrel services minimum space allocation in Z (‘Strawman’ layout)

Z=00

B1

B2

B3

B4

B5

How will services from Bs 1,2 and 3 be supported on the inside of B4? Will need separate support cylinderor rings for this, adding to spaceoccupancy and material.Services at barrel ENDS also needsupports for connectors/strain relief.

COLD GAP version

services in Z: bus tapes, connectors, cooling pipes, connectors and manifolds TJF

96mm in Z

>162mm in R (insufficient clearance)

>172mm in Z

Barrel services minimum space allocation in Z (‘Strawman’ layout)

Z=00

B1

B2

B3

B4

B5

Thermal barrier will need to serve asservices support as well – if not, thenadd this to thickness. Coolingexhaust pipes will need insulation –6mm thick ie 12mm added here.

WARM GAP version

services in Z: bus tapes, connectors, insulated cooling pipes, connectors and manifolds

TJF

84mm in Z

Barrel services minimum space allocation in Z (‘Spider…’ layout)

Z=00

B1

B2

B3

B4

B5

COLD GAP version

130mm in ZAdvantages of simplified barrel layout:

avoids two 90 bends in services routejust one large services ‘spider’ so canorganise services into channelsonly one type of support needed forconnectors/strain relief at barrel ends

0

services in Z: bus tapes, connectors, cooling pipes, connectors and manifoldsTJF

96mm in Z

Barrel services minimum space allocation in Z (‘Spider…’ layout)

Z=00

B1

B2

B3

B4

B5

Thermal barrier will need to serve asservices support as well – if not, thenadd this to thickness. Coolingexhaust pipes will need insulation –6mm thick ie 12mm added here.Not as good as the Cold gap versionbut better than both Strawman layouts

WARM GAP version

142mm in Z

services in Z: bus tapes, connectors, insulated cooling pipes, connectors and manifolds

TJF

ATLAS Tracker Upgrade - Services at Barrel Ends:Scenario where services are routed through existing services channels on cryostat shown on the next 3 slides ie:Old TRT channels used for fibres, power and sensor cables and input cooling pipesOld SCT cooling exhaust channels used for samepurpose in the Upgrade

Could possibly work for 108 supermodules (with lots of manifolding for cooling pipes)Wouldn’t work if outer barrels were included – these would need to use existing power cable channels but there would beno space in the existing cooling exhaust channels, so newchannels eg one per quadrant would have to be created inorder to keep each set together for maximum cooling efficiency. Design of layout on the cryostat is crucial to thedesign of the layout on the barrel ends!

Evap.cooling routing offbarrel end.

inputexhaustexhaustmanifold

3

11.2522.5

45.0

rows perQuadrant:

11

9

7

45

3

4

5

6

6

7

6 exhaustpipes to‘old’ coolingchannel incryostat

7 7

input pipesin ‘TRT’channels(need manifolds)

exhaustmanifold

TJF 28/06/07half length cooling loops

11.2522.5

45.0

rows perQuadrant:

11

9

7

TJF 28/06/07

exhaustcoolingonly

power andsensor cablesgo in old TRTchannels

power andsensorcables in 4dedicatedchannels perquadrantshown as one‘bunch’ persupermodule

11.2522.5

45.0

rows perQuadrant:

11

9

7

TJF 18/07/07

exhaustcoolingonly

power, sensor cables,fibres and input pipesgo in old TRT channels

optofibrerouting:one fibre fromeach PCB joinsone 12 wayribbon:9 ribbons perquadrant

single fibresribbon

four PCBs per supermodule

CURRENT ATLAS SCT BARREL – view of end barrel services for the 4 barrels –these form a dense ‘thicket’ on the barrel ends and beyond. The upgrade will try toavoid this and minimise mass and complexity….however this won’t be easy!

CURRENT SCTBARREL –installation of onebarrel inside theothers.

Silicon moduleson cylindricalsupport cylindermade of carbonfibre.

Large servicessupport structurenecessary to storelong lengths ofservices and connectors withinthe profile of thebarrel.

The servicesradiating from thebarrel on the radialsupport have to befolded into thisstructure forintegration withthe TRT -Transition RadiationTracker

CURRENT SCTBARREL andTRT being installedin the cryostat inthe ATLAS pit. Itslides in on siderails.

This is the SCTservices supportstructure. TheSCT barrel ishidden inside theTRT barrel

The orange painted cradleis removedonce the SCTis installed.

Conclusion:

It has taken over 10 years to arrive at the stagewhere the Inner Detector is ready to run in the

present form with TRT and SCT barrel andend caps all worked on in parallel by different

Groups - but there will only be 6 years to producethe Upgrade version, so radical departuresin philosophy and design are unlikely to bechosen unless they present a simplification

of the current design!