ATLAS Pixel Detector

Service Quarter Panel UpdateAnd

PP1 Work

July 4, 2006Pixel Integration Meeting

M Cepeda, S Dardin, K Kennedy, R Post, M Pereira, J Wyckoff, M Gilchriese, J Alonso, LBNL Berkeley, CA

D Laporte, LPNHE Paris

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorProduction Status and Dry Fits of SQP

• Final Integration of SQP delayed• SQP composed of 2 OSP and 2 ISP panels which are

~80% of the work– these are produced in an independent operation, and this portion

of production is progressing mostly without interruption, though some accumulated delays

• Primarily, this delays first article delivery, but does not telegraph directly to final article delivery– Causes problems on the CERN side of production thru delayed

start– Potentially puts SQP integration on project critical path

• Integration delayed due to increased demand for trial fit of finished production SQP into Dummy PST on Real BPSS.– Proposed option to fix Type 0 barrel cables caused concerns for

interference— solution exceeded design envelope– Have never fit the PP1 end with all cables thru PST

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorClearance Issues

• Clearance between Pixel Package and PST is 3mm– SQP with Cables have an envelope of R225mm

• Uncertainty in model v.s. as-built at the 1mm level– To validate clearance to the 1mm level, real parts must be tried.– Increased scope to include full trial fit of First-Article on BPSS into

Prototype PST shell

• Confidence high enough now after the first results of trials fits to begin preparation on SQP-A34 for delivery as First Article– First (now formerly-first) article, SQP-A12 being used for Trial fits—

will summarize activity in further slides– Will keep A12 at LBNL for further exercise in trial fit

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorTrial Fit Overview

• A1-2 inners have been mounted on backbone• An A1-2 outer has been mounted on the backbone with

A1-2 inner• A1-2 inners on backbone have been mounted on BPSS• In general, the fit to nominal dimensions is excellent

and there are only two significant modifications that are required– Open up the slots in the fiber guides on the bottom of the OSP and

the top of the ISP to increase clearance for tubes. Might be OK without this but safer to open up

– Tabs on CF bottom piece on ISP nearest IP have 2mm clearance holes but the tapped holes in the mating SLA parts glued to the BPSS are 3mm. Holes have to be opened or slotted from the low Z end.

• There are a few spots in which there is an interference of bolt heads(socket heads) requiring either cutting down the heads, changing to flat heads or some local countersinking.

• In principle this means that most structures are fitting together as planned—Cables at PP0 and PP1 are the issue

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorType 0 cable potential interference at PP0

• Envelope is R225: PP1 Quarter plate outer radius (yellow)

• Potential mod to T0 connector exceeded envelope by 1mm

• Added tie-downs to connector plate also included ‘Envelope Checking Features’

• Actual trial fit results follow

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorCable Clearance(1)

• Two rows of barrel cables placed on PP0 edge.• Envelopes checked relative to SLA Strain Relief

Structure• SLA Part later used to verify SQP to PST Clearance

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorCable Clearance(2)

• Pile up at first connector can be made near same as at tab• 0.75 mm shim fits comfortably under SLA tab.

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorCable Clearance(3)

0.75 mm shim fits under tab at edgeLots of clearance nearer centerSpent 1 min arranging cables, coulddo better with some work, but not much

Tab thickness is 0.75mm here

Conclusion: have 1.5mm clearance to envelopeIF CABLES ARE THE SAME AS THESE OR SMALLER

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorPP0 in PST Setup

Shim backbone to bring clearance between outside of longeron on backbone to shell of about 15.5mm

These spacers are 14mm highDouble stick tape underneathRealize not in correct z positionBut easier to reach and measureOn other end

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorResults

4.3mm

4.2mm

4.2mm3.9mm

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorGaining Clearance at PP0

• Before Trial fit, investigated several modification options to increase PP0 clearance if needed

• Intended to determine how much needed from trial fit• The overview of these mods are the following

– The ISP is moved radially inward, tilted in the PP0 region– The tubes are moved radially inward, tilted in the PP0 region– The OSP can then be moved radially inward, tilted in the PP0 region

• The maximum additional clearance that can be obtained in this way doing all, is estimated to be 1.5 to 2mm

• Currently, only plan subset of these modifications (ISP mods)• Preliminary trial fit showed good accordance with CAD Model,

but still need to finish with both ISP and OSP on backbone

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorISP Modifications (required)

Reduce thickness of these tabs by 1.5mm. Chamfer edges

Cut slot for 3mm clearance

Mill tab and CF back from edge by about 1.25 mm to clear SLA

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorISP Modifications(required)

Put 1mm shim here between SLA and CF panel

Cut 3/16” slots here and bring height of web to 5.75mm. All locations

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorISP Modifications (required)

Coral shim represent opto heat spreader.Add additional 1.25mm shim between heatspreader and PP0(preferred) or remake heat spreaders

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorOSP Modification more Painful

Increase opening in SLA parts glued to longeron by machining existing parts or remaking(preferred) by 1mm in all tube locations

Glue on 1/32” aluminum splints here to improve strength along entire length

Remake or cut down cap pieces by 1mm Cut 3/16” slots here and bring height of web to 5.75mm. All locations

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorBackbone Modification (very painful)

Face down aluminum surface by 1.5-2mm

Face down tabs by 1.5-2mm

Cut down ground tree piece by 1.5-2mm

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorPP1 Clearance

• Wires outside of PP1 that go to LEMO connector, must be arranged to allow insertion

• Clearance for ISP wires between OSP boards and HX Tubes was insufficient—had to re-configure PP1 Quarterplates and Cruciform.

• Trial Fit with old quarterplates to verify nominal clearances and build tolerances complete (results follow)

• Trial fit with mock up of new quarter plate geometry in work

• New Quarter plate and Cruciform in production—available this week(?)

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel Detector¼ Panel Clearance-Orientation

¼ plates inside tube

Extension rails can affect centering accuracy—adjusted them to help centering.

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel Detector¼ Panels Clearance - Measurements

Point 1

Point 4

Point 8

Point 12

Point 16Point Inches mm

1 0.133 3.37822 0.115 2.9213 0.108 2.74324 0.094 2.38765 0.092 2.33686 0.084 2.13367 0.076 1.93048 0.089 2.26069 0.098 2.4892

10 0.116 2.946411 0.142 3.606812 0.142 3.606813 0.15 3.8114 0.154 3.911615 0.144 3.657616 0.132 3.3528

Average 0.116813 2.967038Max 0.154 3.9116Min 0.076 1.9304

Gap between ¼ plates and inside of shell averages to 3mmCentering of rails in Prototype Shell off by ~0.5mm (?)

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorPP1 Layout Changes

• HX Locations maintained—Only ISP and OSP Penetrations moved• OSP got as close as possible to HX Tubes, ISP moved out as far as

possible while still maintaining adequate Cruciform width

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorPP1 Insertion Configuration

PP1 insertion can and Rail rider shown above

Wires wrapped around can with new PP1 Quarterplate geometry

End-view of Can showing envelope for external wires

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorWork on PP1b region at Paris (LPNHE)

• Engineer, Didier Laporte, from Paris, working on producing both CAD Model and Physical Mockup

• Physical Mockup to be ‘Simplified’ with interference envelopes, but of sufficient detail to test Cable and Tube connections.

• Will use it to exercise connecting PP1 in pit• Pictures of Model follow

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel Detector

Pixel octant 8

Pixel octant 7Pixel octant 6

Pixel octant 5

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorOctant 8

• Map of Cables in tray to LEMO PP1b connector drives cable routing

• Cables connected in layers

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel DetectorConflicts Between Cable Boots

• Radial increase of PP1b required to remove interference between Boots of T2 cables on different Panels

• Have Request in with ID to investigate this, have tentative OK to continue in this direction

• Need to finalize formal request for this increase—preferably by next TMB

July 2006ID Week

Tech Staff LBNL

ATLAS Pixel Detector

Flat cablesBeam pipes

front plate

Flange

End plate

Wall

Simplification for Mockup