1. Engineering Division 1 Mechanical and Integration HFT CD0 25-February 2008, BNL Eric Anderssen, LBNL

2. Engineering Division Pixel Mechanics Recent Effort Contracted ARES Incorporated for analysis on cooling, precision mount design and refinement of ladder stability. –Phone meetings weekly First results – –May need Sub-Ambient Cooling to meet goals set at time of contract—understanding benefit of cold operation not yet understood –Simplified Precision Mount –Sector Stability seems adequate –Moisture adsorption needs further work First stage report due by March –Results of Hygro-Thermo-Structural Stability (and vibration) –Kinematic mount design and load transfer Move toward construction of prototypes to be verified against models Some details from ARES analyses presented in Back-up Following are some pictures of current design 2

3. Engineering Division HFT Pixel Structure Installed (Concept) 3 ‘D-Tubes’ covered by Pixel Services Articulation Pantograph Beam Pipe Supports Articulation Guides Support Rails and Table Also supports External Service ‘Card Cages’ ‘ISC’

4. Engineering Division Components Developed with Ares 4 Kinematic MountsInlet Duct ‘Strong Back’ with Cam-Follower (part of articulation hinge) ‘D’ Tube Load Transfer Mechanisms

5. Engineering Division Follower guided insertion operation Open Closed 5 Clears Beam Pipe over Large Diameter Clearance for Beam Pipe Supports and Kinematic Mounts Final Motion engages Kinematic Mounts Articulation Region

6. Engineering Division Pixel placement concept Detector assembly slides in on rails—this is a change from previous 3- Bladed Iris design Parallelogram hinges support the two detector halves while sliding Cam and follower controls the opening of the hinges during insertion and extraction Detector support transfers to kinematic dock when positioned at the operating location pixel support hinges cam followers and linear cam slide rails sliding carriage Reason for no bottom Beam Pipe support… kinematic dock 6

7. Engineering Division Engineering Installation 7 Requires that all of delivery system, and kinematic mounts are available by then (half if only 2 sectors installed) New Beam Pipe, ISC, Articulated rails/D-tube, and Modified East Cone—See later slides for what these are Production Electronics and additional sector assemblies can lag

8. Engineering Division IST Mechanics Status Change to liquid cooling for IST suggested, after difficulties of Air Cooling realized on Pixel cooling efforts –Affects how modules are laid out on IST stave structures Work on ATLAS Tracker Upgrade for Super-LHC in progress at LBNL and BNL for both Pixel and Strip detector local supports IST structures can benefit from these developments –Use directly the technologies and materials developed –Modify the geometry to suit IST Module Geometry IST Strip sensor and its integration with Hybrid and FE chips should be next effort –Module needs to be optimized for thermal conduction of heat into structure –Result of this integration will determine geometry of stave-like support Excerpts of work on ATLAS Upgrade staves presented in Backup Slides 8

9. Engineering Division Names of Elements New West Cone supports FGT, and is in turn supported by East Cone East Cone (retrofit), Supports also ISC (Inner Support Cylinder), which provides installation and environmental volumes for Pixels, and directly supports IST 9 SSD IST IFC NWC New Cone Structures inside of Inner Field Cage ISC Pixel East Cone

10. Engineering Division Mechanics Integration and Design Global integrating structures Overview in relation to FGT –HFT Shares support with FGT –SSD addressed, however it is an independent project… Internal HFT geometry –Pixel and IST integration and assembly sequence—includes FGT and SSD: are integrally related (our design must allow) Integration Requirements –Beampipe Integration and Requirements –Services Integration Schedule/Availability of structures tied—need to start planning manpower profile… 10

11. Engineering Division Global Integrating Structures FGT requires a new West Cone in ’09, and SSD plans to be in during the ’09 run as well New West Cone (NWC) needs to be available by ’09, but Needs East Cone (equivalent) to support it… –Proposal Following pages… NWC + old East Structure must be able to support SSD HFT requires a new East Cone, or at least a modified East Cone Aim in component definition is to allow for maximum Parallel integration –All need to be ready for insertion during an opening –Cannot tolerate much serial integration in Opening schedule… Consequently, many structures need to be available simultaneously and early enough to allow prior integration of detectors… –Need to understand schedule well to plan construction schedules –‘Need Dates’, and proximal integration schedules need to be known to target structure availability milestones for production schedule –More on this throughout… 11

12. Engineering Division Cut Apart Current Cones August 2009 Cut Carbon Elliptical Beams avoiding Al Insert Old East Cone and most of Beams to be reused to support New West Cone for first FGT run (no Pixels or IST, but allow SSD to be installed Old West cone refurbished into New East Cone in Berkeley Aim is to make a design compatible for ‘quick’ swap of east structures (bolted) 12 Send to BerkeleyKeep at Brookhaven Aluminum Bonded Into Carbon

13. Engineering Division Modify East Cone and Install with New West Cylinder View as Temporary Fix—Should be ACAP (as cheap as possible) –Supports end of New West Cone/FGT –Replicates Old Beam Pipe Interfaces –Includes SSD if required –Only for summer ’09 to ’10 (DATES?) Wholly Machined/Bonded Solution –Tooling to locate Buck Plate while bonding is required… Should be possible in ~2wk timeframe… –Need to do this during same opening that FGT is installed –Components and tooling must be ready beforehand! Buck Plate aimed for Easy Swap of replacement Some Tooling Required… ~1.5m 13 SSD Mounts Included Old SSD mounts Part of FGT Budget?

14. Engineering Division Replacement Consistent with IST/Pixel Installation Should Be Same Length New East Cone with Cylindrical Shell made from Old West Cone Swap in by matching Bolted Interface to New West Cone… Modification Will Take Up Length… Include SSD interface On Shell (not shown…) 14 Shell to replace Beams

15. Engineering Division Layout of Insertable Cone Structures in IFC Note that SSD and FGT will likely be installed before internal system (IST/PXL) is available –If SSD not installed could pre-integrate on outside of New East Cone prior to opening… Aim is for quick integration of these during any one opening –As much pre-integration as possible prior to opening is a priority ISC with Beam Pipe and IST are inserted first into Cone Structure (with FGT and SSD installed) ISC needs to be removed to install IST if it lags pixels 15 Gap for ISC services Required thru ISC support off of NCS SSD IST -15C(?) Room Temp Pixels Cartooned in

16. Engineering Division ISC Integrated with IST and Beam Pipe Smaller cylinder has both IST and Beam pipe supports Integrated Integrate IST first on Small Cylinder where appropriate (MIT or BNL) Insert Beampipe and fix on mounts –Requires long bench to support Beam Pipe until full load transfer to ISC –Right hand side eventually cantilevered by this structure for insertion into Cone Structure Add large cylinder, transfer Beampipe to top support –no permanent bottom support—interferes with Pixel insertion rails/tooling) Dress IST Services on outside of large Cylinder 16 Separate Cylinders (bolted Interface) Asymmetric Beampipe Allows for Articulation of Pixels to small Radius prior to insertion into smaller cylinder Double support provides moment constraint for insertion Include Service Penetration/Seal Insertion Rails

17. Engineering Division 17 Assembly Sequence Aims at Parallel Integration PXL PXL Insertion (after Cone in STAR) ISC IST IST Integration Beam Pipe Integration FGT SSD NCS SSD Integration FGT Integration (COMPLETED PRIOR) PXL IS Insertion (includes BP and IST) ISC IST Insertion into STAR SSD Integration Done independently (as required) ’09-10? Intention to place PXL engineering ‘patch’ system as early as possible— preceding IST Installation IST/ISC follows FGT by ~1yr Pixel Compatible BP ‘should’ be ready…

18. Engineering Division Design Requirements and Interfaces Previous slides showed only how we intend to assemble the detector in a ‘Big Picture’ sense… –Important to define this ‘Top Down’ as this more clearly defines need dates for individual structures… Assembly sequence also defines what is supported where and by what component(s) –Top Down approach makes support chains clear –Presents a clear inroad to define structural requirements of each deliverable in a tiered fashion In defining these, we must also apply auxiliary constraints, e.g. service volumes/routing, and Environmental requirements –Distinct non-interpenetrating volumes must be defined (what can be shared, and what cannot) –Cross-Sections, gaps, and penetrations must be imposed (and enforced) for servicing various detectors Auxiliary constraints will impose additional requirements on structures All usually detract from Ideal Performance, so best to identify early 18

19. Engineering Division Beam Pipe Interfaces Beam Pipe is integrated structurally with ISC (note IST also installed prior to insertion in Cone Structure) Integrated bake-out jackets required in FGT volume (no space for insertable jackets)—propose to replicate on East Side –See ATLAS Beampipe as example of integrated Bake Out heaters Removable bake-out jacket installed in place of Pixels during bake –Pixels can’t take bake-out temperatures Trim heaters are a separate circuit of integrated bake-out jacket— used during operation to prevent condensation on Beam Pipe 19 Moment Supports Removable Bake-Out Jacket Integrated Bake-Out Jackets External Support to IFC Far side of FGT (or to West Cone) Trim Heater (and Bake-Out) Supports to ISC (Bottom after Pixel Install) -15C inside of ISC

20. Engineering Division Service Cross-Sections and Patch Panels Services Span Environmental Volumes –Propose to make all penetrations of these volumes with Bulkhead connections Sealing to cables, tubes, makes all services one non-modular unit upon sealing –May interfere with assembly sequences or maintenance Service Density of HFT Pixels and IST are low, ATLAS Pixels has ~10X the services in the same radius –HFT can likely use only the end plate area to make all penetrations… 20

21. Engineering Division Status of Structural Design efforts Global Structures like the Cones and ISC are primarily at the layout level –No detailed models or analysis, only sizing and envelope CAD models exist –Need to engage Beam Pipe engineer IST undergoing changes to layout and cooling scheme –Design direction exists, working on module layouts Pixels most advanced –CAD models of sufficient detail for FE Analysis exist and exercised –Several iterations of analysis complete, sufficient to verify design direction and identify prototype effort Detailed work on mechanical requirements and interfaces ongoing for global structures 21

22. Engineering Division Tiered Mechanical Requirements Maximize Block Elements that need to be aligned (tracks) with 6DOF –Minimize changes (within cost limits) between surveyed and installed detector elemenst Target each tolerance limit locally, and tie to detector resolution –Pixel internal tied to 20  pixel to pixel ‘Box Tolerance’, e.g. 6  RMS X 12 ½ –Pixel to IST location tied to IST (or SSD), whatever is tighter Geometric requirements are aimed at knowing Detector positions after a survey –Fabrication tolerances are dominated by mechanical interference and guaranteed overlap not resolution –Resolution drives stability requirements within and between detectors Above paradigm used to attribute stability and tolerance budgets across Local and Global structures—all tied to physics performance Operating Stability will be the driving requirement, but includes also any change from survey geometry prior to installation –Vibration environment measured, method in backup slides to bound problem –Hygro-thermal deflections yield well to analysis and can be predicted from prototype/FEA iteration Cooling and Operational temperature fold into above—represent gradients, and impose isolation requirements on Global Structures 22

23. Engineering Division BACKUP SLIDES ATLAS UPGRADE details ARES Calculations on Pixel 23

24. Engineering Division Modify Old West Cone at LBNL Cut off embedded Aluminum inserts and add Flange Cut-Length optimized for ISC and Cylinder that will replace current Beams… Will Become new East Cone—aim for quick swap of temp structure Trim Bolt Flange

25. Engineering Division Flange on New East Cone (Detail) Auxiliary Goal of Flange Two-Fold –New Interface to West Cone (remove old BP Interface Plate and beams) –Use Same Tool for large cylinder of IST and Intra-Cone Cylinder (SSD Support Shell) Need to understand if this effort is cheaper than using tooling for NWC (available as NWC extant for FGT installation) However—this represents current ‘baseline’ Gap or Standoffs for IST Services Needed R220-225ISC Bolt PCD same as ‘Buck-Plate’

26. Engineering Division Single DOF SHO used as model Frequency can be approximated from peak gravity sag of FEA models (under-predicts for most structures) Other approximations can be extrapolated, using root(k/m)  RMS is a strong function of the first fundamental frequency Q is fixed based on material –Typical Q for CFRP is ~10, i.e. 5% damping factor (need to measure) –Effective Q increases for increasing modes (more material involved in deflection)—f 1 dominates PSD (Power Spectral Density) in units of g 2 /Hz is known for STAR –g 2 /Hz ~power/cycle/unit-mass, can use to tie to various phenomena, e.g. air-flows Useful tool to direct optimization Thanks to Bill Miller for introducing this method 26 m mg  * * * Least offensive clip art for ‘Spring’ mg=k  subbed into frequency eq.

27. Engineering Division Stiffness Criterion 27 6m RMS Requirement Heavy MFG PSD* 1 X 10 -6 g 2 /Hz Light MFG PSD* 1 X 10 -7 g 2 /Hz Frequency Target Frequency Range * Source: Newport Optical Table design appendix

28. Engineering Division Methodology SDOF SHO is typically less stiff than a real structure, i.e. a real structure with given gravity sag has higher F 0 than this model predicts –Adds conservatism PSD for STAR is not broadband, so using previous figure to set requirements is conservative –Final design would use exact PSD Heuristic approximation of allowed gravity sag gives quick direction to improve designs—particularly for global supports –Assuming rotationally symmetric geometry, also bounds lateral modes Higher order modes typically unimportant, though useful to verify accuracy of models when correlating with measurements of real structures (prototypes) 28

29. Engineering Division IST versus ATU—differing goals ATU has different thermal requirements –For ATU, sensor temperature is more important than FE temperature (radiation damage is higher) –Energy density is much higher for ATU and the coolant temperature much lower (-35C or lower) Strip prototype thermal image shows that thermal path to FE chips for a strip sensor is important Despite requirement differences, the Stave structure performs similar enough tasks –Stable support which rejects influence of distorting forces –A cold surface which extracts heat from modules –Modular building approach Thermal and structural approaches are similar, and IST requirements are less challenging IST needs to optimize Module to meet thermal goals, and integration techniques 29

30. Engineering Division 30 ATU Pixel Stave Prototype - III Final assembly(foam+fiber halves glued together around tube) Heaters on YSH-70 side only for first measurements Platinum-on-silicon heater in middle to simulate pixel module and copper-kapton heaters on either side to minimize end effects. Silicon heater represents accurately the Heat load of a sensor allowing direct IR measurement of temperature 6.9 mm 24 mm Foam 260mg/cm 2 (exc. Pipe) => 130mg/cm 2 for

31. Engineering Division 31 ATU (SLHC) Pixel Stave Prototype - I Tube with CGL7018 YSH-70 and K13D2U glued to foam Tube in foam with CGL7018

32. Engineering Division 32 ATLAS Pixel Stave Prototype Development Thermally conducting foam obtained from Allcomp, Inc –0.18 g/cc as delivered –Thermal conductivity not measured (yet) Small prototype (20 cm long and about 2.4 cm wide) made – see photos previous page –Small aluminum tube(2.9mm OD and 2.3mm ID) used to simulate about what might be used for CO2 at SLHC –  needs to be optimized for IST Flow requirements –Foam machined (easy) to shape and with groove for tube –CGL7018 used to couple tube to foam –Hysol 9396 loaded with Boron Nitride (30% by weight) used to couple facings to foam One facing is YSH70 cloth, 140 microns thick Second facing is K13D2U 4-ly laminate 300 microns thick (90- 0-0-90 orientation) Estimate of %X 0 for IST ~0.75% X 0 with coolant (structure only)

33. Engineering Division 33 Thermal Performance IR camera used Water coolant at 1.0 l/min at 20C. Vary power level in silicon heater And separately in copper-kapton heaters to about match Power/Area LabelEmisBGAveSDMaxMinUnit A10.9519.027.410.6528.425.9C A20.9519.027.360.8028.423.8C T in boxes

34. Engineering Division 34 Preliminary Thermal Performance IST has a target dissipation of 0.065W/cm 2 FE-I4 goal FE-I3 normal Max. spec * * * Includes sensors & power conv. But not cables. IST Goal

35. Engineering Division 35 ATU Nominal Design – Short Strips Bus cable Hybrids Coolant tube structure Carbon honeycomb or foam Carbon fiber facing Readout IC’s 10cm detectors, each with 4 rows of chips on hybrids Hybrids glued to detectors and this assembly glued to mechanical/cooling support ~ 1 meter Note that the Pixel design has a different heat path than a Strip Module—the following is more representative of the IST (except this is double sided) ATU Super-Staves are double sided—sensors on each side…

36. Engineering Division 36 Wider Prototype for Strips, goal now ~4cm 1m prototype 2.8mm tube/foam 4.9 mm tube/foam Flattened tube Note prototype width is about 7cm – set in 2006 POCO foam: about 0.5 g/cc thermally conducting carbon foam Facings are K13D2U fiber laminates Carbon honeycomb All tubes aluminum

37. Engineering Division 37 Thermal Prototypes—Strips with Hybrids Water at about 20C IR images Before and after thermal cycling between 20C and -35C 50 times Bus cable Alumina hybrids Heaters 0.3mm silicon 3.3 W/hybrid(0.55 W/chip) No Power

38. Engineering Division Sector/ladder design—what was analyzed thinned MAPS chips 2 cm by 2 cm, 50 µm thick multilayer aluminum kapton flex circuit cable for signal and power thin carbon composite substrate carbon composite support beam 38 Heat loads defined by region on MAPS chips and End of Ladder electronics Ladder Overhang important

39. Engineering Division 39 Fins versus Ducted flow (improved Heat Transfer)

40. Engineering Division 40 Results from above—Fins Win

41. Engineering Division Internal Fins base lined for further Analysis Flow rates of 4-8m/s used—produces flow in the 50CFM range, which seems reasonable Fins required to improve heat transfer area, given Heat Transfer coefficients for air of this velocity Fins also improve some of the structural deformation modes, but add material –Don’t know how to build fins yet –Have not modeled air flow, so cooling rates likely optimistic Fin size and position likely needs further optimization –Need to build prototypes to guide this 41

42. Engineering Division For flow on inside only, most recent result 42

43. Engineering Division Displacement from imposed Thermal Distribution 43 No Silicon

44. Engineering Division Load Transfer from insertion table to Mounts 44

45. Engineering Division Hinge analysis—Mount Engagement Forces 15kgf (~150N) applied at end of magenta links (rigid elements) Stresses are low (from an alternate analysis not shown) Deflections are shown on Y axis only (note reversal) Max Deflection is 0.14mm (negative Y) Aim is to show that Hinge, under insertion load will hold kinematic mounts within appropriate acceptance window of Kinematic Mounts Analysis shows this is currently acceptable 45 -0.14mm +0.015mm +Y Analysis of initial hinged parallelogram concept; additional concepts are also being investigated to understand if an even simpler solution is available. Analysis shows that this is viable ~0mm

46. Engineering Division Pixel D-Tube to ISC mounts 46

47. Engineering Division Pre-loaded mount and Registration 47