1. 18 November 2010 Immanuel Gfall (HEPHY Vienna) SVD IR Mechanics 7 th B2GM

2. SVD IR Mechanics 2Immanuel Gfall (HEPHY Vienna)18 November 2010 Layer Sensors/ Ladder Origamis/ Ladder LaddersLength [mm]Radius [mm]Slant Angle [°] 32 0 7/8262380 43 1 103908011.9 54 2 1451511517.2 65 3 1764514021.1 Status One Month Ago

3. SVD IR Mechanics Current Status Parameters from the table stay the same Added components that fix certain parameters Interesting concept for end ring cooling Updated isolation/support shell 3Immanuel Gfall (HEPHY Vienna)18 November 2010

4. SVD IR Mechanics End Rings Split end rings Outer 3 layers offer openings for service routing Cooling is implemented into the ring structure Material: Stainless steel End rings are glued to the support cone 4Immanuel Gfall (HEPHY Vienna)18 November 2010 Cooling Inlet Glueing Surface Cooling Inlet

5. SVD IR Mechanics Support Cone Carbon fiber reinforced plastic Supports end rings Creates service paths for PXD Houses patch panels Fixed to beam mask 5Immanuel Gfall (HEPHY Vienna)18 November 2010 Cooling Inlet Patch Panel Space Backplane Dummy

6. SVD IR Mechanics Beam Mask Provides background shielding Supports SVD Mounted to CDC 6Immanuel Gfall (HEPHY Vienna)18 November 2010 Forward Beam Mask

7. SVD IR Mechanics Support Assembly Is built around beam pipe SVD support structure is split into halves Beam mask needs to be split 7Immanuel Gfall (HEPHY Vienna)18 November 2010 Beam Mask End Rings Support Cone Patch Panel Space

8. SVD IR Mechanics Most Urgent Issues Service paths SVD space requirement PXD space requirement Beam mask space allocation Slanted vs. Straight 8Immanuel Gfall (HEPHY Vienna)18 November 2010

9. SVD IR Mechanics Current Concept PXD services outside of Mask Masks can be tightly fit around beam pipe 9Immanuel Gfall (HEPHY Vienna)18 November 2010 PXD Service Path Patch Panel Location

10. SVD IR Mechanics Service Paths Forward Region 10Immanuel Gfall (HEPHY Vienna)18 November 2010 Ribbon Cables CAD study to show if service space is available Almost straight cable paths are possible Study shows that there is still space left Shown scenario is the worst case

11. SVD IR Mechanics Space Requirement SVD 11Immanuel Gfall (HEPHY Vienna)18 November 2010

12. SVD IR Mechanics Mask Thickness Study Backward Search for areas < 10 mm Minimal thickness ~7 mm Additional 3 mm easily available 12Immanuel Gfall (HEPHY Vienna)18 November 2010

13. SVD IR Mechanics Mask Thickness Study Forward Thinnest region ~ 5mm Additional 2mm thickness is manageable Mask thickness strongly depends on beam pipe shape! 13Immanuel Gfall (HEPHY Vienna)18 November 2010

14. SVD IR Mechanics Barrel Support 14Immanuel Gfall (HEPHY Vienna)18 November 2010 SVD 2 had a carbon fiber shell to combine forward and backward support Belle 2 SVD needs thermal insulation (Airex cover) Carbon fiber – Airex sandwich Adds stiffness that protects SVD during installation Does not add more material as is present in SVD 2 Carbon Fiber SandwichCarbon Fiber Layer Airex Core

15. SVD IR Mechanics Installation Support Proposal SVD will be very heavy Suitable support for installation required “Sled” from SVD 2 not sufficient Oil drill style sliding tube for installation support 15Immanuel Gfall (HEPHY Vienna)18 November 2010 Oil Drill Style Tube Slide Support Flange SVD

16. SVD IR Mechanics Mechanical Feasibility of Slanted Design 16Immanuel Gfall (HEPHY Vienna)18 November 2010 Angle is determined by 2D cutout precisionManageable Stiffness of rib around the angled sectionSufficient Slanted ribs are shorter and have to support less weightIdeal End ring design and space allocationNo concern Beam mask thickness and space with slanted optionNot ideal Knee is reinforced by Crossply Conclusion: Plausible but…

17. SVD IR Mechanics … there are challenges 17Immanuel Gfall (HEPHY Vienna)18 November 2010 Production of ribs is difficult because of small applicable forces for clamping Rib vibrates during routing Water cutting could also lead to mechanical degradation Better rib end ring link solution Twist of sensor plane due to mechanical imperfection There are even more! Same problems for both options except for angle precision! Mask weight is an issue: between 15 kg and 25 kg!

18. SVD IR Mechanics Conclusion Simulations do not give conclusive answers if slanted or straight option is better Mechanics are difficult for either solution Mechanics do not clearly favor any solution as either solution has its drawbacks Lets find solutions for the current situation and please stop spending more time on finding a decision! Available time is limited, we need to get going!!!! 18Immanuel Gfall (HEPHY Vienna)18 November 2010