1. SVD IR mechanics status S.Tanaka SVD mechanics session

2. This report shows many kind of questions, so please discuss with SVD group and give me some answer.

3. Discussion summary (VXD designers meeting) The first priority of SVD designer is to solve 3rd layer's Hybrid cooling issue VXD mechanical mockup (check for service space or assembly procedure) –The design should be finalize at 13thB2GM(2012 Nov.) –The mock-up should be shown at 14thB2GM(2013 Mar.) –The design requirement (i.e. connection with endflange)should be summarized at next SVD/PXD meeting in Sep. –KEK mockup design and production should wait until decision The idea of ladder mount procedure is highly welcome Tanaka have to send Step file of heavy metal to VXD designers PXD ladder assembly will be done at MPI –Simple mount procedure on beam pipe =>good new for KEK group The place of PXD PP at between SVD support cone and heavy metal –discussed on SVD/PXD meeting in Sep. –which is important for new installation procedure The material selection and production procedure of SVD support structure –should decide at 14th B2GM (2013 Mar.) –Titanium option should be take care in parallel with base idea –Vienna, MPI and KEK group will start test production of CFRP cone and gluing test. (Vienna group will also study thermal stress effect) Please keep watch the status of beam pipe production. The precision of this may cause serious situation in particular for PXD mount. 12thB2GM

4. 4 2012 (preparation for VXD mock-up) 13th B2GM(2012 Nov) the mechanical mock up design (final) Beam pipe production(for BEASTII) 2013 VXD mechanical mockup will be ready (2013 Mar B2GM) Mechanics check -> installation test, service work test Beam pipe production 2014 SVD Ladder mount start (SVD) (2014 Sep.) End of 2014 -> BEASTII Beam pipe production 2015 Starting VXD assembly(Aug-Sep) (CR test ) and installation Schedule (IR mechanics)

5. SVD IR design The IR design can divided to several subjects as follow: –Beam pipe design –PXD design –SVD design –Shield design –End flange design The related subjects are –Cable route –Piping route –Monitors (Temp., Hum., Rad. and so on) –CDC design –QCS design –Endcap design VXD design

6. Beam pipe, PXD and shield Beam pipe design (outer dimension defined) PXD design has finished Shield design will finalized after SVD design PXD PP position is still open question –One option is outside of End-flange (9cm between endflange and QCS) –Another is between SVD and shield (SVD design is OK?) Discussion of assembly table should start –Does the clearance between SVD and BP+PXD+HM require 1.5-2mm on VXD assembly? Path of cold dry air(or Nitrogen) ? –Include SVD volume? –small amount dry air only for SVD? –1m/sec is OK? M.Ritter (12 th B2GM) 9cm

7. SVD End Flange Requirement: – SVD cables (KEK will test) – CO2 cooling pipe feedtrough Need idea from Imanuel – Two halve connection one idea from Immanuel – CFRP cover connction the same as SVD2? – SVD support ring connection Kohriki have idea – Dry volume? SVD reuqire lower temp.?

8. SVD ladder overlap Tsuboyama: L ３ ４．１％ (1.59 mm, 32 strips) L ４ ９．５％ (5.50 mm, 73 strips) L ５ １．６％ (0.92 mm, 12 strips) L ６ ５．９％ (3.39 mm, 44 strips) Immanuel: L3: 12% L4: 20.2% L5: 5.9% (8.5%for slant) L6: 13.8% (16%for slant) The investigation by software is required. In particular, 12 strips on L3 are sufficient for checking alignment on cosmic ray test. I want to set a strategy to solve the problem from now until time limit Comment by Ushiroda-san: This discrepancy should be solved before finalizing design.

9. Service space dependence on # of stacking SVD cables revised version with two layers(Forward) Cable set width # of SVD cables stacked PXD cablesThickness of cable set # of cable sets Service area (circumference: 769mm) 32mm 6 9.4mm*2 (data) +9.6mm (power) 11mm20984mm 712.5mm18920mm 814mm16856mm 915.5mm14792mm 1017 mm13760mm SVD cables (stacking 6-15) Larger than space PXD power cables should reduce the size! more than 20% space margin is required for smooth installation Ex: 32mm*16(sets) +(9.4mm*2+9.6mm)*10+ 12mm*5(pipes)=356+mm 15 22.5mm9630mm PXD power PXD data cable Break 9mm law KEK group will check feasibility of cabling with mockup

10. BEAST group considering to use DOCK space on BEASTII operation PXD and SVD dock designed by Tscharlie

11. PXD DOCK SPACE, phase t2 Phase t2 most constrained in terms of space. Use PXD DOCK space? Both TPCs and BGOs could easily fit in DOCK space Probably very good location for TPCs (see next page) Probably not location good for BGO  Radiative Bhabha events blocked by shielding Is there other PXD cabling space available that can be used for BGOs? S.Vahsen

12. bkup Beam pipe status will discuss on PXD session

13. 13 Beam pipe preparation status ItemsStudy Beam pipe designAlmost done (minor change is still acceptable) Beryllium part productiondone Titanium part productionDesign has done IP CoolingOK Mechanical tolerance estimationOK (by weight, temperature stress) Crotched part production procedure OK Production period and cost estimation OK Connectivity test (Be-Ti)OK Connectivity test (Ti-Ta)OK Ridge shape optimizationTo be finished soon (Implementing to MC) PXD mountTo be solved (space for sensor) Au plating inside IP chamberdiscussing with company IP beam pipe for BEASTII will be produced from this fiscal year. TWO beam pipe will be produced (because of budget and commissioning schedule)

14. Gold plating of IP inner pipe Tohokaken produced sputtering chamber for IP inner tube. The first trial of sputtering will be adopted for dummy tubes with cupper plating process (next month). Pipe support and two kind of cooling system

15. Crotch part production Test was done with small piece of Tantalum block. –The R=2 cm half-tube shape is done. –The ridge machining is done. Final production will start after decision of inner shape by BG estimation

16. – The surface is slightly rough at the deepest point. We discussed this is because the ball end milling is adapted in vertical direction. If we apply some angle to the "mill", this may not happen. – The roughness is still acceptable in view point of accelerator and vacuum. The roughness may be OK for the gold-plating. The gold plating will be done to reduce wall current heat. Decision of gold plating is made if heat is not acceptable. Thick gold plating costs a lot. Decision should be made quantitatively.

17. IP outer pipe The brazing tool : chamber is constrained using springs.

18. IP outer pipe

19. Design Error Measured parallelism Concentricity

20. Measured data for Titanium part

21. Concentricity check

22. IP outer pipe production Brazing is done. –Precision is measured. –0. Visual inspection: OK. – Outer surface: Photos. Inner surface: OK with fiber scope (no photos this time). –1. Length: 0.3 mm longer than design. This error already existed before brazing. Length change due to brazing is very limited. –2. Axis offset is 0.9 mm where target was less than 0.1 mm. 3. Parallelism is 0.2 mm where target was less than 0.1 mm. –3, Vacuum test: OK Discussion: The method of error measurement exaggerate the error. The position/orientation of the beryllium pipe against two flanges should be measured. We did not decide to use this pipe for BelleII IP chamber. IP chamber production schedule may be loosened in order to validate each production process.

23. The mechanical error of IP chamber should be compensated with PXD support block design. KEK group should provide the detail measured data of beam pipe and Tscharlie will design PXD support block. Support block for PXD