S. Tanaka (PXD mechanics session) KEK IR status S. Tanaka (PXD mechanics session)
12thB2GMDiscussion 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
Beam pipe, PXD and shield 9cm 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 <- Baseline(Start designing) Discussion of BP+PXD assembly table should start. Does the clearance between SVD and BP+PXD+HM require 1.5-2mm(OK!) on VXD assembly? Path of dry air(or Nitrogen) ? Include SVD volume? YES flow on SVDvolume will be more slow speed M.Ritter (12th B2GM)
Beam pipe status
Beam pipe preparation status TWO beam pipe(not three) will be produced (because of budget and commissioning schedule) Items Study Beam pipe design Almost done (minor change is still acceptable) Beryllium part production done Titanium part production Design has done IP Cooling OK Mechanical tolerance estimation OK (by weight, temperature stress) Crotched part production procedure Production period and cost estimation Connectivity test (Be-Ti) Connectivity test (Ti-Ta) Ridge shape optimization To be finished soon (Implementing to MC) PXD mount To be solved (space for sensor) Au plating inside IP chamber Now on preparation 5
Gold plating of IP inner pipe "Tohokaken" produced sputtering chamber for IP inner tube. The first trial of sputtering test will be adopted for dummy tubes with cupper plating process (next month).
Crotch part production Ta block Drilling inside structure Cutting by electrical discharge machining Brazing or EBW
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
Beam outlet part Ridge part(beam inlet) 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.
Outer pipe production Ti block Be pipe
IP outer pipe The brazing tool : chamber is constrained using springs. This setup had problem on horizontal constraint.
IP outer pipe
Production design Measured Design Error Concentricity parallelism
Measured data for Titanium part
Concentricity check
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. 4, 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 because of error. IP chamber production schedule may be loosened in order to validate each production process( expecting half year).
Support block for PXD 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.
Inner pipe production Drilling inside next step Ta+Ti by HIP Ti+Ta by HIP Be pipe Ta-Ti-Be-Ti-Ta
Connection of inner and outer pipes Ti-Ti connection by EBW
Combining each sub-parts Brazing Ti flange On this fiscal year, we will make tools for EBW and try test production to check precision Ta-Ta connection by EBW
BEAST setup
BEASTII setup BEASTII setup on vacuum scrubbing (no solenoid, no QCS)
BEAST group considering to use DOCK space on BEASTII operation PXD and SVD dock designed by Tscharlie
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
Balcony for MARCO One additional support frame to sustain MARCO weight
Schedule (IR mechanics) 2012 (preparation for VXD mock-up) From the end of 2012 Starting VXD mock-up assembly Mechanics check -> installation test , Cooling test Beam pipe production(for BEASTII) Freezing the mechanics design (including cooling system, cabling, monitors) 2013 (final VXD design) Beam pipe production 2014 SVD Ladder mount start (SVD) (2014 Sep.) End of 2014 -> BEASTII 2015 Starting VXD assembly(Aug-Sep) (CR test ) and installation 26
Thanks
Other subjects discussed on IR community
SuperKEKB beam energy @12GeV Beam energy correlation @ 12 GeV Power supply of QC1 is restricted the Beam energy balance
Beam pipe offset for LER around QCS
Weakening corrector dipoles of QC1/2 by vertically shifting the IP off axis LER Arc x +0.104 mm IP -1.400 mm 2012/8/6の資料 Belle-II solenoid axis /ldata/SuperKEKB/Lattice/Developer/LER/sler_1672_3_f.sad K.Oide
Weakening corrector dipoles of QC1/2 by vertically shifting the IP off axis Proposal x IP QC1P, QC2P -1 mm LER Arc ? mm Belle-II solenoid axis QC1E, QC2E /ldata/SuperKEKB/Lattice/Developer/LER/sler_1672_3_f.sad K.Oide
This shift will be allocated around bellows pipe Y. Ohnishi
Reinforcement of QCS stage (to reduce vibration of QCS) H.Yamaoka (K.Kanazawa)
QCS support bridge 20m Fixed Material Concrete E=30GPa Density=2.3 Weight of Concrete shield 300tons QCS support bridge Weight of magnets 20tons 20m Fixed Material Concrete E=30GPa Density=2.3 Damping= 2% Concrete shield 300 tons KEKB floor B4 floor
2012 1985
give to raise a characteristic value. (target value>100Hz) Response of QCS tip area for 2 kind of vibration from floor(Vertical) Input(two pattern) 床振動に対するここでのP.S.D.応答の計算 P.S.D Integrated Amplitude becomes below half if vibration by a KEKB floor is the same level as B4 floor. Resonance with QCS is avoided by strengthening bridge construction which give to raise a characteristic value. (target value>100Hz)
Reinforcement of QCS stage Fixed 20m Now New structure:design is ongoing Adding shield: 300tons QCS magnet:20tons 1.溝を埋めた 2. (例)Adding beam 鋼製 ロ500x500
Response of KEKBfloor for vibration from B4 floor((Vertical) Pos.2 Pos.1 Without With B4
Without reinforcement With 28Hz 33Hz 51Hz 58Hz 71Hz 79Hz
Proposal of the photon scattering measurement on a Au coated surface Ken-ichi Kanazawa Takuya Ishibashi
Motivation Design of the central beam pipe in the Belle II detector of Super KEKB The central beryllium tube is coated with Au to stop photons with energy less than 10 keV. How photons scatter on Au coated surface? The inner surface of the pipe for the incoming beam has ridges to keep scattered photon on the surface from hitting the central beryllium pipe. The problem of the edge scattering. Ideal boundary Scattered photon Unwanted photons due to the edge scattering Incoming photon Ridge
Experiment Measure the spatial distribution of scattered photon from the flat surface. If possible quantitatively. 5 degree Incoming 9 keV photon Measure photons originate from the edge scattering Are there any photons in this region? If possible quantitatively. Incoming 9 keV photon