Walter Sondheim, FVTX Review Nov 12 th, FVTX Mechanical Status : Walter Sondheim - LANL Mechanical Project Engineer; VTX & FVTX

Walter Sondheim, FVTX Review Nov 12 th, Mechanical Design Philosophy : The Design of the FVTX structures and services have been driven by the following requirements; –High mechanical and thermal stability. –Radiation tolerance up to an integrated dose over 10 years of 300 – 500 krads in the region of the detectors and 200 krads in the region of the ROC (read-out-card). –High transparency to particles, keep the radiation length to a minimum, especially the material mass that is in the acceptance. –Silicon modules to be maintained at room temperature or slightly lower, sensor electronics has low susceptibility to radiation damage. –Very low maintenance over 10 year expected lifetime. –High granularity of the services to increase the reliability of the operation. –Modular Assembly.

Walter Sondheim, FVTX Review Nov 12 th, VTX-FVTX Half Assembly for Introduction: Two half FVTX detectors Beryllium beam-pipe, mm OD X mm long VTX detector, 4 layers; inner 2 pixels, outer two strip-pixel sensors Big Wheel region; read-out electronics for VTX&FVTX Support structure and isolation mounts attached to central magnet

Walter Sondheim, FVTX Review Nov 12 th, Sensor Module: Two variations for stations 2 & 3, upstream and downstream: UpstreamDownstream POCO graphite support block with pin hole for alignment, screw hole for mounting PEEK support block with pin hole for alignment and screw hole for mounting Graphite back- plane 1.56 mm, K13C2U carbon fiber, Cyanate Ester resin, fabrication at LBNL HDI.44 mm Sensor.32 mm FPHX chips bonded to HDI Mounting screw location HDI connectors to extension cable to ROC Bonding of FPHX chips to HDI use Arclad 8026 transfer adhesive, 1 mil Bonding of silicon sensor to carbon backplane Arclad 8026 and Tra-bond 2902 silver epoxy

Walter Sondheim, FVTX Review Nov 12 th, Half-Station sub-assembly, stations 2, 3 or 4: Mounting and alignment pins in tabs, 3 per station half disk Thermally conductive block to transfer heat from wedge to support panel Nylon mounting screw – (phillips head) Graphite faced support panel Four layers of 15 degree wedges, 2 layers on each side of support panel Each wedge staggered in Z, 15 degrees between wedges on one side, upstream to downstream sides of panel offset by 7.5 degrees – hermetic in phi. Each silicon sensor covers 7.5 degrees in phi.

Walter Sondheim, FVTX Review Nov 12 th, Support Panel Construction: Hose barb PEEK Insert for screws and pins - PEEK Wedge locating pin Mounting tab GFRP face sheet,.25 mm Core – foam, 4.76 mmCore insert, pins and screws, PEEK Cooling channel, PEEK GFRP face sheet,.25 mm Fabrication of disk assembly will take place at LBNL composite shop Holes for survey flag along edge

Walter Sondheim, FVTX Review Nov 12 th, Half Cage Assembly with Liquid Cooling Circuit: Each station is cooled in parallel with the other stations. Inlet temperature 0 – 10 degrees C, delivery pressure 5 psi Delta-T per ½ station 1.8 degrees C, delta p.4 psi Coolant 3M Novec 7200 Inlets Outlets Novec 7200: Boiling point 76 degree C Melting point -138 degree C Vapor pressure degrees C Neutron irradiation study at LANL’s WNR facility – total dose 6.7 X 10**11 n/cm**2, nominal energy 800 Mev. Samples were sent to 3M for analysis of free Flouride, no indication of significant degredation.

Walter Sondheim, FVTX Review Nov 12 th, FVTX Cage: Cage design uses CN60 carbon fabric with a EX1515 resin. FEA analysis indicates very rigid structure < 25. microns. Blocks and flanges POCO graphite ACF- 100Q. Note: the mounting blocks for the 4 stations will be clocked in 1 degree increments. Each FVTX interfaces directly with the VTX space-frame. For scale: 400. mm in diameter, 187. mm in length. Penetrations in shell for survey/alignment flags Fabrication will take place at LBNL composite shop.

Walter Sondheim, FVTX Review Nov 12 th, Coolant to FPHX Chips Thermal Path – 2007 review – current changes: Use Simple Correlations to Evaluate –Pressure drops –Temperature drop from fluid to cooling tube Approximate temperatures with 10°C coolant flowing at Re~10,000 (0.76mm K13CU backplane, 50μm Nickel tube, 0.2 W/mK epoxy, 0.75 W/mK silicone) 2008 Changes to Wedge: FPHX readout chip power increased 100 to 600 micro-watts per chip. Rerun thermal model and FEA analysis over next month Thicker 2X Thicker 2.5X Channel POCO graphite Arclad 8026 transfer adhesive Foam PEEK

Walter Sondheim, FVTX Review Nov 12 th, Large Station and Cage-Level Modeling: Fundamental Vibration ModeDistortion due to Cooling (assembled at room temperature) Max deflection ~ 21μm Max deflection within active area ~ 8μm 138Hz

Walter Sondheim, FVTX Review Nov 12 th, Measurement of Central magnet vibration; Vibration Level Threshold 1*E-8 g2/Hz Accelerometer Noise Floor 1*E-11 g2/Hz Peak Measured Vibration 1.2*E-9 g2/Hz Vibration measurements were made on the Central magnet pole tips to see if mounting the VTX-FVTX vertex detectors off the pole tips would induce unwanted vibrations to the operation of this detector system. A comparison of the vibration levels measured and the threshold levels calculated – showed that the peak vibration levels are 10X lower than the threshold value. The measurements made in the PHEINX IR were successful at collecting sufficient data to conclude that the vibration levels on the support rails would not adversely affect the performance of the vertex detector system.

Walter Sondheim, FVTX Review Nov 12 th, Two Independent Halves: “Big Wheel” cooling plate with coolant channel along perimeter, 3. mm Aluminum ROC cards, 38. watts/card Gas seal between layers Wedge readout extension cables This half FVTX assembly is stand alone, can be tested independently of the rest of the detector in a lab.

Walter Sondheim, FVTX Review Nov 12 th, Model heat transfer in lab: Model heat transfer in wedge assembly Model heat transfer from ROC cards to cooling plate Watlow heater 75 watt

Walter Sondheim, FVTX Review Nov 12 th, Summary: WBS 1.6 Mechanics – Schedule Dates & Manpower WBS 1.610/21/2005 – 9/29/2009 –WBS Specifications 10/21/2005 – 2/9/2006 –WBS Support Structure Cage 4/1/2007 – 12/25/2009 –WBS Wedge Backplane4/11/2008 – 6/19/2009 –WBS Support Disk 1/4/2007 – 8/28/2009 –WBS Alignment and Assembly 8/1/2008 – 3/5/2009 Manpower –1 engineers –1 physicist liaison –HYTEC: 1 Engineer 1 Designer