1. LST Mechanical Design Review Utility Routing, Cableways & Crate Locations Peter Kim October 21, 2003

2. P.Kim2 OVERVIEW SPACE ISSUES –Where Do All the Cables Go? –Cable Routing inside the Sextant –Cable Routing Around the Detector –Cable Routing to Outside Shielding Wall WITHOUT DISTURBING OTHER COMPONENTS Some RPC Infrastructure Remains –Top/Bottom Sextants installed in 2004, Side Sextants in 2005 –Cylindrical RPC & ENDCAP RPC Operational after 2005

3. October 21, 2003P.Kim3 Current IFR/RPC System High Voltage –CAEN HV Supply in Elec. Hut outside the Shielding Wall –HV Distribution Boxes positioned around BABAR Detector –8 kV HV Cables to RPC Modules behind the Corner Plates Gas System –Gas Manifold/Bubblers/Flowmeters in Racks above BABAR –Teflon/Polyflo Tubes feed RPC Modules behind the Corner Plates Signal Readout –Preamps on RPC Modules –Twisted Pair Flat Ribbon Cable carries Signal to FEC in Racks around BABAR Detector; Processed Signals go to DAQ via Optical Fibers

4. October 21, 2003P.Kim4 RPC HV Cable Routing Gas Supply HV Cables Drawing from R. Principe Shielding Wall

5. October 21, 2003P.Kim5 BABAR CABLE TRAYS LST will use North Tray TRAYS are Busy, but Space available for LST HV/Gas Lines

6. October 21, 2003P.Kim6 RPC Gas Tubes TEFLON Gas Supply Tubes TEFLON / POLYFLO Connections Backward Side Front Side TEFLON POLYFLO

7. October 21, 2003P.Kim7 A Sextant full of RPC From R. Boyces Talk this Morning

8. October 21, 2003P.Kim8 LST High Voltage System HV Distribution (Baseline Design) –HV Supply located above Electronic Hut outside Shielding Wall –One HV Cable (10-wire or 20-wire Kerpen) for each LST Module –Total of 564 Cables (94 Cables in each Sextant) –No Distribution Boxes near BABAR: Long Cables (25-40 m) from HV Supply to LST Modules Cable Trays & Cableways –HV Cables need to be Separated from Other Supply Lines –New Cable Tray under the Shielding Wall –New Cableways to run HV Cables Around BABAR Detector Inside Each Sextant –Top/Bottom Sextants: Use Open Space Either Side of CENTER PLATE –Side Sextants: Use existing RPC Signal Cable Box in the Middle

9. October 21, 2003P.Kim9 High Voltage Supply BABAR Detector Electronic Hut RPC HV Supply LST HV Supply

10. October 21, 2003P.Kim10 BABAR Viewed From South Center Plate Corner Plate Side Plate Removed

11. October 21, 2003P.Kim11 Closeup View of Side Sextant Side Plate Goes Back in Here

12. October 21, 2003P.Kim12 Open Box Signal Readout Cable Box (2 Wide, 5 Deep) Signal Readout Cable Box (2 Wide, 5 Deep) Space Available for LST HV/Gas Lines (6 Wide, 5 Deep)

13. October 21, 2003P.Kim13 High Voltage Cable KERPEN 6 kV HV Cable Zero Halogen, Frame Retardant Polymer Sheath Diameter: 9.1 mm for 10-conductors 10.7 mm for 20-conductors Minimum Bending Radius = 6 x Diameter Tinned copper, Flexible stranded Conductors (0.16 mm diameter)

14. October 21, 2003P.Kim14 LST Gas System Gas Distribution –Reuse Rack space on Top of BABAR, currently occupied by RPC Crates –New Gas Manifolds, but Reuse RPC Bubblers/Flow meters –LST Gas is NON-FLAMMABLE Reuse RPC Teflon Tubes –Need to install 60 more lines (228 for RPC; 288 for LST) –RPC Tubes going to the Front Side need to be Rerouted (LST Gas Tubes go to Backward Side only) Polyflo Tubing –Teflon/Polyflo Connections –Two Bundles of 24 Polyflo Cables (Input/Output Lines) enter Sextants in the Middle

15. October 21, 2003P.Kim15 HV-GAS Supply for LST

16. October 21, 2003P.Kim16 LST Electronics Readout BASELINE DESIGN –Z-Strip Signal Read out from the Back Side 1152 Channels per Sextant –Phi Signal Read out from the Front Side 758 Channels per Sextant –AMPHENOL Twisted/Flat Readout Cable –Preamps on FEC, Not on the LST Module –7 Crates for Z Signals and 6 Crates for Phi Signals –Output Digital Signal to DAQ via Optical Fibers CRATE Features – VME Standard 6U High (26.5 cm); 55 cm Wide, 55 cm Deep –7 Crates for Z Signals and 6 Crates for Phi Signals –All Input/Output Cables are Connected from the Front

17. October 21, 2003P.Kim17 Amphenol Readout Cable MicroribbonTwitst/Flat Cable 17 Twisted Pairs Shielded & Jacketed Diameter at Round Section: 0.75 cm 48 Phi Cables / Sextant 72 Z Cables / Sextant Enough Room in Two 5 cm x 12 cm Cable Boxes / Sextant

18. October 21, 2003P.Kim18 Examples of Conduits for Phi Signal Readout

19. October 21, 2003P.Kim19 Rack Locations Keep the Racks Close to LST Modules –Deterioration of Raw Signal over Distance –Higher Background Noise Pick Up over Distance Space Considerations –Allow Access to Other Parts of BABAR Detector, Endcap Doors, Earthquake Braces, etc. –Cooling Fans / Air Circulation –Removal and Insertion of FEC Cards

20. October 21, 2003P.Kim20 Electronic Rack Locations on the Forward Side Drawing from R. Principe

21. October 21, 2003P.Kim21 Electronic Rack Locations on the Backward Side

22. October 21, 2003P.Kim22 Space Check with Mockup Crates

23. October 21, 2003P.Kim23 Installation Schedule Racks & Fixtures Design, Fabraication, and Installation before July Shutdown New Cable Trays and Conduits installed while RPCs are being removed GAS Tubes and HV Cables will be laid down One Layer at a time, following LST module install schedule

24. October 21, 2003P.Kim24 SUMMARY NO SPACE PROBLEM EXPECTED UNDER BASELINE DESIGN LOTS OF WORK TO DO, BUT WILL BE ABLE TO MEET IFR INSTALL SCHEDULE FOR 2004/2005