EC: 7 DISK concept Preliminary considerations ?

Open integration issues ATLAS UPGRADE Open integration issues Envelope for strip end-cap structure and services seems very low. C.BAULT 25 October 2012

Open integration issues ATLAS UPGRADE Open integration issues Some envelope value should be defined: Inner radius of end-cap, to have enough clearance insertion with PST C.BAULT 25 October 2012

EOS Once we accept close ground connection of two sides the next step is to combine services for two sides into one connector and one cable bundle (with common shield) This is now the baseline Next step is then to bring all GBTs (and optical links) to one side, and only bond-pad (and EOS power) on the other This is under consideration If we drop forward error correction (not needed for data (VCSELs) anyway) then there might be enough BW in future GBT to read out complete stave, so one GBT/link pair per stave only 4

Comparison to EC services Similar service arrangements (16 ducts instead of 32 service modules) In the barrel have abandoned castellated service layout – what are the consequences of EC? One EOS for two sides is likely going to be the solution for petals as well (if staves can do with one GBT, petals certainly will) Could (should) use similar components in type I service ducts, but segmentation different Cooling should be simpler (more balanced loads), loads are smaller so fewer manifolds with more branches (1 or manifolds per service duct?) Standard fibre ribbons will not be optimal for 7-disk EC Electrical harnesses could be very similar (just 14 cable bundles instead of 8) Similar interface at PP1 However, need to think about connector orientation (barrel uses cryostat chamfer) We are pushing hard throughout the tracker to reduce number and size of services Service tables have been made early summer – implications for ECs still need to be understood Some issues I see: Service supports close to petal (mechanical isolation) Insulating break in cooling pipe (where? Stress relief?) Radial envelopes (no castellation)

EC: 7D concept ...Maximum number of petals should be replaced if needed... ...Isolate services from sensors (petals)... ....Provide enough stiffness... ...Reduce the system as much as possible in radius direction...

EC: 7D substructure #1 Inner shell: “skins + (honeycomb or low density foam)” Could be also optimized with openings for mass reduction CF disks 8mm thickness “skins + honeycomb” optimized with openings “Petals attached to substructure #1 (disks)” “CF Frames to keep disks separated (provide stiffness)”

EC: 7D substructure #2 “CF Rings attached to rails... sustain service trays” “Number of CF Rings to be confirmed by FEA” “Substructure #2 is isolated from substructure #1”

EC: 7D Front view services 16 service trays concept; the total number of service-channels are 18 (the ones over the rails are split in two)

EC: 7D Front view services 16 service trays concept; the total number of service-channels are 18 (the ones over the rails are split in two)

EC: 7D Services trays Petal layout (both sides)

EC: 7D cooling pipes Petals cooling pipes should not interfere with insertion of adjacent petals (as much as possible...)

EC: 7D cabling

EC: 7D Envelope (approx. dimensions) R1020: Services R1025: Out. Ring R975: Petal R996: In. Ring R992: Gap R978: Disk R967: Silicon R384: Silicon R377: Petal R368: Gap R370: Disk R360: Inner Cylinder

EC: 7D Installing petals on sides

EC: 7D Installing services Disks allow to put petals in place using adequate petal protections All services trays should be checked out for correct operation Petals in place can now be tested

EC: 7D Installing all petals left The main goal of this system is to replace every single petal when needed (with the exception for petals under rails)

EC: 7D Petal insertion

Optional layout: difficulties end-insertion

EC: 7D Petal considerations 320mm 310mm Number of ears (just one): Petal width decreases Cabling and cooling -> unique exit EOS dimensions Upgrade (M. Stanitzki) Sensor position: No overlap between sensors mounted on petals 3mm active sensor overlap adjacent petals on same disk No overlap considered between disks Approx. 12mm Sensor-to-disk Electrical connections on both sides (disk-side)

EC: 7D Petal considerations 290 mm How much petal width can be reduced?

Conclusions New layout for EC modeled EC envelope Approximated dimensions EC constraints defined Service channels modeled (grouped in 16 trays concept at outer radius) Need to be optimized Cooling pipe minimum bending radius Fibers might need better electrical isolation New Petal modeled EOS Petal width is being reduced as EOS gets optimized (M. Stanitzki) One EOS Cabling and cooling -> unique exit along EOS Electrical connections On both petal sides

Next Steps Next steps: Cabling and piping routing FEA Petal design Interferences study with adjacent petals with service rings Service trays service tray width optimization minimum bending radius pipe length FEA Substructure #1 Obtain disk openings width Obtain inner cylinder optimized structure Rods diameter to be optimized (increase first mode frequency) Substructure #2 Obtain service rings optimized thickness Obtain number of rings needed Petals kinematic constraints on piping connections Petal design EOS EOS width optimization Bus cable Bus cable width optimization