1. Straw man layout for ATLAS ID for SLHC
Issues to be discussed in the layout advisory group.

2. General Layout
Aim to give a preliminary layout to the Eng. Groups and establish specification and list of options for further study. E.g. for installation scenario study – need to boundary conditions – length , radius etc. that are being considering.
As a start assume the “envelopes” of the layout for preliminary studies.
For Eng. options the Working groups/R&D grouping will develop the specification and the implications of the Layout options.

3. Straw man Barrel Layouts
b-layer integrated to the beam pipe.
1 layer at R= 5 cm.
Granularity 300m x 50 m
Z 2x40 cm
Inner Layers - Pixels
2 additional layers at R=12, 18 cm
Granularity m x 50 m
Z length 2x 40 cm
Middle Layers
3 layers at R=27,38,50 cm 4 Layers (27,38,49,60)
Granularity cm x 80 m
Z length 2x100 cm
Outer Layers
2 Layers R= 70,95 cm Layers (75,95)
Granularity 9 cm x 80 m
Z length 2x190 cm

4. Straw man End-cap Layouts
Discs
7 discs
Pixel: Z= 50, 75
SS: Z= 120, layers 120,165,180
LS: Z= 210,260,320
Coverage in h
Assume coverage up to 2.5
Moderator
Need to optimize the amount of moderator on the EC face.
The main difference between the two options is if one has 3 or 4 SS layers and 6 or 7 Discs. This will depend at the end on the optimization of the overall detector.

5. ID Straw-man Layout (4 SS layers)

6. ID Straw-man Layout (4 SS layers)
3 Pixel Layers
14,32,48 f Sectors
5,12,18 R Location
4 Short strip layers
22,32,40,48 f Sectors
27,38,49,60 R Location
2 Long Strip layers
32,40 f Sectors
75,95 R Location
Moderator

7. Straw-man Options: Borated Poly – Locations and thickness.
Fixed Length Barrel Quasi “Projective” layout.
Integrated Pixel
Implications of sensor layout options
Mechanical Layout – options and questions
Barrel
Cylindrical support structure “ATLAS Like” + Discs
“Staves” + Discs
EC-Disc design
Cooling Options
Pressure, operating temperature

8. Borated Poly: Design for an integrated Luminosity of 7000 pf-1
Reduced the neutron flux/energy to minimize the damage to the electronics and sensors.
Borated Poly can be placed in:
Barrel Calorimeter Surface cm
EC Calorimeter Surface cm
Cavity in front of the Forward calorimeter cm
Ref. Radiation Task Force
Optimization:
Ian Dawson
Vince Hedberg
Mike Shupe

9. Projective vs. “fixed” length Barrel
“Fixed length”: All layers in same radial region have the same length in Z.
Projective – each layer have different length.
Projective:
Smaller Si Area
Material – needs detail engineering to comment if can be an advantage.
Fixed Length:
Easier assembly
Significant less Engineering
“Fewer” special components
e.g. fewer stave flavors.
Straw man: “Fixed Length Barrel”

10. Independent vs. Integrated Pixel
Independent : Insertion “tube” as in ATLAS.
Integrated : only “b-layer” attached to beam- pipe
Independent Pixel:
Schedule of the more complicated system is decoupled from the large area detector.
Integrated Pixel:
Less material?
Services routed at lower h
Better chance for common system
One cooling system
One Heat shield
Straw-man: b-layer with the beam pipe, 2,3rd layer integrated with the Barrel.

11. Mechanical Support
Mechanical support
Stave Option
“Drum” Option

12. “Stave” Concept
The need for High degree of Multiplexing of power, readout etc. Lead to the concept of treating a set of modules in common.
The mechanical support can be ATLAS like support (Drums) or mechanical Stave.
For each group of modules:
power, readout, grounding “fully contained”
Service design needs to be “integrated” to the mechanical and layout.
Some of these issues are independent if it is a real or “virtual” stave.
At this stage we try to propose a level of multiplexing that will allow to get an estimate for services volume and routing.
The decision on the mechanical concept will have to be discussed with the engineering team that will design the mechanical structure.

13. Drum vs. Stave Options Atlas Drum—Current Atlas
Individual Silicon Modules are mounted on drum
Stave approach to Atlas Upgrade; many modules on one long support structure (stave)
Staves supported by endrings

14. ASSYMMETRICAL SENSORS POSITION
Stave tilted to compensate for the Lorentz angle.

15. SYMMETRICAL SENSORS POSITION
Stave tangential to the
Radius.

16. Modularity – Installation Sequence
Surface Assembly of the Barrel
Assemble as much of the Barrel as possible.
In this version we assume that we can assemble part of the disks already on the surface – this needs detail Eng. Studies.
The installation sequence of ID in the pit.
Step I: Moderator and services on IWV
Step II: Barrel Surface assembly
Step III: Barrel Services (cables, pipes)
Step IV: Outer Discs
Step V: Outer Discs services
Step VI: b-layer + beam pipe

17. Surface Assembly – Step 1

18. Surface Assembly – Step 2

19. Surface Assembly – Step 3

20. Surface Assembly – Step 4

21. Surface Assembly – Step 5

22. Surface Assembly – Step 6

23. Surface Assembly – Step 7

24. Surface Assembly – Step 8

25. Ready to Transport to the Pit

26. Assembly in the pit– Step 1

27. Assembly in the pit– Step 2

28. Assembly in the pit– Step 3

29. Assembly in the pit– Step 4

30. Assembly in the pit– Step 5

31. Assembly in the pit– Step 6

32. Summary – Si Area