# Presentation: 410684

## Pixel Insertable Layouts

- September  2000

## Overview of Insertable-Layout Study

- Assumptions
- Attempt to keep basic mechanical concepts of staves, sectors and global support frame but scale dimensions.
- No thermal or EMI barriers in pixel system
- But must keep B-layer clamshelled=>support shell for this
- Single insertable system
- Compare with reduced layout - repeated on next pages.
- Insertable-layout drivers/assumptions
- Keep B-layer at same radius, rapidity coverage => stave length
- Make barrel layers same length.
- Current module size and same for barrel and disks
- Vary disk outer radii by looking at 10,9 and 8 sector disks.
- First disk no closer than 495 mm in Z
- Assume pixel envelope scales with disk outer radius

## Current Baseline Layout

## Proposed Reduced Layout

## Reduced Layout - Barrel End View

## Reduced Layout - Side View

## Reduced Layout Rapidity Coverage Z=0

## Reduced Layout Rapidity Coverage Z=11cm

## Reduced Layout Two-Hit-Fallback Options

- Three two-hit fall back options are(in likely order of decreasing performance but increasing ease of the schedule)
- Option 1	Layer 2 + 2x3 disks + B-layer1
- Option2	2x2 disks + B-layer2 and B-layer1
- Option 3	Only B-layer2 and B-layer1
- The number of modules for these are given on the tables on the next pages and summarized below. The rapidity coverage can be determined from the previous plots.

## Two-Hit Option 1

## Two-Hit Option 2

- Could also remove disks at 700.

## Two-Hit Option 3

## Two-Hit Insertable Layouts

- Different two hit layouts follow for different number of disk sectors.

## 10 Sector Disks

## 10 Sector Coverage Z=0

## 10 Sector Coverage Z=11cm

## 9 Sector Disks

## 9 Sector Coverage Z=0

## 9 Sector Coverage Z=11 cm

## 8 Sector Disks

## 8 Sector Coverage Z=0

## 8 Sector Coverage Z=11cm

## Radial Envelopes

- For the moment assume radial envelope scales with disk outer radius then
- Current(11 sector) = 254 mm
- 10 sector = 243
- 9 sector = 232
- 8 sector = 221
- Need more detailed services envelope to get better estimate, including possibility of services from one end “doubling back” in case all services exit from one side.
- Note smaller sectors have larger dead region per disk.
- 11 sector is 0.6%, 10 sector is 1.2%, 9 sector is 2.3%, 8 sector is 3.8%
- Since overlap in some cases, these are upper limits.

## 3 Hit 8-Sector Layout

## Coverage Z=0

## Coverage Z=11cm

## 3 Hit, 8 Sector Layout Comments

- Layer 1 and layer 2 too close together? Cannot reduce radius of layer 1, B-layer shell.
- Assuming frame size scales with outer radius/envelope, then barrel services per octant increases by about 5% compared to baseline services layout. If linear, this is about 1mm in barrel services depth.
- Disk services per octant nominally reduced by about 15%, but need to take into account quantization and tube diameters.
- There are small holes in acceptance(don’t have number).
- Current estimate is that 1500mm2 is need for power/optical connection per half-stave or sector(PP0). Available annular space in barrel is roughly 65,000 mm2 but 132,000 needed, assuming single layer. Same problem in baseline but worse as radial dimensions reduced.
- My current conclusion: envelope dimension of 221 mm cannot be decreased.