Beam background in Vertex detector

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Beam background inVertex detector

• Tohoku. Univ. T.Fujikawa

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Problems

• There is a large difference between our hit rate
  result and TESLA group one.
• Jupiter had a (little) bug.

We need to recheck hit rate and find out why
there is a difference.
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Supplement Number of fired pixel estimation
Number of fired pixel per one cluster is about
3.7.
This value will be used to estimate background
occupancy.
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Modified occupancy estimation
Assumptions

• pixel size 20micron 20micron
• one track hits 3.7 pixels
• hit rate errors are estimated by 3vn
• train is divided 20 readings

(transversal line shows occupancy 0.5, 0.2
line)
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Summary
There is a still large difference between our hit
rate result and TESLA group result. (TESLA group
result is 3.5 hits/cm2/bunch with R1 1.5cm, B
4 tesla.)
Next plan

• Find out why there is a difference between our
  result and TESLA group one.
• Estimate track error with using desirable
  detector configuration.