Silicon strip layout

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Silicon strip layout
T.Galatyuk
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Outline

• Design of micro strip silicon planes
• Characteristics of strip layout
• Digitization of the hits in the STS

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Strip length calculation
x coordinate distribution in 3-d STS station
Central AuAu collision at 25 AGeV
Occupancy lt 1 Pitch 50 mm
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Total number of strip in 3 ?7 STS 2.084E06
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?
r
First layer of strips
Second layer of strips
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Occupancy
Occupancy for ? 0o
first layer
second layer
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Implementation of resolution
Charge per strip

• The total charge per hit is smeared Gaussian-like
  over the hitted strip and its next and second
  next neighbors

• A noise (poissonian with constant mean for each
  strip) is added

• Having the charge in each strip, the center of
  mass is determined as the hit position

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Resolution
dependence
Dependence ?ch on noise
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Digitization result
3-d STS
5-th STS
4-th STS
number of hits
7-th STS
6-th STS
number of zone
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Possible way to decrease the number of hits
Decrease the strip length
0.1 0.1 0.2 0.14 0.4 0.2 1.0 0.5
Strip length in 3-d STS station cm
3-d STS