Czochralski Silicon initial test beam results

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Czochralski Silicon initial test beam results

• Alison Bates
• The University of Glasgow
• Tremendous thanks to
• Paula Collins, Chris Parkes, John Kennedy, Juan
  Palacios, Doris Eckstein, Tjeerd Ketel Igor
  Stavitski
• LHCb UK Meeting 9th July 2003

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Overview

• Czochralski silicon introduction
• Detector description
• 2002 test beam
• Detector irradiation
• 2003 test beam -
• Successful data read out
• Quick 1st look at radiation hardness

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Czochralski Silicon

• Single crystal pulled out of melt (High
  resistivity available)
• Oxygen content
• Standard silicon 1e15cm-3
• DOFZ silicon 1e17cm-3
• Cz silicon 1e18cm-3
• Oxygen thought to increase radiation hardness

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Test beam detector

• Courtesy of Jaakko Harkonen
• Strip detector
• Pitch of 50 microns
• p on n Czochralski material
• Area read out 6.1 x 1.92 cm
• Strips run along x axis (6.1 cm)
• 3 SCTA chips for readout

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2002 Test Beam Czochralski detector

• Test beam of 120 GeV/c muon pions
• Nice clear signals from detector

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Irradiations May 2003

• PS CERN- 24GeV protons
• Already bonded gt tricky mounting!
• From annealing studies, expected Vdep for DOFZ
  400V
• Irradiation Profile

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June 2003 Test Beam-initial look at results
167V Bias shown
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Results(besides successful test beam data
taking!)

• S/N cut 6

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Conclusions

• None yet!.Detailed analysis just starting!
• Even at 5 years of LHC radiation environment
  still getting reconstructed clusters.
• Too early to conclude, but standard silicon would
  not deplete until 1400V
• Looks hopeful!