Research on a Next Generation Vertex Detector

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Research on a Next Generation Vertex Detector

• Develop new vertex technology to measure charmed
  quarks
• Do sufficient R D so that we can prepare a
  proposal for a complete detector inside STAR.
• Technology suitable for LHC and the Linear
  Collider

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Problems
Expected Position of D0

• Most charm mesons decay within 100 µ of
  interaction. Need high accuracy and very thin
  detector.
• SLD CCD vertex detector - subject to radiation
  damage - too thick too slow to read out.
• APS (active pixel sensor) technology in infancy.
  Only one group doing tests.
• No R D on our specific requirements.
• Simulation of current technology - 250,000 events.

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Solution
Simulation (250,000 events)

• Show CMOS APS technology can work.
• Develop fast method for reading data (zero
  suppression).
• Develop mechanical support structures for 40 µ
  thick CMOS chips. Achieve mechanical tolerances.
• Explore options to make a thinner and smaller
  diameter beam pipe.
• Simulation of new technology

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First Test Results
No Source
Sr90
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First test results
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First test results
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First tests
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First events