LHCb VErtex LOcator

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LHCb VErtex LOcator

• LHCb
• Introduction
• Vertex Locator
• Design
• requirements

Beauty 99
Chris Parkes
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Why is there more matter than anti-matter in the
Universe ?

• Take a particle and turn it into its
  anti-particle and spatially invert it (CP)
• Can we tell the difference between the matter and
  the anti-matter.
• Yes! Tiny fundamental difference we want to
  make precision measurements of this tiny flaw in
  the CP mirror

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LHCb Detector
Experiment for the LHC at CERN Due to start
2007 Expected to be operational for 10-15 yrs
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Geometry
R and Phi measuring sensors
Detectors separated 6cm during injection
small overlap
10cm
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Design

• R/Phi Sensors
• 40-100um pitch
• 2nd metal readout
• 4um resolution

• Primary/ b decay Vertex reconstruction
• Stand alone Tracking
• Second Level Trigger
• Fast tracking
• Extreme Radiation Environment
• 8mm from beam,
• 1014 1 MeV n/cm2 / year

One set of half disks

• In vacuum
• Retract each fill
• Align each fill

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Vacuum Vessel
RF shield vacuum barrier
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Radiation Environment

• Including effects of walls, vessel
• High doses at tips
• (1/r2)
• n on n Silicon as base solution

Dose after 1yr
1014
station 6
1 MeV equivalent neutrons/cm2
1013

• gt1014 1 MeV neutron /cm2 equivalents per year
• We need a detector to survive gt 1015

1 2 3 4 5
6
cm
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Ideas ?

• Other materials
• Higher oxygen concentration Cz silicon
• 3D geometry