Kalman Filter Vertex Fitter

1
Kalman Filter Vertex Fitter

• Why
• Lack of tool to do vertex fit completely right
• Lack of tool to apply kinematic constraints
• Some visible drawbacks and inconsistency in
  current software
• How
• Kalman filter method
• purpose
• Improve proper time (t) resolution
• Improve t pull distribution and provide reliable
  event-by-event error
• Improve B mass resolution

• Status
• The first version to refit B particles works very
  well with long tracks and photon
• Reprocess of pi0 not done
• Need improvement with Ks
• Plan
• Release the first version
• Complete its functionality
• Get feedback from users and improve it
• Provide a second version for event selection
  after DC04
• Documentation

Contact the author if you have interest to use it
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Proper time measurements B refit lifetime fit