Alignment Class

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Alignment Class

• W. H. Bell
• University of Glasgow

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Outline

• Model for Parameterisation
• Code Overview
• Alignment class
• Member functions
• Implementation details
• Future Plans

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Generic Misalignment

• Each Detector Element (Rigid)
• Displaced
• Rotated About some pivot point

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Describing Misalignment

• Rotation
• Use Euler angles ?,?,?
• Move pivot to origin
• And Rotate
• Displacement
• Use simple vector

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Current Code Overview
DetectorElement - Contains private member
pointers to both const IGeometryInfo 
createGeometryInfo () const IAlignment createAlig
nment ()
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AlignmentInfo - Members

• Provide all IGeometryInfo member functions
• Provide access to alignment parameters
• Rotation Matrix (and as vectors)
• Pivot Vector
• Displacement Vector

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AlignmentInfo - Members
public void setDisplacement (HepVector3D)
HepVector3D getDisplacement () void setPivot
(HepPoint3D) HepPoint3D getPivot () void
setRotationMatrix (HepMatrix) HepMatrix
getRotationMatrix () void setRotationAngles
(vectorltdoublegt) vectorltdoublegt
getRotationAngles ()
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AlignmentInfo - Implementation

• Provides methods
• GeometryInfo
• Alignment param
• Contains instance of GeometryInfo

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AlignmentInfo - Inheritance

• Inherit from IGeometryInfo
• Pass pointers of IGeo.. type
• Minimal code re-writing.
• Two IGeometryInfo objects in DetectorElement
• Keep one for MC generation
• Reconstruction code use Alignment version only

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Future Plan

• Implementation AlignmentInfo
• Following agreement on class structure and
  content
• Addition of alignment information into DB.
• Write documentation and implement tests.