CMSFrame Class Reference

CMS frame. More...

#include <ReferenceFrame.h>

Inheritance diagram for CMSFrame:

Public Member Functions
virtual ROOT::Math::XYZVector	getVertex (const ROOT::Math::XYZVector &vector) const override
	Get vertex 3-vector in cms frame.
virtual ROOT::Math::PxPyPzEVector	getMomentum (const ROOT::Math::PxPyPzEVector &vector) const override
	Get Lorentz vector in cms frame.
virtual TMatrixFSym	getMomentumErrorMatrix (const TMatrixFSym &matrix) const override
	Get Momentum error matrix in cms frame.
virtual TMatrixFSym	getVertexErrorMatrix (const TMatrixFSym &matrix) const override
	Get Vertex error matrix in cms frame.
virtual ROOT::Math::XYZVector	getVertex (const Particle *particle) const
	Wrapper for particles.
virtual ROOT::Math::PxPyPzEVector	getMomentum (const Particle *particle) const
	Wrapper for particles.
virtual TMatrixFSym	getMomentumErrorMatrix (const Particle *particle) const
	Wrapper for particles.
virtual TMatrixFSym	getVertexErrorMatrix (const Particle *particle) const
	Wrapper for particles.

Static Public Member Functions
static const ReferenceFrame &	GetCurrent ()
	Get current rest frame.

Static Private Member Functions
static void	Push (const ReferenceFrame *frame)
	Push rest frame of given particle.
static void	Pop ()
	Pop current rest frame.

Private Attributes
PCmsLabTransform	m_transform
	Lab to CMS Transform.

Static Private Attributes
static std::stack< const ReferenceFrame * >	m_reference_frames
	Stack of current rest frames.

Detailed Description

CMS frame.

Definition at line 215 of file ReferenceFrame.h.

Member Function Documentation

GetCurrent()

const ReferenceFrame & GetCurrent ( )

staticinherited

Get current rest frame.

Returns

RestFrame

Definition at line 26 of file ReferenceFrame.cc.

{
  if (m_reference_frames.empty()) {
    static LabFrame _default;
    return _default;
  } else {
    return *m_reference_frames.top();
  }
}

getMomentum() [1/2]

virtual ROOT::Math::PxPyPzEVector getMomentum ( const Particle *  particle ) const

inlinevirtualinherited

Wrapper for particles.

Parameters

particle

particle

Returns

momentum 4-vector in reference frame

Definition at line 60 of file ReferenceFrame.h.

    {
      return getMomentum(particle->get4Vector());
    }

getMomentum() [2/2]

ROOT::Math::PxPyPzEVector getMomentum ( const ROOT::Math::PxPyPzEVector &  vector ) const

overridevirtual

Get Lorentz vector in cms frame.

Parameters

vector

Lorentz vector from particle

Returns

Lorentz vector in cms frame

Implements ReferenceFrame.

Definition at line 122 of file ReferenceFrame.cc.

{
  // 1. Boost momentum into cms frame
  return m_transform.rotateLabToCms() * vector;
}

getMomentumErrorMatrix() [1/2]

virtual TMatrixFSym getMomentumErrorMatrix ( const Particle *  particle ) const

inlinevirtualinherited

Wrapper for particles.

Parameters

particle

particle

Returns

Covariance matrix in reference frame

Definition at line 77 of file ReferenceFrame.h.

    {
      return getMomentumErrorMatrix(particle->getMomentumErrorMatrix());
    }

getMomentumErrorMatrix() [2/2]

TMatrixFSym getMomentumErrorMatrix ( const TMatrixFSym &  matrix ) const

overridevirtual

Get Momentum error matrix in cms frame.

Parameters

matrix

Covariance matrix from particle

Returns

Covariance matrix in cms frame

Implements ReferenceFrame.

Definition at line 128 of file ReferenceFrame.cc.

{
  TMatrixD lorentzrot(4, 4);
 
  m_transform.rotateLabToCms().GetRotationMatrix(lorentzrot);
 
  TMatrixFSym tmp_matrix(matrix);
  return tmp_matrix.Similarity(lorentzrot);
}

getVertex() [1/2]

virtual ROOT::Math::XYZVector getVertex ( const Particle *  particle ) const

inlinevirtualinherited

Wrapper for particles.

Parameters

particle

Returns

3-vector in reference frame

Definition at line 43 of file ReferenceFrame.h.

    {
      return getVertex(particle->getVertex());
    }

getVertex() [2/2]

ROOT::Math::XYZVector getVertex ( const ROOT::Math::XYZVector &  vector ) const

overridevirtual

Get vertex 3-vector in cms frame.

Parameters

vector

3-vector from particle

Returns

3-vector in cms frame

Implements ReferenceFrame.

Definition at line 110 of file ReferenceFrame.cc.

{
  // Transform Vertex from lab into cms frame:
  // TODO 0: Subtract fitted IP similar to RestFrame
  // 1. Use Lorentz Transformation to Boost Vertex vector into cms frame
  // 2. Subtract movement of vertex end due to the time difference between
  //    the former simultaneous measured vertex points (see derivation of Lorentz contraction)
  ROOT::Math::PxPyPzEVector a = m_transform.rotateLabToCms() * ROOT::Math::PxPyPzEVector(vector.X(), vector.Y(), vector.Z(), 0);
  return a.Vect() - ROOT::Math::XYZVector(m_transform.getBoostVector().X(), m_transform.getBoostVector().Y(),
                                          m_transform.getBoostVector().Z()) * a.T();
}

getVertexErrorMatrix() [1/2]

virtual TMatrixFSym getVertexErrorMatrix ( const Particle *  particle ) const

inlinevirtualinherited

Wrapper for particles.

Parameters

particle

Returns

Covariance matrix in reference frame

Definition at line 94 of file ReferenceFrame.h.

    {
      return getVertexErrorMatrix(particle->getVertexErrorMatrix());
    }

getVertexErrorMatrix() [2/2]

TMatrixFSym getVertexErrorMatrix ( const TMatrixFSym &  matrix ) const

overridevirtual

Get Vertex error matrix in cms frame.

Parameters

matrix

Covariance matrix from particle

Returns

Covariance matrix in cms frame

Implements ReferenceFrame.

Definition at line 138 of file ReferenceFrame.cc.

{
  TMatrixD lorentzrot(4, 3);
 
  TMatrixD labToCmsFrame(4, 4);
  m_transform.rotateLabToCms().GetRotationMatrix(labToCmsFrame);
  for (int i = 0; i < 4; ++i)
    for (int j = 0; j < 3; ++j)
      lorentzrot(i, j) = labToCmsFrame(i, j);
 
  TMatrixFSym tmp_matrix(matrix);
  auto rotated_error_matrix = tmp_matrix.Similarity(lorentzrot);
 
  TMatrixD timeshift(3, 4);
  timeshift.Zero();
  auto boost_vector = m_transform.getBoostVector();
  timeshift(0, 0) = 1;
  timeshift(1, 1) = 1;
  timeshift(2, 2) = 1;
  timeshift(0, 3) = boost_vector(0);
  timeshift(1, 3) = boost_vector(1);
  timeshift(2, 3) = boost_vector(2);
 
  return rotated_error_matrix.Similarity(timeshift);
}

Pop()

static void Pop ( )

inlinestaticprivateinherited

Pop current rest frame.

Definition at line 118 of file ReferenceFrame.h.

    {
      m_reference_frames.pop();
    }

Push()

static void Push ( const ReferenceFrame *  frame )

inlinestaticprivateinherited

Push rest frame of given particle.

Parameters

frame

Use this reference frame

Definition at line 110 of file ReferenceFrame.h.

    {
      m_reference_frames.push(frame);
    }

Member Data Documentation

m_reference_frames

std::stack< const ReferenceFrame * > m_reference_frames

staticprivateinherited

Stack of current rest frames.

Definition at line 123 of file ReferenceFrame.h.

m_transform

PCmsLabTransform m_transform

private

Lab to CMS Transform.

Definition at line 247 of file ReferenceFrame.h.

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The documentation for this class was generated from the following files:

• analysis/utility/include/ReferenceFrame.h
• analysis/utility/src/ReferenceFrame.cc