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Public Member Functions | Private Attributes

CurvilinearTrajectoryParameters Class Reference

#include <CurvilinearTrajectoryParameters.h>

List of all members.

Public Member Functions

TrackCharge charge () const
 access to the charge
 CurvilinearTrajectoryParameters ()
 default constructor
 CurvilinearTrajectoryParameters (const GlobalPoint &aX, const GlobalVector &aP, TrackCharge aCharge)
 CurvilinearTrajectoryParameters (const AlgebraicVector5 &v, bool charged=true)
 CurvilinearTrajectoryParameters (double aQbp, double alambda, double aphi, double axT, double ayT, bool charged=true)
double lambda () const
double phi () const
double Qbp () const
double signedInverseMomentum () const
 access to the Signed Inverse momentum q/p (zero for neutrals)
bool updateP (double dP)
AlgebraicVector5 vector () const
double xT () const
double yT () const

Private Attributes

TrackCharge theCharge
double thelambda
double thephi
double theQbp
double thexT
double theyT

Detailed Description

Class providing access to a set of relevant parameters of a trajectory in a Curvilinear frame. The set consists of the following paramters: \ q/p: charged particles: charge(plus or minus one) divided by magnitude of momentum neutral particles: inverse magnitude of momentum lambda: the helix dip angle (pi/2 minus theta(polar angle)), defined in the global frame phi: the angle of inclination with the global x-axis in the transverse (global xy) plane xT: transverse position in the global xy plane and it points left when looking into the direction of the track yT: transverse position that forms a right-handed frame with xT and zT

Note that the frame is tangent to the track at the point of definition, with Z_T parallel to the track

Definition at line 29 of file CurvilinearTrajectoryParameters.h.


Constructor & Destructor Documentation

CurvilinearTrajectoryParameters::CurvilinearTrajectoryParameters ( ) [inline]

default constructor

Definition at line 34 of file CurvilinearTrajectoryParameters.h.

{}
CurvilinearTrajectoryParameters::CurvilinearTrajectoryParameters ( const AlgebraicVector5 v,
bool  charged = true 
)

Constructor from vector of parameters Expects a vector of parameters as defined above. For charged particles he charge will be determined by\ the sign of the first element. For neutral particles the last argument should be false, in which case the charge of the first element will be neglected.

Definition at line 4 of file CurvilinearTrajectoryParameters.cc.

References theCharge, thelambda, thephi, theQbp, thexT, and theyT.

                                                                                                        {
  theQbp    = v[0];
  thelambda = v[1];
  thephi    = v[2];
  thexT     = v[3];
  theyT     = v[4];
  
  if ( charged )
    theCharge = theQbp>0 ? 1 : -1;
  else
    theCharge = 0;
  
}
CurvilinearTrajectoryParameters::CurvilinearTrajectoryParameters ( double  aQbp,
double  alambda,
double  aphi,
double  axT,
double  ayT,
bool  charged = true 
)

Constructor from vector of parameters Expects a vector of parameters as defined above. For charged particles the charge will be determined by the sign of the first element. For neutral particles the last argument should be false, in which case the charge of the first element will be neglected.Constructor from individual curvilinear parameters Expects parameters as defined above.

Definition at line 19 of file CurvilinearTrajectoryParameters.cc.

References theCharge, and theQbp.

                                                                                                                                              : theQbp(aQbp), thelambda(alambda), thephi(aphi), thexT(axT), theyT(ayT) {
    
    if ( charged ) {
      theQbp = aQbp;
      theCharge = theQbp>0 ? 1 : -1;
    }
    else {
      theQbp = aQbp;
      theCharge = 0;
    }
}
CurvilinearTrajectoryParameters::CurvilinearTrajectoryParameters ( const GlobalPoint aX,
const GlobalVector aP,
TrackCharge  aCharge 
)

Constructor from a global vector, global point and track charge

Definition at line 32 of file CurvilinearTrajectoryParameters.cc.

References PV3DBase< T, PVType, FrameType >::mag(), mathSSE::sqrt(), theCharge, thelambda, thephi, theQbp, thexT, theyT, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

{
  if(aCharge==0) 
    theQbp = 1./aP.mag();
  else
    theQbp=aCharge/aP.mag();

  double pT2= aP.x()*aP.x()+aP.y()*aP.y();
  double pT =sqrt(pT2);
  thelambda= atan(aP.z()/pT);
  thephi=atan2(aP.y(),aP.x());
  thexT= (-aP.y()*aX.x()+ aP.x()*aX.y()) / pT;
  theyT= (-aX.x()*aP.x()*aP.z() - aX.y()*aP.z()*aP.y() + aX.z()*(pT2))  / (aP.mag()*pT);
  theCharge=aCharge;
}

Member Function Documentation

TrackCharge CurvilinearTrajectoryParameters::charge ( void  ) const [inline]

access to the charge

Definition at line 65 of file CurvilinearTrajectoryParameters.h.

References theCharge.

Referenced by signedInverseMomentum().

{return theCharge;}
double CurvilinearTrajectoryParameters::lambda ( ) const [inline]

Definition at line 81 of file CurvilinearTrajectoryParameters.h.

References thelambda.

Referenced by convert().

{   return thelambda;  }
double CurvilinearTrajectoryParameters::phi ( void  ) const [inline]

Definition at line 82 of file CurvilinearTrajectoryParameters.h.

References thephi.

Referenced by convert().

{    return thephi;  }
double CurvilinearTrajectoryParameters::Qbp ( ) const [inline]

Definition at line 80 of file CurvilinearTrajectoryParameters.h.

References theQbp.

{    return theQbp;  }
double CurvilinearTrajectoryParameters::signedInverseMomentum ( ) const [inline]

access to the Signed Inverse momentum q/p (zero for neutrals)

Definition at line 68 of file CurvilinearTrajectoryParameters.h.

References charge(), and theQbp.

Referenced by vector().

                                       {
    return charge()==0 ? 0. : theQbp;
  }
bool CurvilinearTrajectoryParameters::updateP ( double  dP)

Definition at line 61 of file CurvilinearTrajectoryParameters.cc.

References L1TEmulatorMonitor_cff::p, and theQbp.

                                                       {
  //FIXME. something is very likely to be missing here
  double p = 1./fabs(theQbp);
  if ((p += dP) <= 0.) return false;
  double newQbp = theQbp > 0. ? 1./p : -1./p;
  theQbp = newQbp;
  return true;
}
AlgebraicVector5 CurvilinearTrajectoryParameters::vector ( ) const

Vector of parameters with signed inverse momentum.

Vector of parameters as defined above, with the first element q/p.

Definition at line 51 of file CurvilinearTrajectoryParameters.cc.

References signedInverseMomentum(), thelambda, thephi, thexT, and theyT.

double CurvilinearTrajectoryParameters::xT ( ) const [inline]

Definition at line 83 of file CurvilinearTrajectoryParameters.h.

References thexT.

Referenced by convert().

{   return thexT;  }
double CurvilinearTrajectoryParameters::yT ( ) const [inline]

Definition at line 84 of file CurvilinearTrajectoryParameters.h.

References theyT.

Referenced by convert().

{    return theyT;  }

Member Data Documentation

Definition at line 95 of file CurvilinearTrajectoryParameters.h.

Referenced by charge(), and CurvilinearTrajectoryParameters().

Definition at line 91 of file CurvilinearTrajectoryParameters.h.

Referenced by CurvilinearTrajectoryParameters(), phi(), and vector().

Definition at line 92 of file CurvilinearTrajectoryParameters.h.

Referenced by CurvilinearTrajectoryParameters(), vector(), and xT().

Definition at line 93 of file CurvilinearTrajectoryParameters.h.

Referenced by CurvilinearTrajectoryParameters(), vector(), and yT().