ECALPositionCalculator Class Reference

#include <ECALPositionCalculator.h>

Public Member Functions
double	ecalEta (const math::XYZVector &momentum, const math::XYZPoint &vertex)
double	ecalPhi (const MagneticField *magField, const math::XYZVector &momentum, const math::XYZPoint &vertex, const int charge)
	ECALPositionCalculator ()

Detailed Description

Definition at line 9 of file ECALPositionCalculator.h.

Constructor & Destructor Documentation

ECALPositionCalculator::ECALPositionCalculator ( )

inline

Definition at line 12 of file ECALPositionCalculator.h.

References ALCARECOTkAlJpsiMuMu_cff::charge, ecalEta(), and ecalPhi().

{ };

Member Function Documentation

double ECALPositionCalculator::ecalEta	(	const math::XYZVector &	momentum,
		const math::XYZPoint &	vertex
	)

Definition at line 69 of file ECALPositionCalculator.cc.

References ETA, etaBarrelEndcap, cmsBatch::log, Geom::pi(), R_ECAL, funct::tan(), theta(), and Z_Endcap.

Referenced by ECALPositionCalculator().

{

   // Get kinematic variables

   float etaParticle = momentum.eta();
   float vZ = vertex.z();
   float vRho = vertex.Rho();

   if (etaParticle != 0.0)
   {
      float theta = 0.0;
      float zEcal = (R_ECAL-vRho)*sinh(etaParticle)+vZ;
      
      if(zEcal != 0.0) theta = atan(R_ECAL/zEcal);
      if(theta < 0.0) theta = theta + Geom::pi() ;

      float ETA = - log(tan(0.5*theta));
      
      if( fabs(ETA) > etaBarrelEndcap )
      {
         float Zend = Z_Endcap ;
     if(etaParticle < 0.0 )  Zend = - Zend;
     float Zlen = Zend - vZ ;
     float RR = Zlen/sinh(etaParticle);
     theta = atan((RR+vRho)/Zend);
     if(theta < 0.0) theta = theta+Geom::pi();
     ETA = -log(tan(0.5*theta));
      }
      return ETA;

    } else {
       edm::LogWarning("")  << "[EcalPositionFromTrack::etaTransformation] Warning: "
                << "Eta equals to zero, not correcting";
       return etaParticle;
    }

}

double ECALPositionCalculator::ecalPhi	(	const MagneticField *	magField,
		const math::XYZVector &	momentum,
		const math::XYZPoint &	vertex,
		const int	charge
	)

Definition at line 14 of file ECALPositionCalculator.cc.

References ALCARECOTkAlJpsiMuMu_cff::charge, etaBarrelEndcap, MagneticField::inTesla(), phi, Geom::pi(), Geom::twoPi(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by EgammaHLTElectronDetaDphiProducer::calDEtaDPhiSCTrk(), and ECALPositionCalculator().

{

   // Get kinematic variables

   float ptParticle = momentum.Rho();
   float etaParticle = momentum.eta();
   float phiParticle = momentum.phi();
   float vRho = vertex.Rho();

   // Magnetic field

   const float RBARM = 1.357 ;      // was 1.31 , updated on 16122003
   const float ZENDM = 3.186 ;      // was 3.15 , updated on 16122003

   float rbend = RBARM-(vRho/100.0);    //Assumed vRho in cm
   float bend  = 0.3 * magField->inTesla(GlobalPoint(0.,0.,0.)).z() * rbend / 2.0; 
   float phi = 0.0;

   if( fabs(etaParticle) <=  etaBarrelEndcap)
   {
      if (fabs(bend/ptParticle) <= 1.) 
      {
         phi = phiParticle - asin(bend/ptParticle)*charge;
     if(phi >  Geom::pi()) phi = phi - Geom::twoPi();
     if(phi < -Geom::pi()) phi = phi + Geom::twoPi();
      } else {
         edm::LogWarning("") << "[EcalPositionFromTrack::phiTransformation] Warning: "
                     << "Too low Pt, giving up";
     return phiParticle;
      }

   } // end if in the barrel
  
   if(fabs(etaParticle) > etaBarrelEndcap)
   {
      float rHit = 0.0;
      rHit = ZENDM / sinh(fabs(etaParticle));
      if (fabs(((rHit-(vRho/100.0))/rbend)*bend/ptParticle) <= 1.0)
      {
         phi = phiParticle - asin(((rHit-(vRho/100.0)) / rbend)*bend/ptParticle)*charge;
     if(phi >  Geom::pi()) phi = phi - Geom::twoPi();
     if(phi < -Geom::pi()) phi = phi + Geom::twoPi();
      } else {
         edm::LogWarning("") << "[EcalPositionFromTrack::phiTransformation] Warning: "
                     << "Too low Pt, giving up";
     return phiParticle;
      }  

    } // end if in the endcap
  
   return phi;

}