EcalClusterCrackCorrection Class Reference

#include <EcalClusterCrackCorrection.h>

Inheritance diagram for EcalClusterCrackCorrection:

Public Member Functions
	EcalClusterCrackCorrection (const edm::ParameterSet &)
virtual float	getValue (const reco::BasicCluster &, const EcalRecHitCollection &) const
virtual float	getValue (const reco::SuperCluster &, const int mode) const
virtual float	getValue (const reco::CaloCluster &) const
Public Member Functions inherited from EcalClusterCrackCorrectionBaseClass
void	checkInit () const
	EcalClusterCrackCorrectionBaseClass ()
	EcalClusterCrackCorrectionBaseClass (const edm::ParameterSet &)
const EcalClusterCrackCorrParameters *	getParameters () const
virtual void	init (const edm::EventSetup &es)
virtual	~EcalClusterCrackCorrectionBaseClass ()
Public Member Functions inherited from EcalClusterFunctionBaseClass
virtual	~EcalClusterFunctionBaseClass ()

Additional Inherited Members
Protected Attributes inherited from EcalClusterCrackCorrectionBaseClass
const edm::EventSetup *	es_
edm::ESHandle < EcalClusterCrackCorrParameters >	esParams_
const EcalClusterCrackCorrParameters *	params_

Detailed Description

Function to correct cluster for cracks in the calorimeter

$Id: EcalClusterCrackCorrection.h $Date: $Revision:

Author

Federico Ferri, CEA Saclay, November 2008

Definition at line 15 of file EcalClusterCrackCorrection.h.

Constructor & Destructor Documentation

EcalClusterCrackCorrection::EcalClusterCrackCorrection ( const edm::ParameterSet &  )

inline

Definition at line 17 of file EcalClusterCrackCorrection.h.

{};

Member Function Documentation

float EcalClusterCrackCorrection::getValue ( const reco::BasicCluster &  basicCluster, const EcalRecHitCollection &  recHit  ) const

virtual

Implements EcalClusterCrackCorrectionBaseClass.

Definition at line 26 of file EcalClusterCrackCorrection.cc.

References EcalClusterCrackCorrectionBaseClass::checkInit(), gather_cfg::cout, EcalFunParams::params(), and EcalClusterCrackCorrectionBaseClass::params_.

Referenced by getValue().

{
  //this is a dummy function, could be deleted in mother classes and here
        checkInit();

        // private member params_ = EcalClusterCrackCorrectionParameters
        // (see in CondFormats/EcalObjects/interface)
        EcalFunctionParameters::const_iterator it;
        std::cout << "[[EcalClusterCrackCorrectionBaseClass::getValue]] " 
                << params_->params().size() << " parameters:";
        for ( it = params_->params().begin(); it != params_->params().end(); ++it ) {
                std::cout << " " << *it;
        }
        std::cout << "\n";
        return 1;
}

float EcalClusterCrackCorrection::getValue ( const reco::SuperCluster &  superCluster, const int  mode  ) const

virtual

Implements EcalClusterCrackCorrectionBaseClass.

Definition at line 174 of file EcalClusterCrackCorrection.cc.

References EcalClusterCrackCorrectionBaseClass::checkInit(), getValue(), and reco::SuperCluster::seed().

{
  checkInit();

  //********************************************************************************************************************//
  //These ECAL barrel module and supermodule border corrections correct a photon energy for leakage outside a 5x5 crystal cluster. They  depend on the local position in the hit crystal. The hit crystal needs to be at the border of a barrel module. The local position coordinates, called later EtaCry and PhiCry in the code, are comprised between -0.5 and 0.5 and correspond to the distance between the photon supercluster position and the center of the hit crystal, expressed in number of  crystal widthes. The correction parameters (that should be filled in CalibCalorimetry/EcalTrivialCondModules/python/EcalTrivialCondRetriever_cfi.py) were calculated using simulaion and thus take into account the effect of the magnetic field. They  only apply to unconverted photons in the barrel, but a use for non brem electrons could be considered (not tested yet). For more details, cf the CMS internal note 2009-013 by S. Tourneur and C. Seez

  //Beware: The user should make sure it only uses this correction factor for unconverted photons (or not breming electrons)

  return getValue(*(superCluster.seed()));

 
}

float EcalClusterCrackCorrection::getValue ( const reco::CaloCluster &  seedbclus ) const

virtual

Reimplemented from EcalClusterCrackCorrectionBaseClass.

Definition at line 44 of file EcalClusterCrackCorrection.cc.

References Abs(), EcalClusterCrackCorrectionBaseClass::checkInit(), HLT_25ns14e33_v1_cff::depth, DetId::Ecal, EcalBarrel, reco::CaloCluster::energy(), EcalClusterCrackCorrectionBaseClass::es_, reco::tau::disc::Eta(), PV3DBase< T, PVType, FrameType >::eta(), reco::CaloCluster::eta(), f, plotBeamSpotDB::first, g, relativeConstraints::geom, edm::EventSetup::get(), CaloSubdetectorGeometry::getGeometry(), reco::CaloCluster::hitsAndFractions(), EBDetId::ieta(), EBDetId::iphi(), relval_steps::k, cmsBatch::log, HLT_25ns14e33_v1_cff::offset, EcalFunParams::params(), EcalClusterCrackCorrectionBaseClass::params_, colinearityKinematic::Phi, PV3DBase< T, PVType, FrameType >::phi(), Phi_mpi_pi(), Pi, reco::CaloCluster::position(), funct::pow(), PV3DBase< T, PVType, FrameType >::theta(), and X0.

{
  checkInit();

  //correction factor to be returned, and to be calculated in this present function:
  double correction_factor=1.;
  double fetacor=1.; //eta dependent part of the correction factor
  double fphicor=1.; //phi dependent part of the correction factor


  //********************************************************************************************************************//
  //These ECAL barrel module and supermodule border corrections correct a photon energy for leakage outside a 5x5 crystal cluster. They  depend on the local position in the hit crystal. The hit crystal needs to be at the border of a barrel module. The local position coordinates, called later EtaCry and PhiCry in the code, are comprised between -0.5 and 0.5 and correspond to the distance between the photon supercluster position and the center of the hit crystal, expressed in number of  crystal widthes. The correction parameters (that should be filled in CalibCalorimetry/EcalTrivialCondModules/python/EcalTrivialCondRetriever_cfi.py) were calculated using simulaion and thus take into account the effect of the magnetic field. They  only apply to unconverted photons in the barrel, but a use for non brem electrons could be considered (not tested yet). For more details, cf the CMS internal note 2009-013 by S. Tourneur and C. Seez

  //Beware: The user should make sure it only uses this correction factor for unconverted photons (or not breming electrons)

  //const reco::CaloClusterPtr & seedbclus =  superCluster.seed();
  
  //If not barrel, return 1:
  if (TMath::Abs(seedbclus.eta()) >1.4442 ) return 1.;

  edm::ESHandle<CaloGeometry> pG;
  es_->get<CaloGeometryRecord>().get(pG); 
  
  const CaloSubdetectorGeometry* geom=pG->getSubdetectorGeometry(DetId::Ecal,EcalBarrel);//EcalBarrel = 1
  
  const math::XYZPoint position_ = seedbclus.position(); 
  double Theta = -position_.theta()+0.5*TMath::Pi();
  double Eta = position_.eta();
  double Phi = TVector2::Phi_mpi_pi(position_.phi());
  
  //Calculate expected depth of the maximum shower from energy (like in PositionCalc::Calculate_Location()):
  // The parameters X0 and T0 are hardcoded here because these values were used to calculate the corrections:
  const float X0 = 0.89; const float T0 = 7.4;
  double depth = X0 * (T0 + log(seedbclus.energy()));
  
  
  //search which crystal is closest to the cluster position and call it crystalseed:
  //std::vector<DetId> crystals_vector = seedbclus.getHitsByDetId();   //deprecated
  std::vector< std::pair<DetId, float> > crystals_vector = seedbclus.hitsAndFractions();
  float dphimin=999.;
  float detamin=999.;
  int ietaclosest = 0;
  int iphiclosest = 0;
  for (unsigned int icry=0; icry!=crystals_vector.size(); ++icry) {    
    EBDetId crystal(crystals_vector[icry].first);
    const CaloCellGeometry* cell=geom->getGeometry(crystal);
    GlobalPoint center_pos = (dynamic_cast<const TruncatedPyramid*>(cell))->getPosition(depth);
    double EtaCentr = center_pos.eta();
    double PhiCentr = TVector2::Phi_mpi_pi(center_pos.phi());
    if (TMath::Abs(EtaCentr-Eta) < detamin) {
      detamin = TMath::Abs(EtaCentr-Eta); 
      ietaclosest = crystal.ieta();
    }
    if (TMath::Abs(TVector2::Phi_mpi_pi(PhiCentr-Phi)) < dphimin) {
      dphimin = TMath::Abs(TVector2::Phi_mpi_pi(PhiCentr-Phi)); 
      iphiclosest = crystal.iphi();
    }
  }
  EBDetId crystalseed(ietaclosest, iphiclosest);
  
  // Get center cell position from shower depth
  const CaloCellGeometry* cell=geom->getGeometry(crystalseed);
  GlobalPoint center_pos = (dynamic_cast<const TruncatedPyramid*>(cell))->getPosition(depth);
  
  //if the seed crystal isn't neighbourgh of a supermodule border, don't apply the phi dependent crack corrections, but use the smaller phi dependent local containment correction instead.
  if (ietaclosest<0) iphiclosest = 361 - iphiclosest; //inversion of phi 3 degree tilt 
  int iphimod20 = iphiclosest%20;
   if ( iphimod20 >1 ) fphicor=1.;

   else{
      double PhiCentr = TVector2::Phi_mpi_pi(center_pos.phi());
      double PhiWidth = (TMath::Pi()/180.);
      double PhiCry = (TVector2::Phi_mpi_pi(Phi-PhiCentr))/PhiWidth;
      if (PhiCry>0.5) PhiCry=0.5;
      if (PhiCry<-0.5) PhiCry=-0.5;
       //flip to take into account ECAL barrel symmetries:
      if (ietaclosest<0) PhiCry *= -1.;

      //Fetching parameters of the polynomial (see  CMS IN-2009/013)
      double g[5];
      int offset = iphimod20==0 ? 
    10 //coefficients for one phi side of a SM
    : 15; //coefficients for the other side
      for (int k=0; k!=5; ++k) g[k] = (params_->params())[k+offset];
      
      fphicor=0.;
      for (int k=0; k!=5; ++k) fphicor += g[k]*std::pow(PhiCry,k);
   }
   
   //if the seed crystal isn't neighbourgh of a module border, don't apply the eta dependent crack corrections, but use the smaller eta dependent local containment correction instead.
  int ietamod20 = ietaclosest%20;
  if (TMath::Abs(ietaclosest) <25 || (TMath::Abs(ietamod20)!=5 && TMath::Abs(ietamod20)!=6) ) fetacor = 1.;
  
  else
    {      
      double ThetaCentr = -center_pos.theta()+0.5*TMath::Pi();
      double ThetaWidth = (TMath::Pi()/180.)*TMath::Cos(ThetaCentr);
      double EtaCry = (Theta-ThetaCentr)/ThetaWidth;    
      if (EtaCry>0.5) EtaCry=0.5;
      if (EtaCry<-0.5) EtaCry=-0.5;
      //flip to take into account ECAL barrel symmetries:
      if (ietaclosest<0) EtaCry *= -1.;
      
      //Fetching parameters of the polynomial (see  CMS IN-2009/013)
      double f[5];
      int offset = TMath::Abs(ietamod20)==5 ? 
    0 //coefficients for eta side of an intermodule gap closer to the interaction point
    : 5; //coefficients for the other eta side
      for (int k=0; k!=5; ++k) f[k] = (params_->params())[k+offset];
     
      fetacor=0.;
      for (int k=0; k!=5; ++k) fetacor += f[k]*std::pow(EtaCry,k); 
    }
  
  correction_factor = 1./(fetacor*fphicor);
  //*********************************************************************************************************************//
  
  //return the correction factor. Use it to multiply the cluster energy.
  return correction_factor;
}