#include <PhotonEnergyCalibrator.h>

Public Types
enum	EventType { EventType::DATA, EventType::MC }

Public Member Functions
std::array< float, EGEnergySysIndex::kNrSysErrs >	calibrate (reco::Photon &photon, const unsigned int runNumber, const EcalRecHitCollection *recHits, edm::StreamID const &id, const EventType eventType) const

std::array< float, EGEnergySysIndex::kNrSysErrs >	calibrate (reco::Photon &photon, const unsigned int runNumber, const EcalRecHitCollection *recHits, const float smearNrSigma, const EventType eventType) const

void	initPrivateRng (TRandom *rnd)

	PhotonEnergyCalibrator ()

	PhotonEnergyCalibrator (const std::string &correctionFile)

void	setMinEt (float val)

	~PhotonEnergyCalibrator ()

Private Member Functions
double	gauss (edm::StreamID const &id) const

void	setEnergyAndSystVarations (const float scale, const float smearNrSigma, const float et, const EnergyScaleCorrection::ScaleCorrection &scaleCorr, const EnergyScaleCorrection::SmearCorrection &smearCorr, reco::Photon &photon, std::array< float, EGEnergySysIndex::kNrSysErrs > &energyData) const

Private Attributes
EnergyScaleCorrection	correctionRetriever_

float	minEt_

TRandom *	rng_

Static Private Attributes
static const EnergyScaleCorrection::ScaleCorrection	defaultScaleCorr_

static const EnergyScaleCorrection::SmearCorrection	defaultSmearCorr_

Detailed Description

Definition at line 20 of file PhotonEnergyCalibrator.h.

Member Enumeration Documentation

enum PhotonEnergyCalibrator::EventType

strong

Enumerator
DATA
MC

Definition at line 23 of file PhotonEnergyCalibrator.h.

                       {
     DATA,
     MC,
   };

Constructor & Destructor Documentation

PhotonEnergyCalibrator::PhotonEnergyCalibrator ( )

inline

Definition at line 28 of file PhotonEnergyCalibrator.h.

References electrons_cff::correctionFile, and AlCaHLTBitMon_QueryRunRegistry::string.

28 {}

PhotonEnergyCalibrator::PhotonEnergyCalibrator ( const std::string & correctionFile )

Definition at line 11 of file PhotonEnergyCalibrator.cc.

                                                                              :
   correctionRetriever_(correctionFile),
   rng_(nullptr),
   minEt_(1.0)
 {
 
 }

PhotonEnergyCalibrator::~PhotonEnergyCalibrator ( )

inline

Definition at line 30 of file PhotonEnergyCalibrator.h.

References initPrivateRng().

30 {}

Member Function Documentation

std::array< float, EGEnergySysIndex::kNrSysErrs > PhotonEnergyCalibrator::calibrate	(	reco::Photon &	photon,
		const unsigned int	runNumber,
		const EcalRecHitCollection *	recHits,
		edm::StreamID const &	id,
		const EventType	eventType
	)		const

Correct this photon. StreamID is needed when used with CMSSW Random Number Generator

Definition at line 25 of file PhotonEnergyCalibrator.cc.

References gauss().

Referenced by initPrivateRng(), CalibratedPhotonProducerT< T >::produce(), and setMinEt().

 {
   return calibrate(photon,runNumber,recHits,gauss(id),eventType);
 }

std::array< float, EGEnergySysIndex::kNrSysErrs > PhotonEnergyCalibrator::calibrate	(	reco::Photon &	photon,
		const unsigned int	runNumber,
		const EcalRecHitCollection *	recHits,
		const float	smearNrSigma,
		const EventType	eventType
	)		const

Definition at line 34 of file PhotonEnergyCalibrator.cc.

 {
   const float scEtaAbs = std::abs(photon.superCluster()->eta());
   const float et = photon.getCorrectedEnergy(reco::Photon::P4type::regression2) / cosh(scEtaAbs);
 
   if (et < minEt_) {
     std::array<float,EGEnergySysIndex::kNrSysErrs> retVal;
     retVal.fill(photon.getCorrectedEnergy(reco::Photon::P4type::regression2));
     retVal[EGEnergySysIndex::kScaleValue]  = 1.0;
     retVal[EGEnergySysIndex::kSmearValue]  = 0.0;
     retVal[EGEnergySysIndex::kSmearNrSigma]  = smearNrSigma;
     retVal[EGEnergySysIndex::kEcalErrPreCorr] = photon.getCorrectedEnergyError(reco::Photon::P4type::regression2); 
     retVal[EGEnergySysIndex::kEcalErrPostCorr] = photon.getCorrectedEnergyError(reco::Photon::P4type::regression2);
     retVal[EGEnergySysIndex::kEcalTrkPreCorr] = 0.;
     retVal[EGEnergySysIndex::kEcalTrkErrPreCorr] = 0.;
     retVal[EGEnergySysIndex::kEcalTrkPostCorr] = 0.;
     retVal[EGEnergySysIndex::kEcalTrkErrPostCorr] = 0.;
     
     return retVal;
   }
 
   const DetId seedDetId = photon.superCluster()->seed()->seed();
   EcalRecHitCollection::const_iterator seedRecHit = recHits->find(seedDetId);
   unsigned int gainSeedSC = 12;
   if (seedRecHit != recHits->end()) {
     if(seedRecHit->checkFlag(EcalRecHit::kHasSwitchToGain6)) gainSeedSC = 6;
     if(seedRecHit->checkFlag(EcalRecHit::kHasSwitchToGain1)) gainSeedSC = 1;
   }
   
   const EnergyScaleCorrection::ScaleCorrection* scaleCorr = correctionRetriever_.getScaleCorr(runNumber, et, scEtaAbs, photon.full5x5_r9(), gainSeedSC);  
   const EnergyScaleCorrection::SmearCorrection* smearCorr = correctionRetriever_.getSmearCorr(runNumber, et, scEtaAbs, photon.full5x5_r9(), gainSeedSC);  
   if(scaleCorr==nullptr) scaleCorr=&defaultScaleCorr_;
   if(smearCorr==nullptr) smearCorr=&defaultSmearCorr_;
  
 
   std::array<float,EGEnergySysIndex::kNrSysErrs> uncertainties{};
   
   uncertainties[EGEnergySysIndex::kScaleValue]  = scaleCorr->scale();
   uncertainties[EGEnergySysIndex::kSmearValue]  = smearCorr->sigma(et); //even though we use scale = 1.0, we still store the value returned for MC
   uncertainties[EGEnergySysIndex::kSmearNrSigma]  = smearNrSigma;
   //MC central values are not scaled (scale = 1.0), data is not smeared (smearNrSigma = 0)
   //smearing still has a second order effect on data as it enters the E/p combination as an 
   //extra uncertainty on the calo energy
   //MC gets all the scale systematics
   if(eventType == EventType::DATA){ 
     setEnergyAndSystVarations(scaleCorr->scale(),0.,et,*scaleCorr,*smearCorr,photon,uncertainties);
   }else if(eventType == EventType::MC){
     setEnergyAndSystVarations(1.0,smearNrSigma,et,*scaleCorr,*smearCorr,photon,uncertainties);
   }
   
   return uncertainties;
   
 }

double PhotonEnergyCalibrator::gauss ( edm::StreamID const & id ) const

private

Return a number distributed as a unit gaussian, drawn from the private RNG if initPrivateRng was called, or from the CMSSW RandomNumberGenerator service If synchronization is set to true, it returns a fixed number (1.0)

Definition at line 147 of file PhotonEnergyCalibrator.cc.

References Exception, edm::RandomNumberGenerator::getEngine(), edm::Service< T >::isAvailable(), and rng_.

Referenced by calibrate(), and setMinEt().

 {
   if (rng_) {
     return rng_->Gaus();
   } else {
     edm::Service<edm::RandomNumberGenerator> rng;
     if ( !rng.isAvailable() ) {
       throw cms::Exception("Configuration")
     << "XXXXXXX requires the RandomNumberGeneratorService\n"
     "which is not present in the configuration file.  You must add the service\n"
     "in the configuration file or remove the modules that require it.";
         }
     CLHEP::RandGaussQ gaussDistribution(rng->getEngine(id), 0.0, 1.0);
     return gaussDistribution.fire();
   }
 }

void PhotonEnergyCalibrator::initPrivateRng ( TRandom * rnd )

Initialize with a random number generator (if not done, it will use the CMSSW service) Caller code owns the TRandom.

Definition at line 19 of file PhotonEnergyCalibrator.cc.

References calibrate(), and rng_.

Referenced by CalibratedPhotonProducerT< T >::CalibratedPhotonProducerT(), and ~PhotonEnergyCalibrator().

 {
   rng_ = rnd;
 }

void PhotonEnergyCalibrator::setEnergyAndSystVarations	(	const float	scale,
		const float	smearNrSigma,
		const float	et,
		const EnergyScaleCorrection::ScaleCorrection &	scaleCorr,
		const EnergyScaleCorrection::SmearCorrection &	smearCorr,
		reco::Photon &	photon,
		std::array< float, EGEnergySysIndex::kNrSysErrs > &	energyData
	)		const

private

Definition at line 92 of file PhotonEnergyCalibrator.cc.

Referenced by calibrate(), and setMinEt().

 {
  
   const float smear = smearCorr.sigma(et);   
   const float smearRhoUp = smearCorr.sigma(et,1,0);
   const float smearRhoDn = smearCorr.sigma(et,-1,0);
   const float smearPhiUp = smearCorr.sigma(et,0,1);
   const float smearPhiDn = smearCorr.sigma(et,0,-1);
  
   const float corr = scale + smear * smearNrSigma;
   const float corrRhoUp = scale + smearRhoUp * smearNrSigma;
   const float corrRhoDn = scale + smearRhoDn * smearNrSigma;
   const float corrPhiUp = scale + smearPhiUp * smearNrSigma;
   const float corrPhiDn = scale + smearPhiDn * smearNrSigma;
   const float corrUp = corrRhoUp;
   const float corrDn = corrRhoDn;
 
   
   const double oldEcalEnergy = photon.getCorrectedEnergy(reco::Photon::P4type::regression2);
   const double oldEcalEnergyError = photon.getCorrectedEnergyError(reco::Photon::P4type::regression2);
   
   energyData[EGEnergySysIndex::kEcalPreCorr] = oldEcalEnergy;
   energyData[EGEnergySysIndex::kEcalErrPreCorr] = oldEcalEnergyError;
 
   const double newEcalEnergy      = oldEcalEnergy * corr;
   const double newEcalEnergyError = std::hypot(oldEcalEnergyError * corr, smear * newEcalEnergy);
   photon.setCorrectedEnergy(reco::Photon::P4type::regression2, newEcalEnergy, newEcalEnergyError, true);
   
   energyData[EGEnergySysIndex::kScaleStatUp]   = oldEcalEnergy * (corr + scaleCorr.scaleErrStat());
   energyData[EGEnergySysIndex::kScaleStatDown] = oldEcalEnergy * (corr - scaleCorr.scaleErrStat());
   energyData[EGEnergySysIndex::kScaleSystUp]   = oldEcalEnergy * (corr + scaleCorr.scaleErrSyst());
   energyData[EGEnergySysIndex::kScaleSystDown] = oldEcalEnergy * (corr - scaleCorr.scaleErrSyst());
   energyData[EGEnergySysIndex::kScaleGainUp]   = oldEcalEnergy * (corr + scaleCorr.scaleErrGain());
   energyData[EGEnergySysIndex::kScaleGainDown] = oldEcalEnergy * (corr - scaleCorr.scaleErrGain());
   energyData[EGEnergySysIndex::kSmearRhoUp]    = oldEcalEnergy * corrRhoUp;
   energyData[EGEnergySysIndex::kSmearRhoDown]  = oldEcalEnergy * corrRhoDn;
   energyData[EGEnergySysIndex::kSmearPhiUp]    = oldEcalEnergy * corrPhiUp;
   energyData[EGEnergySysIndex::kSmearPhiDown]  = oldEcalEnergy * corrPhiDn;
   
   // The total variation
   energyData[EGEnergySysIndex::kScaleUp]   = oldEcalEnergy * (corr + scaleCorr.scaleErr(EnergyScaleCorrection::kErrStatSystGain));
   energyData[EGEnergySysIndex::kScaleDown] = oldEcalEnergy * (corr - scaleCorr.scaleErr(EnergyScaleCorrection::kErrStatSystGain));
   energyData[EGEnergySysIndex::kSmearUp]   = oldEcalEnergy * corrUp;
   energyData[EGEnergySysIndex::kSmearDown] = oldEcalEnergy * corrDn;
 
   
   energyData[EGEnergySysIndex::kEcalPostCorr] = photon.getCorrectedEnergy(reco::Photon::P4type::regression2);
   energyData[EGEnergySysIndex::kEcalErrPostCorr] = photon.getCorrectedEnergyError(reco::Photon::P4type::regression2);
 }  