JetEnergyShift Class Reference

Plugin to shift the jet energy scale and recalculate the MET accordingly. More...

Inheritance diagram for JetEnergyShift:

Public Member Functions
	JetEnergyShift (const edm::ParameterSet &)
	default constructor More...
	~JetEnergyShift ()
	default destructor More...
Public Member Functions inherited from edm::EDProducer
	EDProducer ()
virtual	~EDProducer ()
Public Member Functions inherited from edm::ProducerBase
	ProducerBase ()
void	registerProducts (ProducerBase *, ProductRegistry *, ModuleDescription const &)
boost::function< void(const BranchDescription &)>	registrationCallback () const
	used by the fwk to register list of products More...
virtual	~ProducerBase ()

Private Member Functions
virtual void	produce (edm::Event &, const edm::EventSetup &)
	rescale jet energy and recalculated MET More...

Private Attributes
edm::InputTag	inputJets_
	jet input collection More...
edm::InputTag	inputMETs_
	met input collection More...
double	jetEMLimitForMET_
	limit on the emf of the jet for Type1 MET corrections More...
double	jetPTThresholdForMET_
	threshold on (raw!) jet pt for Type1 MET corrections More...
std::string	outputJets_
	jet output collection More...
std::string	outputMETs_
	MET output collection. More...
double	scaleFactor_
	scale factor for the rescaling More...

Additional Inherited Members
Public Types inherited from edm::EDProducer
typedef EDProducer	ModuleType
typedef WorkerT< EDProducer >	WorkerType
Public Types inherited from edm::ProducerBase
typedef ProductRegistryHelper::TypeLabelList	TypeLabelList
Static Public Member Functions inherited from edm::EDProducer
static const std::string &	baseType ()
static void	fillDescriptions (ConfigurationDescriptions &descriptions)
Protected Member Functions inherited from edm::EDProducer
CurrentProcessingContext const *	currentContext () const
Protected Member Functions inherited from edm::ProducerBase
template<class TProducer , class TMethod >
void	callWhenNewProductsRegistered (TProducer *iProd, TMethod iMethod)

Detailed Description

Plugin to shift the jet energy scale and recalculate the MET accordingly.

Plugin to shift the jet energy scale and recalculate the MET accordingly. The module mimics the assumption that the jet energy scale (JES) has been estimated wrong by a factor of scaleFactor, corresponding to a L2L3 corrected jet. The p4 of the patJet is beeing rescaled. All other patJet properties stay the same. The MET is recalculated taking the shifted JES into account for the Type1 MET correction. For the patMET the rescaled sumET and the p4 are stored. The different correction levels are lost for the new collection. The module has the following parameters:

inputJets : input collection for MET (expecting patMET). inputMETs : input collection for jets (expecting patJets). scaleFactor : scale factor to which to shift the JES. jetPTThresholdForMET : pt threshold for (uncorrected!) jets considered for Type1 MET corrections. jetEMLimitForMET : limit in em fraction for Type1 MET correction.

For expected parameters for jetPTThresholdForMET and jetEMLimitForMET have a look at: JetMETCorrections/Type1MET/python/MetType1Corrections_cff.py. Two output collections are written to file with instance label corresponding to the input label of the jet and met input collections.

Definition at line 31 of file JetEnergyShift.cc.

Constructor & Destructor Documentation

JetEnergyShift::JetEnergyShift ( const edm::ParameterSet &  cfg )

explicit

default constructor

Definition at line 64 of file JetEnergyShift.cc.

References inputJets_, inputMETs_, edm::InputTag::label(), outputJets_, and outputMETs_.

                                                        :
  inputJets_           (cfg.getParameter<edm::InputTag>("inputJets"           )),
  inputMETs_           (cfg.getParameter<edm::InputTag>("inputMETs"           )),
  scaleFactor_         (cfg.getParameter<double>       ("scaleFactor"         )),
  jetPTThresholdForMET_(cfg.getParameter<double>       ("jetPTThresholdForMET")),
  jetEMLimitForMET_    (cfg.getParameter<double>       ("jetEMLimitForMET"    ))
{
  // use label of input to create label for output
  outputJets_ = inputJets_.label();
  outputMETs_ = inputMETs_.label();
  // register products
  produces<std::vector<pat::Jet> >(outputJets_);
  produces<std::vector<pat::MET> >(outputMETs_);
}

JetEnergyShift::~JetEnergyShift ( )

inline

default destructor

Definition at line 37 of file JetEnergyShift.cc.

{};

Member Function Documentation

void JetEnergyShift::produce ( edm::Event &  event, const edm::EventSetup &  setup  )

privatevirtual

rescale jet energy and recalculated MET

Implements edm::EDProducer.

Definition at line 80 of file JetEnergyShift.cc.

References reco::LeafCandidate::et(), inputJets_, inputMETs_, metsig::jet, jetEMLimitForMET_, jetPTThresholdForMET_, analyzePatCleaning_cfg::jets, CaloMET_cfi::met, outputJets_, outputMETs_, reco::LeafCandidate::px(), reco::LeafCandidate::py(), reco::Jet::scaleEnergy(), scaleFactor_, mathSSE::sqrt(), and reco::MET::sumEt().

{
  edm::Handle<std::vector<pat::Jet> > jets;
  event.getByLabel(inputJets_, jets);

  edm::Handle<std::vector<pat::MET> > mets;
  event.getByLabel(inputMETs_, mets);
  
  std::auto_ptr<std::vector<pat::Jet> > pJets(new std::vector<pat::Jet>);
  std::auto_ptr<std::vector<pat::MET> > pMETs(new std::vector<pat::MET>);

  double dPx    = 0.;
  double dPy    = 0.;
  double dSumEt = 0.;

  for(std::vector<pat::Jet>::const_iterator jet = jets->begin(); jet != jets->end(); ++jet) {
    pat::Jet scaledJet = *jet;
    scaledJet.scaleEnergy( scaleFactor_ );
    pJets->push_back( scaledJet );
    // consider jet scale shift only if the raw jet pt and emf 
    // is above the thresholds given in the module definition
    if(jet->correctedJet("raw").pt() > jetPTThresholdForMET_
       && jet->emEnergyFraction() < jetEMLimitForMET_) {
      dPx    += scaledJet.px() - jet->px();
      dPy    += scaledJet.py() - jet->py();
      dSumEt += scaledJet.et() - jet->et();
    }
  }

  // scale MET accordingly
  pat::MET met = *(mets->begin());
  double scaledMETPx = met.px() - dPx;
  double scaledMETPy = met.py() - dPy;
  pat::MET scaledMET(reco::MET(met.sumEt()+dSumEt, reco::MET::LorentzVector(scaledMETPx, scaledMETPy, 0, sqrt(scaledMETPx*scaledMETPx+scaledMETPy*scaledMETPy)), reco::MET::Point(0,0,0)));
  pMETs->push_back( scaledMET );
  event.put(pJets, outputJets_);
  event.put(pMETs, outputMETs_);
}

Member Data Documentation

edm::InputTag JetEnergyShift::inputJets_

private

jet input collection

Definition at line 45 of file JetEnergyShift.cc.

Referenced by JetEnergyShift(), and produce().

edm::InputTag JetEnergyShift::inputMETs_

private

met input collection

Definition at line 47 of file JetEnergyShift.cc.

Referenced by JetEnergyShift(), and produce().

double JetEnergyShift::jetEMLimitForMET_

private

limit on the emf of the jet for Type1 MET corrections

Definition at line 57 of file JetEnergyShift.cc.

Referenced by produce().

double JetEnergyShift::jetPTThresholdForMET_

private

threshold on (raw!) jet pt for Type1 MET corrections

Definition at line 55 of file JetEnergyShift.cc.

Referenced by produce().

std::string JetEnergyShift::outputJets_

private

jet output collection

Definition at line 49 of file JetEnergyShift.cc.

Referenced by JetEnergyShift(), and produce().

std::string JetEnergyShift::outputMETs_

private

MET output collection.

Definition at line 51 of file JetEnergyShift.cc.

Referenced by JetEnergyShift(), and produce().

double JetEnergyShift::scaleFactor_

private

scale factor for the rescaling

Definition at line 53 of file JetEnergyShift.cc.

Referenced by produce().