#include <ParticleReplacerZtautau.h>

Inheritance diagram for ParticleReplacerZtautau:

Classes
struct	MinVisPtCut

struct	MinVisPtCutCombination

Public Member Functions
virtual void	beginJob ()

virtual void	beginRun (edm::Run &, const edm::EventSetup &)

virtual void	declareExtraProducts (MCParticleReplacer *)

virtual void	endJob ()

	ParticleReplacerZtautau (const edm::ParameterSet &)

virtual std::auto_ptr < HepMC::GenEvent >	produce (const std::vector< reco::Particle > &, const reco::Vertex =0, const HepMC::GenEvent =0, MCParticleReplacer *=0)

	~ParticleReplacerZtautau ()

Public Member Functions inherited from ParticleReplacerBase
virtual void	endRun ()

	ParticleReplacerBase (const edm::ParameterSet &)

virtual	~ParticleReplacerBase ()

Private Member Functions
void	cleanEvent (HepMC::GenEvent , HepMC::GenVertex )

HepMC::GenEvent *	processEventWithPythia (HepMC::GenEvent *)

HepMC::GenEvent *	processEventWithTauola (HepMC::GenEvent *)

bool	testEvent (HepMC::GenEvent *)

void	transformMuMu2LepLep (CLHEP::HepRandomEngine &randomEngine, reco::Particle , reco::Particle )

void	transformMuMu2TauNu (reco::Particle , reco::Particle )

Private Attributes
bool	applyMuonRadiationCorrection_

double	beamEnergy_

std::string	generatorMode_

int	maxNumberOfAttempts_

std::vector < MinVisPtCutCombination >	minVisPtCuts_

int	motherParticleID_

GenMuonRadiationAlgorithm *	muonRadiationAlgo_

bool	printEvent_

gen::Pythia6Service	pythia_

bool	rfMirror_

double	rfRotationAngle_

int	targetParticle1AbsPdgID_

double	targetParticle1Mass_

int	targetParticle2AbsPdgID_

double	targetParticle2Mass_

gen::TauolaInterfaceBase *	tauola_

unsigned int	transformationMode_

bool	useExternalGenerators_

bool	useTauola_

bool	useTauolaPolarization_

Static Private Attributes
static bool	tauola_isInitialized_ = false

Additional Inherited Members
Public Attributes inherited from ParticleReplacerBase
unsigned int	passed_

unsigned int	tried_

Protected Attributes inherited from ParticleReplacerBase
const double	tauMass_

int	verbosity_

Detailed Description

Auxiliary class to replace muons reconstructed in selected Z –> mu+ mu- events by generator level particles, which will be passed to detector simulation & reconstruction modules to create "hybrid" events ("embedded" leptons from Monte Carlo simulation, rest of the event taken from data)

Per default, the reconstructed muons are replaced by generator level tau leptons, which are passed to TAUOLA in order to produce generator level tau decay products.

For systematic/background studies, it is possible also to:

replace generator level muons
"embed" electrons or muons

Author: Manuel Zeise

Version

Revision:: 1.6

Id:: ParticleReplacerZtautau.h,v 1.6 2013/01/31 09:07:18 veelken Exp

Definition at line 40 of file ParticleReplacerZtautau.h.

Constructor & Destructor Documentation

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

explicit

Definition at line 43 of file ParticleReplacerZtautau.cc.

   : ParticleReplacerBase(cfg),
     generatorMode_(cfg.getParameter<std::string>("generatorMode")),
     beamEnergy_(cfg.getParameter<double>("beamEnergy")),
     applyMuonRadiationCorrection_(false),
     muonRadiationAlgo_(0),
     pythia_(cfg)
 {
   tauola_ = (gen::TauolaInterfaceBase*)(TauolaFactory::get()->create("Tauolapp113a",cfg.getParameter<edm::ParameterSet>("TauolaOptions")));
   // settings?
   // usesResource(edm::SharedResourceNames::kTauola);
   maxNumberOfAttempts_ = ( cfg.exists("maxNumberOfAttempts") ) ?
     cfg.getParameter<int>("maxNumberOfAttempts") : 10000;
 
   // transformationMode =
   //  0 - no transformation
   //  1 - mumu -> tautau
   //  2 - mumu -> ee
   //  3 - mumu -> taunu
   //  4 - munu -> taunu
   transformationMode_ = ( cfg.exists("transformationMode") ) ?
     cfg.getParameter<int>("transformationMode") : 1;
   if ( verbosity_ ) {
     edm::LogInfo("Replacer") << "generatorMode = " << generatorMode_ << "\n";
     edm::LogInfo("Replacer") << "transformationMode = " << transformationMode_ << "\n";
   }
 
   motherParticleID_ = ( cfg.exists("motherParticleID") ) ?
     cfg.getParameter<int>("motherParticleID") : 23;
 
   // require generator level visible tau decay products to exceed given transverse momentum.
   // The purpose of this flag is make maximal use of the available Zmumu events statistics
   // by not generating tau-paisr which will fail the visible Pt cuts applied on reconstruction level in physics analyses.
   //
   // NOTE: the thresholds specified by configuration parameter 'minVisibleTransverseMomentum' need to be a few GeV lower
   //       than the cuts applied on reconstruction level in physics analyses,
   //       to account for resolution effects 
   //
   if ( cfg.exists("minVisibleTransverseMomentum") ) {
     std::string minVisibleTransverseMomentumLine = cfg.getParameter<std::string>("minVisibleTransverseMomentum");
     const char* startptr = minVisibleTransverseMomentumLine.c_str();
     char* endptr;
     double d = strtod(startptr, &endptr);
     if ( *endptr == '\0' && endptr != startptr ) {
       // fallback for backwards compatibility: 
       // if it's a single number then use this as a threshold for both particles
       MinVisPtCut cutLeg1;
       cutLeg1.type_ = MinVisPtCut::kTAU;
       cutLeg1.threshold_ = d;
       cutLeg1.index_ = 0; 
       MinVisPtCut cutLeg2;
       cutLeg2.type_ = MinVisPtCut::kTAU;
       cutLeg2.threshold_ = d;
       cutLeg2.index_ = 1;
       MinVisPtCutCombination minVisPtCut;
       minVisPtCut.cut_string_ = minVisibleTransverseMomentumLine;
       minVisPtCut.cuts_.push_back(cutLeg1);
       minVisPtCut.cuts_.push_back(cutLeg2);
       minVisPtCuts_.push_back(minVisPtCut);
     } else {
       // string has new format: 
       // parse the minVisibleTransverseMomentum string
       for ( std::string::size_type prev = 0, pos = 0; prev < minVisibleTransverseMomentumLine.length(); prev = pos + 1) {
     pos = minVisibleTransverseMomentumLine.find(';', prev);
     if ( pos == std::string::npos ) pos = minVisibleTransverseMomentumLine.length();
     
     std::string sub = minVisibleTransverseMomentumLine.substr(prev, pos - prev);
     MinVisPtCutCombination minVisPtCut;
     minVisPtCut.cut_string_ = minVisibleTransverseMomentumLine;
     const char* sub_c = sub.c_str();
     while (*sub_c != '\0' ) {
       const char* sep = std::strchr(sub_c, '_');
       if ( sep == NULL ) throw cms::Exception("Configuration") 
         << "Minimum transverse parameter string must contain an underscore to separate type from Pt threshold !!\n";
       std::string type(sub_c, sep);
       
       MinVisPtCut cut;
       if      ( type == "elec1" ) { cut.type_ = MinVisPtCut::kELEC; cut.index_ = 0; }
       else if ( type == "mu1"   ) { cut.type_ = MinVisPtCut::kMU;   cut.index_ = 0; }
       else if ( type == "had1"  ) { cut.type_ = MinVisPtCut::kHAD;  cut.index_ = 0; }
       else if ( type == "tau1"  ) { cut.type_ = MinVisPtCut::kTAU;  cut.index_ = 0; }
       else if ( type == "elec2" ) { cut.type_ = MinVisPtCut::kELEC; cut.index_ = 1; }
       else if ( type == "mu2"   ) { cut.type_ = MinVisPtCut::kMU;   cut.index_ = 1; }
       else if ( type == "had2"  ) { cut.type_ = MinVisPtCut::kHAD;  cut.index_ = 1; }
       else if ( type == "tau2"  ) { cut.type_ = MinVisPtCut::kTAU;  cut.index_ = 1; }
       else throw cms::Exception("Configuration") 
         << "'" << type << "' is not a valid type. Allowed values are { elec1, mu1, had1, tau1, elec2, mu2, had2, tau2 } !!\n";
       
       char* endptr;
       cut.threshold_ = strtod(sep + 1, &endptr);
       if ( endptr == sep + 1 ) throw cms::Exception("Configuration") 
         << "No Pt threshold given !!\n";
       
       std::cout << "Adding vis. Pt cut: index = " << cut.index_ << ", type = " << cut.type_ << ", threshold = " << cut.threshold_ << std::endl;
       minVisPtCut.cuts_.push_back(cut);
       sub_c = endptr;
     }
     minVisPtCuts_.push_back(minVisPtCut);
       }
     }
   }
 
   rfRotationAngle_ = cfg.getParameter<double>("rfRotationAngle")*TMath::Pi()/180.;
   rfMirror_ = cfg.getParameter<bool>("rfMirror");
 
   std::string applyMuonRadiationCorrection_string = cfg.getParameter<std::string>("applyMuonRadiationCorrection");
   if ( applyMuonRadiationCorrection_string != "" ) {
     edm::ParameterSet cfgMuonRadiationAlgo;
     cfgMuonRadiationAlgo.addParameter<double>("beamEnergy", beamEnergy_);
     cfgMuonRadiationAlgo.addParameter<std::string>("mode", applyMuonRadiationCorrection_string);
     cfgMuonRadiationAlgo.addParameter<int>("verbosity", 0);
     edm::ParameterSet cfgPhotosOptions;  
     cfgMuonRadiationAlgo.addParameter<edm::ParameterSet>("PhotosOptions", cfgPhotosOptions);
     edm::ParameterSet cfgPythiaParameters = cfg.getParameter<edm::ParameterSet>("PythiaParameters");
     cfgMuonRadiationAlgo.addParameter<edm::ParameterSet>("PythiaParameters", cfgPythiaParameters);
     muonRadiationAlgo_ = new GenMuonRadiationAlgorithm(cfgMuonRadiationAlgo);
     applyMuonRadiationCorrection_ = true;
   }
 }

ParticleReplacerZtautau::~ParticleReplacerZtautau ( )

Definition at line 163 of file ParticleReplacerZtautau.cc.

References muonRadiationAlgo_.

 {
   delete muonRadiationAlgo_;
 }

Member Function Documentation

void ParticleReplacerZtautau::beginJob ( void )

virtual

Reimplemented from ParticleReplacerBase.

Definition at line 174 of file ParticleReplacerZtautau.cc.

References pythia_, and gen::Pythia6Service::setGeneralParams().

 {
   gen::Pythia6Service::InstanceWrapper pythia6InstanceGuard(&pythia_);
   pythia_.setGeneralParams();
 }

void ParticleReplacerZtautau::beginRun	(	edm::Run &	run,
		const edm::EventSetup &	es
	)

virtual

Reimplemented from ParticleReplacerBase.

Definition at line 699 of file ParticleReplacerZtautau.cc.

References gather_cfg::cout, gen::TauolaInterfaceBase::init(), tauola_, and tauola_isInitialized_.

 {
   if ( !tauola_isInitialized_ ) {
     std::cout << "<ParticleReplacerZtautau::beginRun>: Initializing TAUOLA interface." << std::endl;
     tauola_->init(es);
     tauola_isInitialized_ = true;
   }
 }

void ParticleReplacerZtautau::cleanEvent	(	HepMC::GenEvent *	genEvt,
		HepMC::GenVertex *	genVtx
	)

private

Definition at line 826 of file ParticleReplacerZtautau.cc.

References repairBarcodes().

Referenced by produce().

 {
   std::stack<HepMC::GenParticle*> genParticles_to_delete;
     
   std::stack<HepMC::GenVertex*> genVertices_to_process;
   std::stack<HepMC::GenVertex*> genVertices_to_delete;
 
   for ( HepMC::GenVertex::particles_out_const_iterator genParticle = genVtx->particles_out_const_begin();
     genParticle != genVtx->particles_out_const_end(); ++genParticle ) {
     genParticles_to_delete.push(*genParticle);
     if ( (*genParticle)->end_vertex() ) genVertices_to_process.push((*genParticle)->end_vertex());
   }
 
   while ( !genVertices_to_process.empty() ) {
     HepMC::GenVertex* tempVtx = genVertices_to_process.top();
     if ( tempVtx->particles_out_size() > 0 ) {
       for ( HepMC::GenVertex::particles_out_const_iterator genParticle = tempVtx->particles_out_const_begin();
         genParticle != tempVtx->particles_out_const_end(); ++genParticle ) {
     if ( (*genParticle)->end_vertex() ) genVertices_to_process.push((*genParticle)->end_vertex());
       }
       delete tempVtx;
     }
     genVertices_to_delete.push(tempVtx);
     genVertices_to_process.pop();
   }
     
   while ( !genVertices_to_delete.empty() ) {
     genEvt->remove_vertex(genVertices_to_delete.top());
     genVertices_to_delete.pop();
   }
 
   while ( !genParticles_to_delete.empty() ) {
     delete genVtx->remove_particle(genParticles_to_delete.top());
     genParticles_to_delete.pop();
   }
 
   repairBarcodes(genEvt);
 }

void ParticleReplacerZtautau::declareExtraProducts ( MCParticleReplacer * producer )

virtual

Reimplemented from ParticleReplacerBase.

Definition at line 168 of file ParticleReplacerZtautau.cc.

References MCParticleReplacer::call_produces().

 {
   producer->call_produces<ParticleCollection>("muonsBeforeRad");
   producer->call_produces<ParticleCollection>("muonsAfterRad");
 }

void ParticleReplacerZtautau::endJob ( void )

virtual

Reimplemented from ParticleReplacerBase.

Definition at line 708 of file ParticleReplacerZtautau.cc.

References gen::TauolaInterfaceBase::statistics(), and tauola_.

 {
   tauola_->statistics();
 }

HepMC::GenEvent* ParticleReplacerZtautau::processEventWithPythia ( HepMC::GenEvent * )

private

HepMC::GenEvent* ParticleReplacerZtautau::processEventWithTauola ( HepMC::GenEvent * )

private

std::auto_ptr< HepMC::GenEvent > ParticleReplacerZtautau::produce	(	const std::vector< reco::Particle > &	muons,
		const reco::Vertex *	evtVtx = `0`,
		const HepMC::GenEvent *	genEvt = `0`,
		MCParticleReplacer *	producer = `0`
	)

virtual

Implements ParticleReplacerBase.

Definition at line 234 of file ParticleReplacerZtautau.cc.

References funct::abs(), applyMuonRadiationCorrection_, assert(), beamEnergy_, MCParticleReplacer::call_put(), call_pyexec(), reco::Particle::charge(), cleanEvent(), GenMuonRadiationAlgorithm::compFSR(), conv, gather_cfg::cout, gen::TauolaInterfaceBase::decay(), decayRandomEngine, deltaR(), alignCSCRings::e, electronMass, edm::hlt::Exception, generatorMode_, GenParticle::GenParticle, edm::RandomNumberGenerator::getEngine(), MCParticleReplacer::getStreamID(), customizeTrackingMonitorSeedNumber::idx, edm::Service< T >::isAvailable(), maxNumberOfAttempts_, motherParticleID_, metsig::muon, muonMass, muonRadiationAlgo_, reco::Particle::p4(), ParticleReplacerBase::passed_, reco::Particle::pdgId(), protonMass, reco::Particle::px(), reco::Particle::py(), pythia_, reco::Particle::pz(), repairBarcodes(), gen::TauolaInterfaceBase::setRandomEngine(), reco::Particle::setStatus(), mathSSE::sqrt(), Clusterizer1DCommons::square(), targetParticle1AbsPdgID_, targetParticle1Mass_, targetParticle2AbsPdgID_, targetParticle2Mass_, tauMass, tauola_, testEvent(), transformationMode_, transformMuMu2LepLep(), transformMuMu2TauNu(), ParticleReplacerBase::tried_, ParticleReplacerBase::verbosity_, and reco::Particle::vertex().

 {
   edm::Service<edm::RandomNumberGenerator> rng;
   if ( !rng.isAvailable() ) 
     throw cms::Exception("Configuration")
       << "The RandomNumberProducer module requires the RandomNumberGeneratorService\n"
       << "which appears to be absent. Please add that service to your configuration\n"
       << "or remove the modules that require it.\n";
 
   CLHEP::HepRandomEngine& decayRandomEngine = rng->getEngine(producer->getStreamID());
   tauola_->setRandomEngine(&decayRandomEngine);
 
   if ( evtVtx != 0 ) throw cms::Exception("Configuration") 
     << "ParticleReplacerZtautau does NOT support using primary vertex as the origin for taus !!\n";
 
   std::auto_ptr<ParticleCollection> muonsBeforeRad(new ParticleCollection());
   std::auto_ptr<ParticleCollection> muonsAfterRad(new ParticleCollection());
 
 //--- transform the muons to the desired gen. particles
   std::vector<reco::Particle> embedParticles;   
   if ( transformationMode_ <= 2 ) { // mumu -> ll (Z -> Z boson, l = { e, mu, tau })
     
     if ( muons.size() != 2 ) {
       edm::LogError ("Replacer") 
     << "The decay mode Z->ll requires exactly two muons --> returning empty HepMC event !!" << std::endl;
       return std::auto_ptr<HepMC::GenEvent>(0);
     }
 
     switch ( transformationMode_ ) {
     case 0: // mumu -> mumu
       targetParticle1Mass_     = muonMass;
       targetParticle1AbsPdgID_ = 13;
       break;
     case 1: // mumu -> tautau     
       targetParticle1Mass_     = tauMass;
       targetParticle1AbsPdgID_ = 15;      
       break;
     case 2: // mumu -> ee   
       targetParticle1Mass_     = electronMass;
       targetParticle1AbsPdgID_ = 11;
       break;
     default:
       assert(0);
     }
     targetParticle2Mass_     = targetParticle1Mass_;
     targetParticle2AbsPdgID_ = targetParticle1AbsPdgID_;
     
     const reco::Particle& muon1 = muons.at(0);
     const reco::Particle& muon2 = muons.at(1);
     reco::Particle embedLepton1(muon1.charge(), muon1.p4(), muon1.vertex(), muon1.pdgId(), 0, true);
     reco::Particle embedLepton2(muon2.charge(), muon2.p4(), muon2.vertex(), muon2.pdgId(), 0, true);
     // Also call this for the mumu->mumu case, to set the correct status values
     // and to apply the rotation:
     transformMuMu2LepLep(decayRandomEngine, &embedLepton1, &embedLepton2);
     embedParticles.push_back(embedLepton1);
     embedParticles.push_back(embedLepton2);
   } else if ( transformationMode_ == 3 ) { // mumu -> taunu (Z -> W boson)
     
     if ( muons.size() != 2 ) {
       edm::LogError ("Replacer") 
     << "The decay mode W->taunu requires exactly two muons --> returning empty HepMC event !!" << std::endl;
       return std::auto_ptr<HepMC::GenEvent>(0);
     }
     
     targetParticle1Mass_     = tauMass;
     targetParticle1AbsPdgID_ = 15;   
     targetParticle2Mass_     = targetParticle1Mass_;
     targetParticle2AbsPdgID_ = targetParticle1AbsPdgID_;
 
     const reco::Particle& muon1 = muons.at(0);
     const reco::Particle& muon2 = muons.at(1);
     reco::Particle embedTau(muon1.charge(), muon1.p4(), muon1.vertex(), muon1.pdgId(), 0, true);
     reco::Particle embedNu(muon2.charge(), muon2.p4(), muon2.vertex(), muon2.pdgId(), 0, true);
     transformMuMu2TauNu(&embedTau, &embedNu);
     embedParticles.push_back(embedTau);
     embedParticles.push_back(embedNu);   
   } else if ( transformationMode_ == 4 ) { // munu -> taunu (W -> W boson)
     
     if ( muons.size() != 2 ) {
       edm::LogError ("Replacer") 
     << "The decay mode W->taunu requires exactly two gen. leptons --> returning empty HepMC event !!" << std::endl;
       return std::auto_ptr<HepMC::GenEvent>(0);
     }
 
     targetParticle1Mass_     = tauMass;
     targetParticle1AbsPdgID_ = 15;   
     targetParticle2Mass_     = 0.;
     targetParticle2AbsPdgID_ = 16; 
             
     const reco::Particle& muon = muons.at(0);
     double embedLeptonEn = sqrt(square(muon.px()) + square(muon.py()) + square(muon.pz()) + square(targetParticle1Mass_));
     reco::Candidate::LorentzVector embedTauP4(muon.px(), muon.py(), muon.pz(), embedLeptonEn);
     reco::Particle embedTau(muon.charge(), embedTauP4, muon.vertex(), targetParticle1AbsPdgID_*muon.pdgId()/std::abs(muon.pdgId()), 0, true);
     embedTau.setStatus(1);
     embedParticles.push_back(embedTau);
     const reco::Particle& nu = muons.at(1);
     reco::Particle embedNu(0, nu.p4(), nu.vertex(), -targetParticle2AbsPdgID_*muon.pdgId()/std::abs(muon.pdgId()), 0, true);
     embedNu.setStatus(1);
     embedParticles.push_back(embedNu);
   }
     
   if ( embedParticles.size() != 2 ){
     edm::LogError ("Replacer") 
       << "The creation of gen. particles failed somehow --> returning empty HepMC event !!" << std::endl;   
     return std::auto_ptr<HepMC::GenEvent>(0);
   }
 
   HepMC::GenEvent* genEvt_output = 0;
   
   HepMC::GenVertex* genVtx_output = new HepMC::GenVertex();
 
   HepMC::GenVertex* ppCollisionVtx = 0;
 
   std::vector<reco::Candidate::LorentzVector> auxPhotonP4s;
   
 //--- prepare the output HepMC event
   if ( genEvt ) { // embed gen. leptons into existing HepMC event
     genEvt_output = new HepMC::GenEvent(*genEvt);
     
     for ( HepMC::GenEvent::vertex_iterator genVtx = genEvt_output->vertices_begin(); 
       genVtx != genEvt_output->vertices_end(); ++genVtx ) {
       
       if ( (*genVtx)->particles_out_size() <= 0 || (*genVtx)->particles_in_size() <= 0 ) continue;
       
       bool foundMuon1 = false;
       bool foundMuon2 = false;
       bool foundZ     = false;
       for (  HepMC::GenVertex::particles_out_const_iterator genParticle = (*genVtx)->particles_out_const_begin(); 
         genParticle != (*genVtx)->particles_out_const_end(); ++genParticle ) {
     if ( (*genParticle)->pdg_id() ==  13 ) foundMuon1 = true;
     if ( (*genParticle)->pdg_id() == -13 ) foundMuon2 = true;
     if ( (*genParticle)->pdg_id() ==  23 ) foundZ     = true;
       }
       
       int motherPdgId = (*(*genVtx)->particles_in_const_begin())->pdg_id();
       
       if ( ((*genVtx)->particles_out_size() ==  2 && 
         (*genVtx)->particles_in_size()  >   0 &&
         motherPdgId                     == 23 && 
         foundMuon1                            &&
         foundMuon2                            ) ||
        ((*genVtx)->particles_out_size() >   2 &&
         (*genVtx)->particles_in_size()  >   0 &&
         motherPdgId                     == 23 && 
         foundMuon1                            &&
         foundMuon2                            &&
         foundZ                                ) ) {
     genVtx_output = (*genVtx);
       }
     }
     
     cleanEvent(genEvt_output, genVtx_output);
     
     // prevent a decay of existing particles
     // (the decay of existing particles is a bug in the PythiaInterface which should be fixed in newer versions) <-- to be CHECKed (*)
     for (  HepMC::GenEvent::particle_iterator genParticle = genEvt_output->particles_begin();
       genParticle != genEvt_output->particles_end(); ++genParticle ) {
       (*genParticle)->set_status(0);
     }
         
     for ( std::vector<reco::Particle>::const_iterator embedParticle = embedParticles.begin();
       embedParticle != embedParticles.end(); ++embedParticle ) {
       if ( applyMuonRadiationCorrection_ ) {
     reco::Candidate::LorentzVector sumOtherParticlesP4(0.,0.,0.,0.);
     for ( std::vector<reco::Particle>::const_iterator otherParticle = embedParticles.begin();
           otherParticle != embedParticles.end(); ++otherParticle ) {
       if ( deltaR(otherParticle->p4(), embedParticle->p4()) > 1.e-3 ) sumOtherParticlesP4 += otherParticle->p4();
     }
     int errorFlag = 0;
     reco::Candidate::LorentzVector muonFSR = muonRadiationAlgo_->compFSR(producer->getStreamID(), embedParticle->p4(), embedParticle->charge(), sumOtherParticlesP4, errorFlag);
     double embedParticlePx_corrected = embedParticle->px() + muonFSR.px();
     double embedParticlePy_corrected = embedParticle->py() + muonFSR.py();
     double embedParticlePz_corrected = embedParticle->pz() + muonFSR.pz();
     double embedParticleEn_corrected = sqrt(square(embedParticlePx_corrected) + square(embedParticlePy_corrected) + square(embedParticlePz_corrected) + square(embedParticle->mass()));
     reco::Candidate::LorentzVector embedParticleP4_corrected(embedParticlePx_corrected, embedParticlePy_corrected, embedParticlePz_corrected, embedParticleEn_corrected);
     genVtx_output->add_particle_out(new HepMC::GenParticle((HepMC::FourVector)embedParticleP4_corrected, embedParticle->pdgId(), 1, HepMC::Flow(), HepMC::Polarization(0,0)));
         // CV: add photon of energy matching muon FSR correction 
     //     in opposite eta, phi direction to preserve transverse momentum balance   
     auxPhotonP4s.push_back(reco::Candidate::LorentzVector(-muonFSR.px(), -muonFSR.py(), -muonFSR.pz(), sqrt(square(muonFSR.px()) + square(muonFSR.py()) + square(muonFSR.pz()))));
     // CV: assume pp collision vertex to be simply the first vertex;
     //     should not really matter as long as pointer is not null...
     ppCollisionVtx = (*genEvt_output->vertices_begin());
     assert(ppCollisionVtx);
     
     muonsBeforeRad->push_back(reco::Particle(embedParticle->charge(), embedParticle->p4(), embedParticle->vertex(), embedParticle->pdgId()));
     muonsAfterRad->push_back(reco::Particle(embedParticle->charge(), embedParticleP4_corrected, embedParticle->vertex(), embedParticle->pdgId()));
       } else {
     genVtx_output->add_particle_out(new HepMC::GenParticle((HepMC::FourVector)embedParticle->p4(), embedParticle->pdgId(), 1, HepMC::Flow(), HepMC::Polarization(0,0)));
       }
     }
   } else { // embed gen. leptons into new (empty) HepMC event
     reco::Particle::LorentzVector genMotherP4;
     double ppCollisionPosX = 0.;
     double ppCollisionPosY = 0.;
     double ppCollisionPosZ = 0.;
     int idx = 0;
     for ( std::vector<reco::Particle>::const_iterator embedParticle = embedParticles.begin();
       embedParticle != embedParticles.end(); ++embedParticle ) {
       //std::cout << "embedParticle #" << idx << ": Pt = " << embedParticle->pt() << "," 
       //      << " eta = " << embedParticle->eta() << ", phi = " << embedParticle->phi() << ", mass = " << embedParticle->mass() << std::endl;
       //std::cout << "(production vertex: x = " << embedParticle->vertex().x() << ", y = " << embedParticle->vertex().y() << ", z = " << embedParticle->vertex().z() << ")" << std::endl;
       genMotherP4 += embedParticle->p4();
       const reco::Particle::Point& embedParticleVertex = embedParticle->vertex();
       ppCollisionPosX += embedParticleVertex.x();
       ppCollisionPosY += embedParticleVertex.y();
       ppCollisionPosZ += embedParticleVertex.z();
       ++idx;
     }
     
     int numEmbedParticles = embedParticles.size();
     if ( numEmbedParticles > 0 ) {
       ppCollisionPosX /= numEmbedParticles;
       ppCollisionPosY /= numEmbedParticles;
       ppCollisionPosZ /= numEmbedParticles;
     }
     
     ppCollisionVtx = new HepMC::GenVertex(HepMC::FourVector(ppCollisionPosX*10., ppCollisionPosY*10., ppCollisionPosZ*10., 0.)); // convert from cm to mm
     double protonEn = beamEnergy_;
     double protonPz = sqrt(square(protonEn) - square(protonMass));
     ppCollisionVtx->add_particle_in(new HepMC::GenParticle(HepMC::FourVector(0., 0., +protonPz, protonEn), 2212, 3));
     ppCollisionVtx->add_particle_in(new HepMC::GenParticle(HepMC::FourVector(0., 0., -protonPz, protonEn), 2212, 3));
 
     HepMC::GenVertex* genMotherDecayVtx = new HepMC::GenVertex(HepMC::FourVector(ppCollisionPosX*10., ppCollisionPosY*10., ppCollisionPosZ*10., 0.)); // Z decays immediately
     HepMC::GenParticle* genMother = new HepMC::GenParticle((HepMC::FourVector)genMotherP4, motherParticleID_, (generatorMode_ == "Pythia" ? 3 : 2), HepMC::Flow(), HepMC::Polarization(0,0));
     if ( transformationMode_ == 3 ) {
       int chargedLepPdgId = embedParticles.begin()->pdgId(); // first daughter particle is charged lepton always
       int motherPdgId = -24*chargedLepPdgId/std::abs(chargedLepPdgId);
       genMother->set_pdg_id(motherPdgId);
     }
 
     ppCollisionVtx->add_particle_out(genMother);
 
     genMotherDecayVtx->add_particle_in(genMother);
     for ( std::vector<reco::Particle>::const_iterator embedParticle = embedParticles.begin();
       embedParticle != embedParticles.end(); ++embedParticle ) {
       if ( applyMuonRadiationCorrection_ ) {
     reco::Candidate::LorentzVector sumOtherParticlesP4(0.,0.,0.,0.);
     for ( std::vector<reco::Particle>::const_iterator otherParticle = embedParticles.begin();
           otherParticle != embedParticles.end(); ++otherParticle ) {
       if ( deltaR(otherParticle->p4(), embedParticle->p4()) > 1.e-3 ) sumOtherParticlesP4 += otherParticle->p4();
     }
     //std::cout << "embedParticle:" 
     //      << " En = " << embedParticle->energy() << "," 
     //      << " Px = " << embedParticle->px() << "," 
     //      << " Py = " << embedParticle->py() << "," 
     //      << " Pz = " << embedParticle->pz() << std::endl;
     int errorFlag = 0;
     reco::Candidate::LorentzVector muonFSR = muonRadiationAlgo_->compFSR(producer->getStreamID(), embedParticle->p4(), embedParticle->charge(), sumOtherParticlesP4, errorFlag);
     //std::cout << "muonFSR:" 
     //      << " En = " << muonFSR.E() << "," 
     //      << " Px = " << muonFSR.px() << "," 
     //      << " Py = " << muonFSR.py() << "," 
     //      << " Pz = " << muonFSR.pz() << std::endl;
     double embedParticlePx_corrected = embedParticle->px() + muonFSR.px();
     double embedParticlePy_corrected = embedParticle->py() + muonFSR.py();
     double embedParticlePz_corrected = embedParticle->pz() + muonFSR.pz();
     double embedParticleEn_corrected = sqrt(square(embedParticlePx_corrected) + square(embedParticlePy_corrected) + square(embedParticlePz_corrected) + square(embedParticle->mass()));
     reco::Candidate::LorentzVector embedParticleP4_corrected(embedParticlePx_corrected, embedParticlePy_corrected, embedParticlePz_corrected, embedParticleEn_corrected);
     //std::cout << "embedParticle (corrected):" 
     //      << " En = " << embedParticleP4_corrected.E() << "," 
     //      << " Px = " << embedParticleP4_corrected.px() << "," 
     //      << " Py = " << embedParticleP4_corrected.py() << "," 
     //      << " Pz = " << embedParticleP4_corrected.pz() << std::endl;
     genMotherDecayVtx->add_particle_out(new HepMC::GenParticle((HepMC::FourVector)embedParticleP4_corrected, embedParticle->pdgId(), 1, HepMC::Flow(), HepMC::Polarization(0,0)));
         // CV: add photon of energy matching muon FSR correction 
     //     in opposite eta, phi direction to preserve transverse momentum balance   
     auxPhotonP4s.push_back(reco::Candidate::LorentzVector(-muonFSR.px(), -muonFSR.py(), -muonFSR.pz(), sqrt(square(muonFSR.px()) + square(muonFSR.py()) + square(muonFSR.pz()))));
 
     muonsBeforeRad->push_back(reco::Particle(embedParticle->charge(), embedParticleP4_corrected, embedParticle->vertex(), embedParticle->pdgId()));
     muonsAfterRad->push_back(reco::Particle(embedParticle->charge(), embedParticle->p4(), embedParticle->vertex(), embedParticle->pdgId()));
       } else {
     genMotherDecayVtx->add_particle_out(new HepMC::GenParticle((HepMC::FourVector)embedParticle->p4(), embedParticle->pdgId(), 1, HepMC::Flow(), HepMC::Polarization(0,0)));
       }
     }
 
     genEvt_output = new HepMC::GenEvent();
     genEvt_output->add_vertex(ppCollisionVtx);
     genEvt_output->add_vertex(genMotherDecayVtx);
 
     repairBarcodes(genEvt_output);
   }
     
 //--- compute probability to pass visible Pt cuts
   HepMC::GenEvent* passedEvt_output = 0;
 
   unsigned int numEvents_tried  = 0;
   unsigned int numEvents_passed = 0;
     
   int verbosity_backup = verbosity_;
 
   HepMC::IO_HEPEVT conv;
   for ( int iTrial = 0; iTrial < maxNumberOfAttempts_; ++iTrial ) {
     HepMC::GenEvent* tempEvt = new HepMC::GenEvent(*genEvt_output);
     ++numEvents_tried;
     if ( generatorMode_ == "Pythia" )   { // Pythia
       throw cms::Exception("Configuration") 
     << "Pythia is currently not supported !!\n";
     } else if ( generatorMode_ == "Tauola" ) { // TAUOLA
       conv.write_event(tempEvt);
       HepMC::GenEvent* decayEvt = tauola_->decay(tempEvt);
       // This code only works if decay() modifies the event inplace. This seems
       // to have changed between CMSSW_5_3_X and CMSSW_7_0_0
       // (possible with the introduction of tauola++?), so make sure this
       // assumption is correct:
       assert(decayEvt == tempEvt);
     }
     
     bool passesVisPtCuts = testEvent(tempEvt);
     if ( passesVisPtCuts ) {
       if ( !passedEvt_output ) passedEvt_output = tempEvt; // store first HepMC event passing visible Pt cuts in output file
       else delete tempEvt;
       ++numEvents_passed;
       verbosity_ = 0;
     } else {
       delete tempEvt;
     }
   }
 
   tried_ = numEvents_tried;
   passed_ = numEvents_passed;
   verbosity_ = verbosity_backup;
   
   if ( !passedEvt_output ) {
     edm::LogError ("Replacer") 
       << "Failed to create an event which satisfies the visible Pt cuts !!" << std::endl;
     int idx = 0;
     for ( std::vector<reco::Particle>::const_iterator muon = muons.begin();
       muon != muons.end(); ++muon ) {
       std::cout << " muon #" << idx << " (charge = " << muon->charge() << "): Pt = " << muon->pt() << ", eta = " << muon->eta() << ", phi = " << muon->phi() << std::endl;
       ++idx;
     }
     return std::auto_ptr<HepMC::GenEvent>(0);
   }
 
   // use PYTHIA to decay unstable hadrons (e.g. pi0 -> gamma gamma)
   //std::cout << "before pi0 -> gamma gamma decays:" << std::endl;
   //passedEvt_output->print(std::cout); 
 
   conv.write_event(passedEvt_output);
 
   gen::Pythia6Service::InstanceWrapper pythia6InstanceGuard(&pythia_);
 
   // convert hepevt -> pythia
   call_pyhepc(2); 
 
   // call PYTHIA 
   call_pyexec();
  
   // convert pythia -> hepevt
   call_pyhepc(1); 
 
   HepMC::GenEvent* passedEvt_pythia = conv.read_next_event();
   //std::cout << "PYTHIA output:" << std::endl;
   //passedEvt_pythia->print(std::cout);
 
   // CV: back and forth conversion between HepMC and PYTHIA causes
   //     pp -> Z vertex to get corrupted for some reason;
   //     do **not** take HepMC::GenEvent from PYTHIA, 
   //     but add decays of unstable particles to original HepMC::GenEvent
   for ( HepMC::GenEvent::vertex_const_iterator genVertex_pythia = passedEvt_pythia->vertices_begin();
     genVertex_pythia != passedEvt_pythia->vertices_end(); ++genVertex_pythia ) {
     bool isDecayVertex = ((*genVertex_pythia)->particles_in_size() >= 1 && (*genVertex_pythia)->particles_out_size() >= 2);
     for ( HepMC::GenEvent::vertex_const_iterator genVertex_output = passedEvt_output->vertices_begin();
       genVertex_output != passedEvt_output->vertices_end(); ++genVertex_output ) {
       if ( matchesGenVertex(*genVertex_output, *genVertex_pythia, true, false) ) isDecayVertex = false;
     }
     if ( !isDecayVertex ) continue;
 
     // create new vertex
     //std::cout << "creating decay vertex: barcode = " << (*genVertex_pythia)->barcode() << std::endl;
     HepMC::GenVertex* genVertex_output = new HepMC::GenVertex((*genVertex_pythia)->position());
 
     // associate "incoming" particles to new vertex
     for ( HepMC::GenVertex::particles_in_const_iterator genParticle_pythia = (*genVertex_pythia)->particles_in_const_begin();
       genParticle_pythia != (*genVertex_pythia)->particles_in_const_end(); ++genParticle_pythia ) {
       for ( HepMC::GenEvent::particle_iterator genParticle_output = passedEvt_output->particles_begin();
         genParticle_output != passedEvt_output->particles_end(); ++genParticle_output ) {
     if ( matchesGenParticle(*genParticle_output, *genParticle_pythia) ) {
       //std::cout << " adding 'incoming' particle: barcode = " << (*genParticle_output)->barcode() << std::endl;
       genVertex_output->add_particle_in(*genParticle_output);
       // flag "incoming" particle to be unstable
       (*genParticle_output)->set_status(2);
     }
       }
     }
 
     // create "outgoing" particles and associate them to new vertex
     for ( HepMC::GenVertex::particles_out_const_iterator genParticle_pythia = (*genVertex_pythia)->particles_out_const_begin();
       genParticle_pythia != (*genVertex_pythia)->particles_out_const_end(); ++genParticle_pythia ) {
       HepMC::GenParticle* genParticle_output = new HepMC::GenParticle(
     (*genParticle_pythia)->momentum(), 
     (*genParticle_pythia)->pdg_id(), 
     (*genParticle_pythia)->status(), 
     (*genParticle_pythia)->flow(),  
     (*genParticle_pythia)->polarization());
       genParticle_output->suggest_barcode((*genParticle_pythia)->barcode());
       //std::cout << " adding 'outgoing' particle: barcode = " << genParticle_output->barcode() << std::endl;
       genVertex_output->add_particle_out(genParticle_output);
     }
 
     //std::cout << "adding decay vertex: barcode = " << genVertex_output->barcode() << std::endl;
     passedEvt_output->add_vertex(genVertex_output);
 
     // CV: add auxiliary photons correcting transverse momentum balance 
     //     in case corrections for muon --> muon + gamma radiation are applied
     //     after TAUOLA has run, in order not to confuse TAUOLA (polarization)
     if ( applyMuonRadiationCorrection_ ) {
       for ( std::vector<reco::Candidate::LorentzVector>::const_iterator auxPhotonP4 = auxPhotonP4s.begin();
         auxPhotonP4 != auxPhotonP4s.end(); ++auxPhotonP4 ) {
     ppCollisionVtx->add_particle_out(new HepMC::GenParticle((HepMC::FourVector)*auxPhotonP4, 22, 1, HepMC::Flow(), HepMC::Polarization(0,0)));
       }
     }
   }
   delete passedEvt_pythia;
 
   //std::cout << "after pi0 -> gamma gamma decays:" << std::endl;
   //passedEvt_output->print(std::cout);
 
   // undo the "hack" (*): 
   // recover the particle status codes
   if ( genEvt ) {
     for ( HepMC::GenEvent::particle_iterator genParticle = passedEvt_output->particles_begin();
       genParticle != passedEvt_output->particles_end(); ++genParticle ) {
       if ( (*genParticle)->end_vertex() ) (*genParticle)->set_status(2);
       else (*genParticle)->set_status(1);
     }
   }
 
   // check that transverse momentum of embedded Z -> tautau matches
   // transverse momentum of replaced di-muon system
   reco::Candidate::LorentzVector sumMuonP4_replaced(0.,0.,0.,0.);
   for ( std::vector<reco::Particle>::const_iterator muon = muons.begin();
     muon != muons.end(); ++muon ) {
     sumMuonP4_replaced += muon->p4();
   }
   reco::Candidate::LorentzVector sumMuonP4_embedded(0.,0.,0.,0.);
   if ( genEvt ) {
     for ( HepMC::GenEvent::particle_iterator genParticle = passedEvt_output->particles_begin();
       genParticle != passedEvt_output->particles_end(); ++genParticle ) {
       if ( (*genParticle)->status() != 1 ) continue;
       if ( abs((*genParticle)->pdg_id()) == 12 || abs((*genParticle)->pdg_id()) == 14 || abs((*genParticle)->pdg_id()) == 16 ) continue;
       sumMuonP4_embedded += reco::Candidate::LorentzVector((*genParticle)->momentum().px(), (*genParticle)->momentum().py(), (*genParticle)->momentum().pz(), (*genParticle)->momentum().e());
     }
   }
   if ( fabs(sumMuonP4_embedded.pt() - sumMuonP4_replaced.pt()) > (1.e-3*sumMuonP4_replaced.pt()) ) {
     edm::LogWarning ("<MCEmbeddingValidationAnalyzer::analyze>")
       << "Transverse momentum of embedded tau leptons = " << sumMuonP4_embedded.pt() 
       << " differs from transverse momentum of replaced muons = " << sumMuonP4_replaced.pt() << " !!" << std::endl;
   }
 
   std::auto_ptr<HepMC::GenEvent> passedEvt_output_ptr(passedEvt_output);    
   if ( verbosity_ ) {
     passedEvt_output_ptr->print(std::cout);
     std::cout << " numEvents: tried = " << numEvents_tried << ", passed = " << numEvents_passed << std::endl;
   }
 
   delete genVtx_output;
   delete genEvt_output;
   
   producer->call_put(muonsBeforeRad, "muonsBeforeRad");
   producer->call_put(muonsAfterRad, "muonsAfterRad");
 
   return passedEvt_output_ptr;
 }

bool ParticleReplacerZtautau::testEvent ( HepMC::GenEvent * genEvt )

private

Definition at line 713 of file ParticleReplacerZtautau.cc.

References funct::abs(), assert(), runEdmFileComparison::collection, gather_cfg::cout, GOODCOLL_filter_cfg::cut, GenParticle::GenParticle, ParticleReplacerZtautau::MinVisPtCut::kELEC, ParticleReplacerZtautau::MinVisPtCut::kHAD, ParticleReplacerZtautau::MinVisPtCut::kMU, ParticleReplacerZtautau::MinVisPtCut::kTAU, minVisPtCuts_, python.multivaluedict::sort(), AlCaHLTBitMon_QueryRunRegistry::string, and ParticleReplacerBase::verbosity_.

Referenced by produce().

 {
   //if ( verbosity_ ) std::cout << "<ParticleReplacerZtautau::testEvent>:" << std::endl;
 
   if ( minVisPtCuts_.empty() ) return true; // no visible Pt cuts applied
 
   std::vector<double> muonPts;
   std::vector<double> electronPts;
   std::vector<double> tauJetPts;
   std::vector<double> tauPts;
 
   int genParticleIdx = 0;
   for ( HepMC::GenEvent::particle_iterator genParticle = genEvt->particles_begin();
     genParticle != genEvt->particles_end(); ++genParticle ) {
     if ( abs((*genParticle)->pdg_id()) == 15 && (*genParticle)->end_vertex() ) {
       reco::Candidate::LorentzVector visP4;
       std::queue<const HepMC::GenParticle*> decayProducts;
       decayProducts.push(*genParticle);
       enum { kELEC, kMU, kHAD };
       int type = kHAD;
       int decayProductIdx = 0;
       while ( !decayProducts.empty() && decayProductIdx < 100 ) { // CV: protection against entering infinite loop in case of corrupt particle relations
     const HepMC::GenParticle* decayProduct = decayProducts.front();
     if ( verbosity_ ) {
       std::cout << "decayProduct #" << (decayProductIdx + 1) << " (pdgId = " << decayProduct->pdg_id() << "):" 
             << " Pt = " << decayProduct->momentum().perp() << ", eta = " << decayProduct->momentum().eta() << ", phi = " << decayProduct->momentum().phi() 
             << std::endl;
     }
     decayProducts.pop();
     if ( !decayProduct->end_vertex() ) { // stable decay product
       int absPdgId = abs(decayProduct->pdg_id());
       if ( !(absPdgId == 12 || absPdgId == 14 || absPdgId == 16) ) visP4 += (reco::Candidate::LorentzVector)decayProduct->momentum();
           if ( absPdgId == 11 ) type = kELEC;
       if ( absPdgId == 13 ) type = kMU;
     } else { // decay product decays further...
       HepMC::GenVertex* decayVtx = decayProduct->end_vertex();
       for ( HepMC::GenVertex::particles_out_const_iterator daughter = decayVtx->particles_out_const_begin();
         daughter != decayVtx->particles_out_const_end(); ++daughter ) {
         decayProducts.push(*daughter);
       }
     }
     ++decayProductIdx;
       }
 
       double visPt = visP4.pt();
       tauPts.push_back(visPt);
       if      ( type == kMU   ) muonPts.push_back(visPt);
       else if ( type == kELEC ) electronPts.push_back(visPt);
       else if ( type == kHAD  ) tauJetPts.push_back(visPt);
       if ( verbosity_ ) {
         std::string type_string = "";
         if      ( type == kMU   ) type_string = "mu";
         else if ( type == kELEC ) type_string = "elec";
         else if ( type == kHAD  ) type_string = "had";
         std::cout << "visLeg #" << (genParticleIdx + 1) << " (type = " << type_string << "):" 
           << " Pt = " << visP4.pt() << ", eta = " << visP4.eta() << ", phi = " << visP4.phi() 
           << " (X = " << (visP4.energy()/(*genParticle)->momentum().e()) << ")" << std::endl;
       }
       ++genParticleIdx;
     }
   }
 
   std::sort(tauPts.begin(), tauPts.end(), std::greater<double>());
   std::sort(electronPts.begin(), electronPts.end(), std::greater<double>());
   std::sort(muonPts.begin(), muonPts.end(), std::greater<double>());
   std::sort(tauJetPts.begin(), tauJetPts.end(), std::greater<double>());
     
   // check if visible decay products pass Pt cuts
   //
   // NOTE: return value = True if leg1 > threshold[i] && leg2 > threshold[i] for **any** path i
   //      (e.g. (leg1Pt > 10 && leg2Pt > 20) || (leg1Pt > 20 && leg2Pt > 10), consistent with logic used by HLT)
   //
   for ( std::vector<MinVisPtCutCombination>::const_iterator minVisPtCut = minVisPtCuts_.begin();
     minVisPtCut != minVisPtCuts_.end(); ++minVisPtCut ) {
     //if ( verbosity_ ) minVisPtCut->print(std::cout);
     
     bool passesMinVisCut = true;
     
     for ( std::vector<MinVisPtCut>::const_iterator cut = minVisPtCut->cuts_.begin();
       cut != minVisPtCut->cuts_.end(); ++cut ) {
       std::vector<double>* collection = 0;
       switch ( cut->type_ ) {
       case MinVisPtCut::kELEC:
     collection = &electronPts; 
     break;
       case MinVisPtCut::kMU: 
     collection = &muonPts; 
     break;
       case MinVisPtCut::kHAD: 
     collection = &tauJetPts; 
     break;
       case MinVisPtCut::kTAU: 
     collection = &tauPts; 
     break;
       }
       assert(collection);
       
       // j-th tau decay product fails visible Pt cut
       if ( cut->index_ >= collection->size() || (*collection)[cut->index_] < cut->threshold_ ) {
     passesMinVisCut = false;
     break;
       }
     }
 
     // all tau decay products satisfy visible Pt cuts for i-th path 
     //if ( verbosity_ ) std::cout << "passes vis. Pt cuts = " << passesMinVisCut << std::endl;
     if ( passesMinVisCut ) return true;
   }
 
   // visible Pt cuts failed for all paths
   return false;
 }

void ParticleReplacerZtautau::transformMuMu2LepLep	(	CLHEP::HepRandomEngine &	randomEngine,
		reco::Particle *	muon1,
		reco::Particle *	muon2
	)

private

Definition at line 912 of file ParticleReplacerZtautau.cc.

References funct::abs(), beamEnergy_, gather_cfg::cout, alignCSCRings::e, reco::Particle::p4(), reco::Particle::pdgId(), Pi, reco::print(), protonMass, EnergyCorrector::pt, rfMirror_, rfRotationAngle_, svgfig::rotate(), reco::Particle::setP4(), reco::Particle::setPdgId(), reco::Particle::setStatus(), mathSSE::sqrt(), Clusterizer1DCommons::square(), targetParticle1AbsPdgID_, targetParticle1Mass_, targetParticle2AbsPdgID_, targetParticle2Mass_, and ParticleReplacerBase::verbosity_.

Referenced by produce().

 {
 //--- transform a muon pair into an electron/tau pair,
 //    taking into account the difference between muon and electron/tau mass
 
   reco::Particle::LorentzVector muon1P4_lab = muon1->p4();
   reco::Particle::LorentzVector muon2P4_lab = muon2->p4();
   reco::Particle::LorentzVector zP4_lab = muon1P4_lab + muon2P4_lab;
 
   ROOT::Math::Boost boost_to_rf(zP4_lab.BoostToCM());
   ROOT::Math::Boost boost_to_lab(boost_to_rf.Inverse());
 
   reco::Particle::LorentzVector zP4_rf = boost_to_rf(zP4_lab);
 
   reco::Particle::LorentzVector muon1P4_rf = boost_to_rf(muon1P4_lab);
   reco::Particle::LorentzVector muon2P4_rf = boost_to_rf(muon2P4_lab);
 
   if ( verbosity_ ) {
     std::cout << "before rotation:" << std::endl;
     print("muon1(lab)", muon1P4_lab, &zP4_lab);
     print("muon2(lab)", muon2P4_lab, &zP4_lab);
     print("Z(lab)", zP4_lab);
     print("muon1(rf)", muon1P4_rf, &zP4_lab);
     print("muon2(rf)", muon2P4_rf, &zP4_lab);
     print("Z(rf)", zP4_rf);
   }
 
   if ( rfRotationAngle_ != 0. ) {
     double rfRotationAngle_value = rfRotationAngle_;
     if ( rfRotationAngle_ == -1. ) {
       double u = randomEngine.flat();
       rfRotationAngle_value = 2.*TMath::Pi()*u;
     }
 
     muon1P4_rf = rotate(muon1P4_rf, zP4_lab, rfRotationAngle_value);
     muon2P4_rf = rotate(muon2P4_rf, zP4_lab, rfRotationAngle_value);
   }
 
   if ( rfMirror_ ) {
     double protonEn = beamEnergy_;
     double protonPz = sqrt(square(protonEn) - square(protonMass));
     const reco::Particle::LorentzVector pplus_lab(0., 0., protonPz, protonEn);
     const reco::Particle::LorentzVector pplus_rf = boost_to_rf(pplus_lab);
 
     muon1P4_rf = mirror(muon1P4_rf, zP4_lab, pplus_rf);
     muon2P4_rf = mirror(muon2P4_rf, zP4_lab, pplus_rf); 
   }
 
   double muon1P_rf2 = square(muon1P4_rf.px()) + square(muon1P4_rf.py()) + square(muon1P4_rf.pz());
   double lep1Mass2 = square(targetParticle1Mass_);
   double lep1En_rf = 0.5*zP4_rf.E();
   double lep1P_rf2  = square(lep1En_rf) - lep1Mass2;
   if ( lep1P_rf2 < 0. ) lep1P_rf2 = 0.;
   float scaleFactor1 = sqrt(lep1P_rf2/muon1P_rf2);
   reco::Particle::LorentzVector lep1P4_rf = reco::Particle::LorentzVector(
     scaleFactor1*muon1P4_rf.px(), scaleFactor1*muon1P4_rf.py(), scaleFactor1*muon1P4_rf.pz(), lep1En_rf);
 
   double muon2P_rf2 = square(muon2P4_rf.px()) + square(muon2P4_rf.py()) + square(muon2P4_rf.pz());
   double lep2Mass2 = square(targetParticle2Mass_);
   double lep2En_rf = 0.5*zP4_rf.E();
   double lep2P_rf2  = square(lep2En_rf) - lep2Mass2;
   if ( lep2P_rf2 < 0. ) lep2P_rf2 = 0.;
   float scaleFactor2 = sqrt(lep2P_rf2/muon2P_rf2);
   reco::Particle::LorentzVector lep2P4_rf = reco::Particle::LorentzVector(
     scaleFactor2*muon2P4_rf.px(), scaleFactor2*muon2P4_rf.py(), scaleFactor2*muon2P4_rf.pz(), lep2En_rf);
 
   reco::Particle::LorentzVector lep1P4_lab = boost_to_lab(lep1P4_rf);
   reco::Particle::LorentzVector lep2P4_lab = boost_to_lab(lep2P4_rf);
 
   if ( verbosity_ ) {
     std::cout << "after rotation:" << std::endl;
     print("lep1(rf)", muon1P4_rf, &zP4_lab);
     print("lep2(rf)", muon2P4_rf, &zP4_lab);    
     reco::Particle::LorentzVector lep1p2_lab = lep1P4_lab + lep2P4_lab;
     print("lep1(lab)", lep1P4_lab, &zP4_lab);
     print("lep2(lab)", lep2P4_lab, &zP4_lab);    
     print("lep1+2(lab)", lep1p2_lab);
   }
 
   // perform additional checks:
   // the following tests guarantee a deviation of less than 0.1% 
   // for the following values of the original muons and the embedded electrons/taus in terms of:
   //  - invariant mass
   //  - transverse momentum
   if ( !(fabs(zP4_lab.mass() - (lep1P4_lab + lep2P4_lab).mass()) < (1.e-3*zP4_lab.mass()) &&
      fabs(zP4_lab.pt()   - (lep1P4_lab + lep2P4_lab).pt())   < (1.e-3*zP4_lab.pt())) ) 
     edm::LogError ("ParticleReplacerZtautau") 
       << "The kinematics of muons and embedded electrons/taus differ by more than 0.1%:" << std::endl 
       << " mass(muon1 + muon2) = " << zP4_lab.mass() << ", mass(lep1 + lep2) = " << (lep1P4_lab + lep2P4_lab).mass() << std::endl
       << " Pt(muon1 + muon2) = " << zP4_lab.pt() << ", Pt(lep1 + lep2) = " << (lep1P4_lab + lep2P4_lab).pt() << " --> please CHECK !!" << std::endl;
   
   muon1->setP4(lep1P4_lab);
   muon2->setP4(lep2P4_lab);
 
   muon1->setPdgId(targetParticle1AbsPdgID_*muon1->pdgId()/abs(muon1->pdgId())); 
   muon2->setPdgId(targetParticle2AbsPdgID_*muon2->pdgId()/abs(muon2->pdgId()));
 
   muon1->setStatus(1);
   muon2->setStatus(1);
 
   return;
 }

void ParticleReplacerZtautau::transformMuMu2TauNu	(	reco::Particle *	muon1,
		reco::Particle *	muon2
	)

private

Definition at line 1015 of file ParticleReplacerZtautau.cc.

References funct::abs(), assert(), breitWignerWidthW, breitWignerWidthZ, alignCSCRings::e, nomMassW, nomMassZ, reco::Particle::p4(), reco::Particle::pdgId(), phi, EnergyCorrector::pt, reco::Particle::setP4(), reco::Particle::setPdgId(), reco::Particle::setStatus(), mathSSE::sqrt(), Clusterizer1DCommons::square(), targetParticle1AbsPdgID_, targetParticle1Mass_, targetParticle2AbsPdgID_, targetParticle2Mass_, and theta().

Referenced by produce().

 {
 //--- transform a muon pair into tau + nu (replacing a Z by W boson)
 
   reco::Particle::LorentzVector muon1P4_lab = muon1->p4();
   reco::Particle::LorentzVector muon2P4_lab = muon2->p4();
   reco::Particle::LorentzVector zP4_lab = muon1P4_lab + muon2P4_lab;
 
   ROOT::Math::Boost boost_to_rf(zP4_lab.BoostToCM());
   ROOT::Math::Boost boost_to_lab(boost_to_rf.Inverse());
 
   reco::Particle::LorentzVector zP4_rf = boost_to_rf(zP4_lab);
   
   double wMass = (zP4_rf.mass() - nomMassZ)*(breitWignerWidthW/breitWignerWidthZ) + nomMassW;
 
   reco::Particle::LorentzVector muon1P4_rf = boost_to_rf(muon1P4_lab);
   reco::Particle::LorentzVector muon2P4_rf = boost_to_rf(muon2P4_lab);
   
   double muon1P_rf2 = square(muon1P4_rf.px()) + square(muon1P4_rf.py()) + square(muon1P4_rf.pz());
   double tauMass2 = square(targetParticle1Mass_);
   double tauEn_rf = 0.5*zP4_rf.E();
   double tauP_rf2  = square(tauEn_rf) - tauMass2;
   if ( tauP_rf2 < 0. ) tauP_rf2 = 0.;
   float scaleFactor1 = sqrt(tauP_rf2/muon1P_rf2)*(wMass/zP4_rf.mass());
   reco::Particle::LorentzVector tauP4_rf = reco::Particle::LorentzVector(
     scaleFactor1*muon1P4_rf.px(), scaleFactor1*muon1P4_rf.py(), scaleFactor1*muon1P4_rf.pz(), tauEn_rf);
 
   double muon2P_rf2 = square(muon2P4_rf.px()) + square(muon2P4_rf.py()) + square(muon2P4_rf.pz());
   double nuMass2 = square(targetParticle2Mass_);
   assert(nuMass2 < 1.e-4);
   double nuEn_rf = 0.5*zP4_rf.E();
   double nuP_rf2  = square(nuEn_rf) - nuMass2;
   if ( nuP_rf2 < 0. ) nuP_rf2 = 0.;
   float scaleFactor2 = sqrt(nuP_rf2/muon2P_rf2)*(wMass/zP4_rf.mass());
   reco::Particle::LorentzVector nuP4_rf = reco::Particle::LorentzVector(
     scaleFactor2*muon2P4_rf.px(), scaleFactor2*muon2P4_rf.py(), scaleFactor2*muon2P4_rf.pz(), nuEn_rf);
   
   reco::Particle::LorentzVector tauP4_lab = boost_to_lab(tauP4_rf);
   reco::Particle::LorentzVector nuP4_lab = boost_to_lab(nuP4_rf);
 
   // perform additional checks:
   // the following tests guarantee a deviation of less than 0.1% 
   // for the following values of the original muons and the embedded electrons/taus in terms of:
   //  - theta
   //  - phi
   if ( !(std::abs(zP4_lab.theta() - (tauP4_lab + nuP4_lab).theta())/zP4_lab.theta() < 1.e-3 &&
      std::abs(zP4_lab.phi()   - (tauP4_lab + nuP4_lab).phi())/zP4_lab.phi()     < 1.e-3) ) 
     edm::LogError ("Replacer") 
       << "The kinematics of muons and embedded tau/neutrino differ by more than 0.1%:" << std::endl 
       << " mass(muon1 + muon2) = " << zP4_lab.mass() << ", mass(lep1 + lep2) = " << (tauP4_lab + nuP4_lab).mass() << std::endl
       << " Pt(muon1 + muon2) = " << zP4_lab.pt() << ", Pt(lep1 + lep2) = " << (tauP4_lab + nuP4_lab).pt() << " --> please CHECK !!" << std::endl;
 
   muon1->setP4(tauP4_lab);
   muon2->setP4(nuP4_lab);
 
   muon1->setPdgId(targetParticle1AbsPdgID_*muon1->pdgId()/abs(muon1->pdgId())); 
   muon2->setPdgId(targetParticle2AbsPdgID_*muon2->pdgId()/abs(muon2->pdgId()));
 
   muon1->setStatus(1);
   muon2->setStatus(1);
 
   return;
 }