TestParticleFactory Class Reference

This is a class, which generates DataStore particles, according to the provided decay string e.g. More...

#include <TestParticleFactory.h>

Public Member Functions
const Belle2::Particle *	produceParticle (const std::string &decayString, const ROOT::Math::PxPyPzEVector &momentum, const ROOT::Math::XYZVector &vertex)
	Main method to produce particles.
Belle2::Particle::EParticleSourceObject	getType (const Belle2::DecayDescriptorParticle *particleDescription)
	Helper method to get EParticleSourceObject from PDG code.
const Belle2::Particle *	createParticle (const Belle2::DecayDescriptor *particleDescriptor, const ROOT::Math::PxPyPzEVector &momentum, const ROOT::Math::XYZVector &vertex)
	This method is used for recursion.
const Belle2::Particle *	createPhoton (const ROOT::Math::PxPyPzEVector &momentum)
	Creates different photons for tests.
const Belle2::Particle *	createCharged (const Belle2::DecayDescriptor *particleDescriptor, const ROOT::Math::PxPyPzEVector &momentum, const ROOT::Math::XYZVector &vertex)
	Creates different charged particles for tests.

Private Attributes
int	m_photonIndex
	Used to differentiate photons from one another.

Detailed Description

This is a class, which generates DataStore particles, according to the provided decay string e.g.

"^K_S0 -> ^pi+ ^pi-". All particles are added to Belle2::StoreArray<Belle2::Particle> It is primarily used in the ROE tests.

Definition at line 27 of file TestParticleFactory.h.

Constructor & Destructor Documentation

TestParticleFactory()

TestParticleFactory ( )

inline

Definition at line 29 of file TestParticleFactory.h.

: m_photonIndex(0) {};

~TestParticleFactory()

~TestParticleFactory ( )

inline

Definition at line 30 of file TestParticleFactory.h.

{};

Member Function Documentation

createCharged()

const Belle2::Particle * createCharged ( const Belle2::DecayDescriptor * particleDescriptor, const ROOT::Math::PxPyPzEVector & momentum, const ROOT::Math::XYZVector & vertex )

inline

Creates different charged particles for tests.

Definition at line 138 of file TestParticleFactory.h.

    {
      auto* particleDescription = particleDescriptor->getMother();
      ROOT::Math::XYZVector tmomentum(momentum.X(), momentum.Y(), momentum.Z());
      const float pValue = 0.5;
      const float bField = 1.5;
      TMatrixDSym cov6(6);
      int chargefactor = (abs(particleDescription->getPDGCode()) == Belle2::Const::electron.getPDGCode()
                          || abs(particleDescription->getPDGCode()) == Belle2::Const::muon.getPDGCode()) ? -1 : 1;
      const int charge = (particleDescription->getPDGCode()) / abs(particleDescription->getPDGCode()) * chargefactor;
      unsigned long long int CDCValue = static_cast<unsigned long long int>(0x300000000000000);
      Belle2::StoreArray<Belle2::TrackFitResult> myTrackFits;
      Belle2::StoreArray<Belle2::Track> myTracks;
      myTrackFits.appendNew(vertex, tmomentum, cov6, charge, Belle2::Const::ChargedStable(abs(particleDescription->getPDGCode())), pValue,
                            bField,
                            CDCValue, 16777215, 0);
      Belle2::Track mytrack;
      Belle2::StoreArray<Belle2::Particle> myParticles;
      mytrack.setTrackFitResultIndex(Belle2::Const::ChargedStable(abs(particleDescription->getPDGCode())), myTrackFits.getEntries() - 1);
      Belle2::Track* savedTrack = myTracks.appendNew(mytrack);
      Belle2::Particle* part = myParticles.appendNew(savedTrack, Belle2::Const::ChargedStable(abs(particleDescription->getPDGCode())));
      B2INFO("\tParticle PDG: " << part->getPDGCode() << " charge: " << part->getCharge()  << " charge: " << charge << " momentum: " <<
             part->getMomentumMagnitude() << " index: " << part->getArrayIndex());
      return part;
    }

createParticle()

const Belle2::Particle * createParticle ( const Belle2::DecayDescriptor * particleDescriptor, const ROOT::Math::PxPyPzEVector & momentum, const ROOT::Math::XYZVector & vertex )

inline

This method is used for recursion.

Definition at line 81 of file TestParticleFactory.h.

    {
      Belle2::Particle::EParticleSourceObject type = getType(particleDescriptor->getMother());
      if (type == Belle2::Particle::EParticleSourceObject::c_Track) {
        return createCharged(particleDescriptor, momentum, vertex);
      }
      if (type == Belle2::Particle::EParticleSourceObject::c_ECLCluster) {
        return createPhoton(momentum);
      }
      Belle2::StoreArray<Belle2::Particle> myParticles;
      //Create composite particle:
      auto* motherDescriptor = particleDescriptor->getMother();
      B2INFO("Mother PDG: " << motherDescriptor->getPDGCode() << " selected: " << motherDescriptor->isSelected() << " name: " <<
             motherDescriptor->getNameSimple());
      unsigned int nDaughters = particleDescriptor->getNDaughters();
      Belle2::Particle mother(momentum, motherDescriptor->getPDGCode());
      for (unsigned int i = 0; i < nDaughters; i++) {
        auto* daughter = particleDescriptor->getDaughter(i)->getMother();
        B2INFO("\tDaughter PDG: " << daughter->getPDGCode() << " selected: " << daughter->isSelected() << " name: " <<
               daughter->getNameSimple());
        auto* daughterParticle = createParticle(particleDescriptor->getDaughter(i), momentum, vertex);
        mother.appendDaughter(daughterParticle);
      }
      auto* result = myParticles.appendNew(mother);
      return result;
    };

createPhoton()

const Belle2::Particle * createPhoton ( const ROOT::Math::PxPyPzEVector & momentum )

inline

Creates different photons for tests.

Definition at line 112 of file TestParticleFactory.h.

    {
      Belle2::StoreArray<Belle2::ECLCluster> myECLClusters;
      Belle2::StoreArray<Belle2::Particle> myParticles;
      Belle2::ECLCluster myECL;
      myECL.setIsTrack(false);
      //TRandom3 generator;
      myECL.setConnectedRegionId(m_photonIndex++);
      myECL.setEnergy(momentum.E());
      myECL.setHypothesis(Belle2::ECLCluster::EHypothesisBit::c_nPhotons);
      //This is necessary to avoid isCopyOf == true for Belle2::ECLClusters:
      myECL.setClusterId(m_photonIndex++);
      Belle2::ECLCluster* savedECL = myECLClusters.appendNew(myECL);
 
      Belle2::Particle p(savedECL);
      Belle2::Particle* part = myParticles.appendNew(p);
      B2INFO("\tParticle PDG: " << part->getPDGCode() << " charge: " << part->getCharge()  << " momentum: " <<
             part->getMomentumMagnitude() << " index: " << part->getArrayIndex() << " eclindex: " << part->getECLCluster()->getArrayIndex()
             << " theta: " << part->getECLCluster()->getTheta());
      return part;
    }

getType()

Belle2::Particle::EParticleSourceObject getType ( const Belle2::DecayDescriptorParticle * particleDescription )

inline

Helper method to get EParticleSourceObject from PDG code.

Definition at line 64 of file TestParticleFactory.h.

    {
      int pdg = abs(particleDescription->getPDGCode());
      if (pdg == Belle2::Const::pion.getPDGCode() || pdg == Belle2::Const::electron.getPDGCode()
          || pdg == Belle2::Const::kaon.getPDGCode() || pdg == Belle2::Const::muon.getPDGCode()
          || pdg == Belle2::Const::proton.getPDGCode()) {
        return Belle2::Particle::EParticleSourceObject::c_Track;
      }
      if (pdg == Belle2::Const::photon.getPDGCode()) {
        return Belle2::Particle::EParticleSourceObject::c_ECLCluster;
      }
      return Belle2::Particle::EParticleSourceObject::c_Composite;
    }

produceParticle()

const Belle2::Particle * produceParticle ( const std::string & decayString, const ROOT::Math::PxPyPzEVector & momentum, const ROOT::Math::XYZVector & vertex )

inline

Main method to produce particles.

For simplification, all particles are created with the same momentum and decay vertex. If for example "^K_S0 -> ^pi+ ^pi-" decay string is provided as an argument, the factory will produce two daughter pions with opposite charges first, and then these pions will be used to form mother K_S0 particle which will be returned. The decay string can have any complexity and all PDG codes of allowed and charges will be respected.

Definition at line 41 of file TestParticleFactory.h.

    {
      Belle2::DecayDescriptor* decaydescriptor = new Belle2::DecayDescriptor();
      bool isString = decaydescriptor->init(decayString);
      if (!isString) {
        B2INFO("Decay string is not defined: " << decayString);
        delete decaydescriptor;
        return nullptr;
      }
      std::vector<std::string> strNames = decaydescriptor->getSelectionNames();
      for (auto& name : strNames) {
        B2INFO("Creation of particle: " << name);
      }
      // Recursive function
      auto* result = createParticle(decaydescriptor, momentum, vertex);
      delete decaydescriptor;
      return result;
    };

Member Data Documentation

m_photonIndex

int m_photonIndex

private

Used to differentiate photons from one another.

Definition at line 166 of file TestParticleFactory.h.

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The documentation for this class was generated from the following file:

• analysis/tests/utilities/TestParticleFactory.h