EvtGenInterface Class Reference

Class to interface EvtGen. More...

#include <EvtGenInterface.h>

Collaboration diagram for EvtGenInterface:

Public Member Functions
	EvtGenInterface ()
	Constructor.
	~EvtGenInterface ()
	Destructor.
int	setup (const std::string &decayFileName, const std::string &parentParticle, const std::string &userFileName=std::string(""), bool coherentMixing=true)
	Setup evtgen with the given decay files
int	simulateEvent (MCParticleGraph &graph, TLorentzVector pParentParticle, TVector3 pPrimaryVertex, int inclusiveType, const std::string &inclusiveParticle)
	Generate a single event.
int	simulateDecay (MCParticleGraph &graph, MCParticleGraph::GraphParticle &parent)
	Simulate a particle decay.

Static Public Member Functions
static EvtGen *	createEvtGen (const std::string &decayFileName, bool coherentMixing)
	Create and initialize an EvtGen instance: More...

Protected Attributes
EvtParticle *	m_parent
	Variable needed for parent particle. More...
EvtGen *	m_Generator
	Variable needed for EvtGen generator.
EvtVector4R	m_pinit
	Variable needed for initial momentum.
EvtId	m_ParentParticle
	Variable needed for parent particle ID.
bool	m_ParentInitialized
	Whether parent particle is initialized.
IOIntercept::OutputToLogMessages	m_logCapture
	Capture evtgen log and transform into basf2 logging.

Static Protected Attributes
static EvtGenFwRandEngine	m_eng
	Variable needed for random generator.

Private Member Functions
int	addParticles2Graph (EvtParticle *particle, MCParticleGraph &graph, TVector3 pPrimaryVertex, MCParticleGraph::GraphParticle *parent, double timeOffset=0)
	Convert EvtParticle structure to flat MCParticle list.
void	updateGraphParticle (EvtParticle *eParticle, MCParticleGraph::GraphParticle *gParticle, TVector3 pPrimaryVertex, double timeOffset=0)
	Copy parameters from EvtParticle to MCParticle.

Detailed Description

Class to interface EvtGen.

This class is responsible to handle all interaction with evtgen and its classes when generating events. It sets up the models, calls evtgen to generate the events and converts the evtgen particles to a list of MCParticles

Definition at line 34 of file EvtGenInterface.h.

Member Function Documentation

createEvtGen()

EvtGen * createEvtGen ( const std::string &  decayFileName, bool  coherentMixing  )

static

Create and initialize an EvtGen instance:

• Make sure Random engine is setup correctly
• Create evt.pdl on the fly from current contents of particle database
• Add photos/all models
• Use Coherent mixing unless set otherwise

Definition at line 49 of file EvtGenInterface.cc.

{
  IOIntercept::OutputToLogMessages initLogCapture("EvtGen", LogConfig::c_Debug, LogConfig::c_Debug, 100, 100);
  initLogCapture.start();
  EvtRandom::setRandomEngine(&EvtGenInterface::m_eng);
 
  // Official BelleII models
  std::list<EvtDecayBase*> extraModels = EvtGenModelRegister::getModels();
 
  // Fill model list with pythia, photos etc.
  // The parameter 'false' means that Pythia codes must not be converted,
  // since the conversion is applied to all the decfiles since release-06.
  EvtExternalGenList genList{false};
  EvtAbsRadCorr* radCorrEngine = genList.getPhotosModel();
  list<EvtDecayBase*> modelList = genList.getListOfModels();
  extraModels.insert(extraModels.end(), modelList.begin(), modelList.end());
 
  FileSystem::TemporaryFile tmp;
  EvtGenDatabasePDG::Instance()->WriteEvtGenTable(tmp);
 
  auto mixingMode = EvtCPUtil::Incoherent;
  if (coherentMixing)
    mixingMode =  EvtCPUtil::Coherent;
  else {
    B2WARNING("Evtgen has been set to decay the B mesons incoherently. This is useful as a workaround only to generate Y(5S, 6S) -> BBar for QCD studies.");
    B2WARNING("If you are generating Y(4S) events, you _really_ must use the coherent decay mode.");
  }
 
  return new EvtGen(DECFileName.c_str(), tmp.getName().c_str(), &EvtGenInterface::m_eng,
                    radCorrEngine, &extraModels,  mixingMode);
 
  initLogCapture.finish();
}

Member Data Documentation

m_parent

EvtParticle* m_parent

protected

Variable needed for parent particle.

Definition at line 79 of file EvtGenInterface.h.

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

• generators/evtgen/include/EvtGenInterface.h
• generators/evtgen/src/EvtGenInterface.cc