Interface to PYTHIA particle decayer.
The Pythia8Decayer2023 is a concrete implementation of the Decayer interface. More...

#include <Pythia8Decayer2023.h>

Inheritance diagram for genie::Pythia8Decayer2023:

[legend]

Collaboration diagram for genie::Pythia8Decayer2023:

[legend]

Public Member Functions
	Pythia8Decayer2023 ()
	Pythia8Decayer2023 (string config)
virtual	~Pythia8Decayer2023 ()
void	ProcessEventRecord (GHepRecord *event) const

Private Member Functions
void	Initialize (void) const
bool	IsHandled (int pdgc) const
void	InhibitDecay (int pdgc, TDecayChannel *ch=0) const
void	UnInhibitDecay (int pdgc, TDecayChannel *ch=0) const
bool	Decay (int ip, GHepRecord *event) const
double	SumOfBranchingRatios (int kc) const
int	FindPythiaDecayChannel (int kc, TDecayChannel *ch) const
bool	MatchDecayChannels (int ic, TDecayChannel *ch) const

Private Attributes
double	fWeight

Additional Inherited Members
Protected Member Functions inherited from genie::Decayer
	Decayer ()
	Decayer (string name)
	Decayer (string name, string config)
virtual void	LoadConfig (void)
virtual bool	ToBeDecayed (int pdgc, GHepStatus_t ist) const
virtual bool	IsUnstable (int pdgc) const
virtual	~Decayer ()
void	Configure (const Registry &config)
void	Configure (string config)
Protected Member Functions inherited from genie::EventRecordVisitorI
	EventRecordVisitorI ()
	EventRecordVisitorI (string name)
	EventRecordVisitorI (string name, string config)
virtual	~EventRecordVisitorI ()
Protected Member Functions inherited from genie::Algorithm
	Algorithm ()
	Algorithm (string name)
	Algorithm (string name, string config)
void	Initialize (void)
void	DeleteConfig (void)
void	DeleteSubstructure (void)
Registry *	ExtractLocalConfig (const Registry &in) const
Registry *	ExtractLowerConfig (const Registry &in, const string &alg_key) const
	Split an incoming configuration Registry into a block valid for the sub-algo identified by alg_key.
template<class T>
bool	GetParam (const RgKey &name, T &p, bool is_top_call=true) const
template<class T>
bool	GetParamDef (const RgKey &name, T &p, const T &def) const
template<class T>
int	GetParamVect (const std::string &comm_name, std::vector< T > &v, bool is_top_call=true) const
	Handle to load vectors of parameters.
int	GetParamVectKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
template<class T>
int	GetParamMat (const std::string &comm_name, TMatrixT< T > &mat, bool is_top_call=true) const
	Handle to load matrix of parameters.
template<class T>
int	GetParamMatSym (const std::string &comm_name, TMatrixTSym< T > &mat, bool is_top_call=true) const
int	GetParamMatKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
int	AddTopRegistry (Registry *rp, bool owns=true)
	add registry with top priority, also update ownership
int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership
int	MergeTopRegistry (const Registry &r)
int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships.
virtual	~Algorithm ()
virtual void	FindConfig (void)
virtual const Registry &	GetConfig (void) const
Registry *	GetOwnedConfig (void)
virtual const AlgId &	Id (void) const
	Get algorithm ID.
virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status.
virtual bool	AllowReconfig (void) const
virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm.
virtual void	SetId (const AlgId &id)
	Set algorithm ID.
virtual void	SetId (string name, string config)
const Algorithm *	SubAlg (const RgKey &registry_key) const
void	AdoptConfig (void)
void	AdoptSubstructure (void)
virtual void	Print (ostream &stream) const
	Print algorithm info.
Static Protected Member Functions inherited from genie::Algorithm
static string	BuildParamVectKey (const std::string &comm_name, unsigned int i)
static string	BuildParamVectSizeKey (const std::string &comm_name)
static string	BuildParamMatKey (const std::string &comm_name, unsigned int i, unsigned int j)
static string	BuildParamMatRowSizeKey (const std::string &comm_name)
static string	BuildParamMatColSizeKey (const std::string &comm_name)
Protected Attributes inherited from genie::Decayer
bool	fGenerateWeighted
	generate weighted or unweighted decays?
bool	fRunBefHadroTransp
	is invoked before or after FSI?
PDGCodeList	fParticlesToDecay
	list of particles to be decayed
PDGCodeList	fParticlesNotToDecay
	list of particles for which decay is inhibited
Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig
bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...)
AlgId	fID
	algorithm name and configuration set
vector< Registry * >	fConfVect
vector< bool >	fOwnerships
	ownership for every registry in fConfVect
AlgStatus_t	fStatus
	algorithm execution status
AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool)

Detailed Description

Interface to PYTHIA particle decayer.
The Pythia8Decayer2023 is a concrete implementation of the Decayer interface.

Author: Robert Hatcher <rhatcher \at fnal.gov> Fermilab

Created:\n December 21, 2023

License:\n Copyright (c) 2003-2025, The GENIE Collaboration: For the full text of the license visit http://copyright.genie-mc.org

Definition at line 32 of file Pythia8Decayer2023.h.

Constructor & Destructor Documentation

◆ Pythia8Decayer2023() [1/2]

Pythia8Decayer2023::Pythia8Decayer2023 ( )

Definition at line 37 of file Pythia8Decayer2023.cxx.

                                       :
Decayer("genie::Pythia8Decayer2023")
{
  this->Initialize();
}

References genie::Decayer::Decayer(), and Initialize().

◆ Pythia8Decayer2023() [2/2]

Pythia8Decayer2023::Pythia8Decayer2023 ( string config )

Definition at line 43 of file Pythia8Decayer2023.cxx.

                                                    :
Decayer("genie::Pythia8Decayer2023", config)
{
  this->Initialize();
}

References genie::Decayer::Decayer(), and Initialize().

◆ ~Pythia8Decayer2023()

Pythia8Decayer2023::~Pythia8Decayer2023 ( )

virtual

Definition at line 49 of file Pythia8Decayer2023.cxx.

{
 
}

Member Function Documentation

◆ Decay()

bool Pythia8Decayer2023::Decay	(	int	ip,
		GHepRecord *	event ) const

private

Definition at line 87 of file Pythia8Decayer2023.cxx.

{
  fWeight = 1.; // reset previous decay weight
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  // Get the one-and-only instance of Pythia8 that GENIE will use
  Pythia8::Pythia* gPythia = Pythia8Singleton::Instance()->Pythia8();
 
  // Get particle to be decayed
  GHepParticle * decay_particle = event->Particle(decay_particle_id);
  if(!decay_particle) return 0;
 
  // Check whether the interaction is off a nuclear target or free nucleon
  // Depending on whether this module is run before or after the hadron
  // transport module it would affect the daughters status code
  GHepParticle * target_nucleus = event->TargetNucleus();
  bool in_nucleus = (target_nucleus!=0);
 
  // Get the particle 4-momentum, 4-position and PDG code
  TLorentzVector decay_particle_p4 = *(decay_particle->P4());
  TLorentzVector decay_particle_x4 = *(decay_particle->X4());
  int decay_particle_pdg_code = decay_particle->Pdg();
 
  TVector3 polz;
  decay_particle->GetPolarization(polz);
 
  gPythia->event.reset();
 
  // check if pdgid is consistent with Pythia8 particle table
  //
  if ( !gPythia->particleData.findParticle(decay_particle_pdg_code) ) {
    LOG("Pythia8Decay", pWARN)
      << " can NOT find pdgid = " << decay_particle_pdg_code
      << " in Pythia8::ParticleData";
      return false;
    }
 
  if ( !gPythia->particleData.canDecay(decay_particle_pdg_code) ) {
    LOG("Pythia8Decay", pWARN)
      << " Particle of pdgid = " << decay_particle_pdg_code
      << " can NOT be decayed by Pythia8";
      return false;
  }
 
  // NOTE: Energy should be in GeV
 
  gPythia->event.append( decay_particle_pdg_code, 1, 0, 0,
                         decay_particle_p4.Px(),
                         decay_particle_p4.Py(),
                         decay_particle_p4.Pz(),
                         decay_particle_p4.E(),
                         decay_particle_p4.M() );
 
  // specify polarization, if any
 
  // NOTE: while in Py8 polarization is a double variable ,
  //       in reality it's expected to be -1, 0., or 1 in case of "external" tau's,
  //       similar to LHA SPINUP; see Particle Decays, Hadron and Tau Decays in docs at
  //       https://pythia.org/manuals/pythia8305/Welcome.html
  //       so it's not able to handle anything like 0.99, thus we're rounding off
  //  gPythia->event.back().pol( round( std::cos( track.GetPolarization().angle( track.GetMomentumDirection() ) ) ) );
  double a = decay_particle_p4.Vect().Angle(polz);
  gPythia->event.back().pol( round( std::cos(a) ) );
 
  int npart_before_decay = gPythia->event.size();
 
  gPythia->next();
 
  //gPythia->event.list();
  //gPythia->stat();
 
  int npart_after_decay = gPythia->event.size();
 
  LOG("Pythia8Decay", pINFO) << "before " << npart_before_decay << " after " << npart_after_decay;
 
  // the values of space coordinates from pythia are in mm.
  // our conventions want it in fm
  constexpr double space_scale = units::mm / units::fm ;
 
  //  the values of time coordinate from pythia is in mm/c.
  // our conventions want it in ys
  constexpr double time_scale = 1e21 * units::m / units::s ;
 
 
  // create & fill up decay products
  //
  for ( int ip=npart_before_decay; ip<npart_after_decay; ++ip )
    {
 
      // only select final state decay products (direct or via subsequent decays);
      // skip all others
      //
      // NOTE: in general, final state decays products will have
      //       positive status code between 91 and 99
      //       (in case such information could be of interest in the future)
      //
      if ( gPythia->event[ip].status() < 0 ) continue;
 
      Pythia8::Event &fEvent = gPythia->event;
 
      int daughter_pdg_code   = fEvent[ip].id();
 
      int mother1 = decay_particle_id;
      int mother2 = -1;
 
      int daughter1 = -1;
      int daughter2 = -1;
 
      bool is_hadron = pdg::IsHadron(daughter_pdg_code);
      bool hadron_in_nuc = (in_nucleus && is_hadron && fRunBefHadroTransp);
 
      GHepStatus_t daughter_status_code = (hadron_in_nuc) ?
        kIStHadronInTheNucleus : kIStStableFinalState;
 
      GHepParticle mcp = GHepParticle(
                                      daughter_pdg_code, // pdg
                                      daughter_status_code, // status
                                      mother1,           // first parent
                                      mother2,           // second parent
                                      daughter1,         // first daughter
                                      daughter2,         // second daughter
                                      fEvent[ip].px(),   // px
                                      fEvent[ip].py(),   // py
                                      fEvent[ip].pz(),   // pz
                                      fEvent[ip].e(),    // e
                                      fEvent[ip].xProd() * space_scale + decay_particle_x4.X(), // x
                                      fEvent[ip].yProd() * space_scale + decay_particle_x4.Y(), // y
                                      fEvent[ip].zProd() * space_scale + decay_particle_x4.Z(), // z
                                      fEvent[ip].tProd() * time_scale  + decay_particle_x4.T()  // t
                                      );
 
    SLOG("Pythia8Decay", pINFO)
       << "Adding daughter particle with PDG code = "
       << daughter_pdg_code << ", m = " << mcp.Mass()
       << " GeV, E = " << mcp.Energy() << " GeV)";
 
    event->AddParticle(mcp);
 
    }
 
  // Update the event weight for each weighted particle decay
  double weight = event->Weight() * fWeight;
  event->SetWeight(weight);
 
  // Mark input particle as a 'decayed state' & add its daughter links
  decay_particle->SetStatus(kIStDecayedState);
 
  return true;
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
 
  return false;
#endif
 
}

References a, e, genie::GHepParticle::Energy(), genie::units::fm, genie::Decayer::fRunBefHadroTransp, fWeight, genie::gAbortingInErr, genie::GHepParticle::GetPolarization(), genie::Pythia8Singleton::Instance(), genie::pdg::IsHadron(), genie::kIStDecayedState, genie::kIStHadronInTheNucleus, genie::kIStStableFinalState, LOG, genie::units::m, genie::GHepParticle::Mass(), genie::units::mm, genie::GHepParticle::P4(), genie::GHepParticle::Pdg(), pFATAL, pINFO, pWARN, genie::units::s, genie::GHepParticle::SetStatus(), SLOG, and genie::GHepParticle::X4().

Referenced by ProcessEventRecord().

◆ FindPythiaDecayChannel()

int Pythia8Decayer2023::FindPythiaDecayChannel	(	int	kc,
		TDecayChannel *	ch ) const

private

Definition at line 461 of file Pythia8Decayer2023.cxx.

{
  if(!dc) return -1;
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  LOG("Pythia8Decay", pFATAL)
    << "Pythia8Decayer2023::FindPythiaDecayChannel() not yet implemented";
  gAbortingInErr = true;
  std::exit(1);
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
 
  return -1;
}

References genie::gAbortingInErr, LOG, and pFATAL.

◆ InhibitDecay()

void Pythia8Decayer2023::InhibitDecay	(	int	pdgc,
		TDecayChannel *	ch = 0 ) const

privatevirtual

Implements genie::Decayer.

Definition at line 295 of file Pythia8Decayer2023.cxx.

{
  if(! this->IsHandled(pdg_code)) return;
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  Pythia8::Pythia* gPythia = Pythia8Singleton::Instance()->Pythia8();
  bool known = gPythia->particleData.isParticle(pdg_code);
  if ( ! known ) {
    LOG("Pythia8Decay", pERROR)
      << "Can not switch off decays of " << pdg_code
      << " as it is UNKNOWN to Pythia8";
    return;
  }
 
  auto pdentry = gPythia->particleData.particleDataEntryPtr(pdg_code);
 
  int ifirst_chan = 0;
  int ilast_chan  = pdentry->sizeChannels() - 1;
  if (ilast_chan < 0) {
    LOG("Pythia8Decay", pDEBUG)
      << "No available decay channels for " << pdg_code;
    return;
  }
 
  if(dc) {
    LOG("Pythia8Decay", pFATAL)
       << "Switching off individual decay channels for particle = " << pdg_code
       << " is NOT yet supported for Pythia8";
    exit(42);
    return;
  }
 
  //std::cout << "Before inhibiting channels " << ifirst_chan << "," << ilast_chan
  //          << " of " << pdg_code << std::endl;
  //gPythia->particleData.list(pdg_code);
 
  for (int ichan=ifirst_chan; ichan<=ilast_chan; ++ichan) {
    int onMode = pdentry->channel(ichan).onMode();
    // 4 possible modes:  0=off particle & antiparticle; 1=on both; 2=on particle only; 3=on antiparticle only
    bool is_particle = (pdg_code>0);
    // we're trying to turn off the mode
    switch ( onMode ) {
    case 0: // off for particles & antiparticles
      break; // already off
    case 1: // on for both particle & antiparticle
      onMode = (is_particle ? 3 : 2);
      break;
    case 2: // on for particle only
      onMode = (is_particle ? 0 : 2);
      break;
    case 3: // on for antiparticle only
      onMode = (is_particle ? 3 : 0);
      break;
    }
    pdentry->channel(ichan).onMode(onMode);
  }
 
  //std::cout << "After inhibiting channels " << ifirst_chan << "," << ilast_chan
  //          << " of " << pdg_code << std::endl;
  //gPythia->particleData.list(pdg_code);
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
 
}

References genie::gAbortingInErr, genie::Pythia8Singleton::Instance(), IsHandled(), LOG, pDEBUG, pERROR, and pFATAL.

◆ Initialize()

void Pythia8Decayer2023::Initialize ( void ) const

private

Definition at line 247 of file Pythia8Decayer2023.cxx.

{
#ifdef __GENIE_PYTHIA8_ENABLED__
  fWeight = 1.;
 
  Pythia8::Pythia* gPythia = Pythia8Singleton::Instance()->Pythia8();
  gPythia->readString("ProcessLevel:all = off");
  gPythia->readString("ProcessLevel:resonanceDecays=on");
 
  gPythia->readString("Print:quiet = on");
 
  // sync GENIE and PYTHIA8 seeds
  RandomGen * rnd = RandomGen::Instance();
  long int seed = rnd->GetSeed();
  gPythia->readString("Random::setSeed = on");
  gPythia->settings.mode("Random:seed",seed);
  LOG("Pythia8Decay", pINFO)
    << "PYTHIA8 seed = " << gPythia->settings.mode("Random:seed");
 
  gPythia->init();
 
  // shut off decays of pi0's as we want Geant4 to handle them
  // if other immediate decay products should be handled by Geant4,
  // their respective decay modes should be shut off as well
  //
  gPythia->readString("111:onMode = off");
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
}

References fWeight, genie::gAbortingInErr, genie::RandomGen::GetSeed(), genie::Pythia8Singleton::Instance(), genie::RandomGen::Instance(), LOG, pFATAL, and pINFO.

Referenced by Pythia8Decayer2023(), and Pythia8Decayer2023().

◆ IsHandled()

bool Pythia8Decayer2023::IsHandled ( int pdgc ) const

privatevirtual

Implements genie::Decayer.

Definition at line 282 of file Pythia8Decayer2023.cxx.

{
// does not handle requests to decay baryon resonances
 
 bool is_handled = (!utils::res::IsBaryonResonance(pdg_code));
 
 LOG("Pythia8Decay", pDEBUG)
    << "Can decay particle with PDG code = " << pdg_code
    << "? " << ((is_handled)? "Yes" : "No");
 
  return is_handled;
}

References genie::utils::res::IsBaryonResonance(), LOG, and pDEBUG.

Referenced by InhibitDecay(), ProcessEventRecord(), and UnInhibitDecay().

◆ MatchDecayChannels()

bool Pythia8Decayer2023::MatchDecayChannels	(	int	ic,
		TDecayChannel *	ch ) const

private

Definition at line 482 of file Pythia8Decayer2023.cxx.

{
  // num. of daughters in the input TDecayChannel & the input PYTHIA ichannel
  //int nd = dc->NDaughters();
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  LOG("Pythia8Decay", pFATAL)
    << "Pythia8Decayer2023::MatchDecayChannels() not yet implemented";
  gAbortingInErr = true;
  std::exit(1);
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
 
  return true;
}

References genie::gAbortingInErr, LOG, and pFATAL.

◆ ProcessEventRecord()

void Pythia8Decayer2023::ProcessEventRecord ( GHepRecord * event ) const

virtual

Implements genie::EventRecordVisitorI.

Definition at line 54 of file Pythia8Decayer2023.cxx.

{
  LOG("ResonanceDecay", pINFO)
    << "Running PYTHIA8 particle decayer "
    << ((fRunBefHadroTransp) ? "*before*" : "*after*") << " FSI";
 
  // Loop over particles, find unstable ones and decay them
  TObjArrayIter piter(event);
  GHepParticle * p = 0;
  int ipos = -1;
 
  while( (p = (GHepParticle *) piter.Next()) ) {
    ipos++;
 
    LOG("Pythia8Decay", pDEBUG) << "Checking: " << p->Name();
 
    int pdg_code = p->Pdg();
    GHepStatus_t status_code = p->Status();
 
    if(!this->IsHandled  (pdg_code)) continue;
    if(!this->ToBeDecayed(pdg_code, status_code)) continue;
 
    LOG("Pythia8Decay", pNOTICE)
          << "Decaying unstable particle: " << p->Name();
 
    bool decayed = this->Decay(ipos, event);
    assert(decayed); // handle this more graciously and throw an exception
  }
 
  LOG("Pythia8Decay", pNOTICE)
     << "Done finding & decaying unstable particles";
}

References Decay(), genie::Decayer::fRunBefHadroTransp, IsHandled(), LOG, genie::GHepParticle::Name(), pDEBUG, genie::GHepParticle::Pdg(), pINFO, pNOTICE, genie::GHepParticle::Status(), and genie::Decayer::ToBeDecayed().

◆ SumOfBranchingRatios()

double Pythia8Decayer2023::SumOfBranchingRatios ( int kc ) const

private

Definition at line 436 of file Pythia8Decayer2023.cxx.

{
// Sum of branching ratios for enabled channels
//
  double sumbr=0.;
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  LOG("Pythia8Decay", pFATAL)
    << "Pythia8Decayer2023::SumOfBranchingRatios() not yet implemented";
  gAbortingInErr = true;
  std::exit(1);
 
  LOG("Pythia8Decay", pINFO) << "Sum{BR} = " << sumbr;
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
 
  return sumbr;
}

References genie::gAbortingInErr, LOG, pFATAL, and pINFO.

◆ UnInhibitDecay()

void Pythia8Decayer2023::UnInhibitDecay	(	int	pdgc,
		TDecayChannel *	ch = 0 ) const

privatevirtual

Implements genie::Decayer.

Definition at line 366 of file Pythia8Decayer2023.cxx.

{
  if(! this->IsHandled(pdg_code)) return;
 
#ifdef __GENIE_PYTHIA8_ENABLED__
 
  Pythia8::Pythia* gPythia = Pythia8Singleton::Instance()->Pythia8();
  bool known = gPythia->particleData.isParticle(pdg_code);
  if ( ! known ) {
    LOG("Pythia8Decay", pERROR)
      << "Can not switch on decays of " << pdg_code
      << " as it is UNKNOWN to Pythia8";
    return;
  }
 
  auto pdentry = gPythia->particleData.particleDataEntryPtr(pdg_code);
 
  int ifirst_chan = 0;
  int ilast_chan  = pdentry->sizeChannels() - 1;
  if (ilast_chan < 0) {
    LOG("Pythia8Decay", pDEBUG)
      << "No available decay channels for " << pdg_code;
    return;
  }
 
  if(dc) {
    LOG("Pythia8Decay", pFATAL)
       << "Switching on individual decay channels for particle = " << pdg_code
       << " is NOT yet supported for Pythia8";
    exit(42);
    return;
  }
 
  //std::cout << "Before uninhibiting channels " << ifirst_chan << "," << ilast_chan
  //          << " of " << pdg_code << std::endl;
  //gPythia->particleData.list(pdg_code);
 
  for (int ichan=ifirst_chan; ichan<=ilast_chan; ++ichan) {
    int onMode = pdentry->channel(ichan).onMode();
    // 4 possible modes:  0=off particle & antiparticle; 1=on both; 2=on particle only; 3=on antiparticle only
    bool is_particle = (pdg_code>0);
    // we're trying to turn off the mode
    switch ( onMode ) {
    case 0: // off for particles & antiparticles
      onMode = (is_particle ? 2 : 3);
      break;
    case 1: // on for both particle & antiparticle
      break; // already on
    case 2: // on for particle only
      onMode = (is_particle ? 2 : 0);
      break;
    case 3: // on for antiparticle only
      onMode = (is_particle ? 0 : 3);
      break;
    }
    pdentry->channel(ichan).onMode(onMode);
  }
 
  //std::cout << "After uninhibiting channels " << ifirst_chan << "," << ilast_chan
  //          << " of " << pdg_code << std::endl;
  //gPythia->particleData.list(pdg_code);
 
#else
  LOG("Pythia8Decay", pFATAL)
    << "calling GENIE/PYTHIA8 decay without enabling PYTHIA8";
  gAbortingInErr = true;
  std::exit(1);
#endif
}

References genie::gAbortingInErr, genie::Pythia8Singleton::Instance(), IsHandled(), LOG, pDEBUG, pERROR, and pFATAL.

Member Data Documentation

◆ fWeight

double genie::Pythia8Decayer2023::fWeight

mutableprivate

Definition at line 53 of file Pythia8Decayer2023.h.

Referenced by Decay(), and Initialize().

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

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Pythia8Decayer2023() [1/2]

◆ Pythia8Decayer2023() [2/2]

◆ ~Pythia8Decayer2023()

Member Function Documentation

◆ Decay()

◆ FindPythiaDecayChannel()

◆ InhibitDecay()

◆ Initialize()

◆ IsHandled()

◆ MatchDecayChannels()

◆ ProcessEventRecord()

◆ SumOfBranchingRatios()

◆ UnInhibitDecay()

Member Data Documentation

◆ fWeight