genie::SKHadronicSystemGenerator Class Reference

Generates the f/s hadronic system in single-Kaon production interactions. Is a concrete implementation of the EventRecordVisitorI interface. More...

#include <SKHadronicSystemGenerator.h>

Inheritance diagram for genie::SKHadronicSystemGenerator:

Collaboration diagram for genie::SKHadronicSystemGenerator:

Public Member Functions
	SKHadronicSystemGenerator ()
	SKHadronicSystemGenerator (string config)
	~SKHadronicSystemGenerator ()
void	ProcessEventRecord (GHepRecord *event_rec) const
void	CalculateHadronicSystem_AtharSingleKaon (GHepRecord *event_rec) const
Public Member Functions inherited from genie::HadronicSystemGenerator
void	AddTargetNucleusRemnant (GHepRecord *event_rec) const
void	AddFinalHadronicSyst (GHepRecord *event_rec) const
void	PreHadronTransportDecays (GHepRecord *event_rec) const
TLorentzVector	Hadronic4pLAB (GHepRecord *event_rec) const
TLorentzVector	MomentumTransferLAB (GHepRecord *event_rec) const
TVector3	HCM2LAB (GHepRecord *event_rec) const
int	HadronShowerCharge (GHepRecord *event_rec) const
int	ResonanceCharge (GHepRecord *event_rec) const
Public Member Functions inherited from genie::EventRecordVisitorI
virtual	~EventRecordVisitorI ()
Public Member Functions inherited from genie::Algorithm
virtual	~Algorithm ()
virtual void	Configure (const Registry &config)
virtual void	Configure (string config)
virtual void	FindConfig (void)
virtual const Registry &	GetConfig (void) const
Registry *	GetOwnedConfig (void)
virtual const AlgId &	Id (void) const
	Get algorithm ID. More...
virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status. More...
virtual bool	AllowReconfig (void) const
virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm. More...
virtual void	SetId (const AlgId &id)
	Set algorithm ID. More...
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. More...

Additional Inherited Members
Static Public 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 Member Functions inherited from genie::HadronicSystemGenerator
	HadronicSystemGenerator ()
	HadronicSystemGenerator (string name)
	HadronicSystemGenerator (string name, string config)
	~HadronicSystemGenerator ()
Protected Member Functions inherited from genie::EventRecordVisitorI
	EventRecordVisitorI ()
	EventRecordVisitorI (string name)
	EventRecordVisitorI (string name, string config)
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. More...
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. More...
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. More...
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 More...
int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership More...
int	MergeTopRegistry (const Registry &r)
int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships. More...
Protected Attributes inherited from genie::HadronicSystemGenerator
const EventRecordVisitorI *	fPreINukeDecayer
Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig
bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...) More...
AlgId	fID
	algorithm name and configuration set More...
vector< Registry * >	fConfVect
vector< bool >	fOwnerships
	ownership for every registry in fConfVect More...
AlgStatus_t	fStatus
	algorithm execution status More...
AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool) More...

Detailed Description

Generates the f/s hadronic system in single-Kaon production interactions. Is a concrete implementation of the EventRecordVisitorI interface.

Author

Costas Andreopoulos <c.andreopoulos cern.ch> University of Liverpool

Created:

March 20, 2014

License:

Copyright (c) 2003-2024, The GENIE Collaboration For the full text of the license visit http://copyright.genie-mc.org

Definition at line 26 of file SKHadronicSystemGenerator.h.

Constructor & Destructor Documentation

SKHadronicSystemGenerator::SKHadronicSystemGenerator

(

)

Definition at line 39 of file SKHadronicSystemGenerator.cxx.

                                                     :
HadronicSystemGenerator("genie::SKHadronicSystemGenerator")
{

}

SKHadronicSystemGenerator::SKHadronicSystemGenerator

(

string

config

)

Definition at line 45 of file SKHadronicSystemGenerator.cxx.

                                                                  :
HadronicSystemGenerator("genie::SKHadronicSystemGenerator", config)
{

}

SKHadronicSystemGenerator::~SKHadronicSystemGenerator

(

)

Definition at line 51 of file SKHadronicSystemGenerator.cxx.

{

}

Member Function Documentation

void SKHadronicSystemGenerator::CalculateHadronicSystem_AtharSingleKaon

(

GHepRecord *

event_rec

)

const

Definition at line 65 of file SKHadronicSystemGenerator.cxx.

References genie::GHepRecord::AddParticle(), genie::GHepRecord::EventFlags(), genie::Interaction::ExclTag(), genie::GHepRecord::FinalStatePrimaryLepton(), genie::PDGLibrary::Find(), genie::Kinematics::GetKV(), genie::GHepRecord::HitNucleon(), genie::GHepRecord::HitNucleonPosition(), genie::Target::HitNucP4(), genie::Interaction::InitState(), genie::PDGLibrary::Instance(), genie::Target::IsNucleus(), genie::Interaction::KinePtr(), genie::kIStHadronInTheNucleus, genie::kIStStableFinalState, genie::kKineGenErr, genie::kKVSelphikq, genie::kKVSelTk, genie::constants::kNeutronMass, genie::kPdgNeutron, genie::kPdgProton, genie::constants::kProtonMass, LOG, genie::XclsTag::NProtons(), genie::GHepParticle::P4(), pDEBUG, genie::GHepRecord::Probe(), pWARN, genie::exceptions::EVGThreadException::SetReason(), genie::exceptions::EVGThreadException::SetReturnStep(), genie::XclsTag::StrangeHadronPdg(), genie::GHepRecord::Summary(), genie::exceptions::EVGThreadException::SwitchOnStepBack(), genie::InitialState::Tgt(), and genie::GHepParticle::X4().

Referenced by ProcessEventRecord().

{
//
// This method generates the final state hadronic system (kaon + nucleus)
//

  Interaction * interaction = evrec->Summary();
  Kinematics * kinematics = interaction->KinePtr();
  const XclsTag & xcls_tag  = interaction->ExclTag();

  //-- Access neutrino, initial nucleus and final state prim. lepton entries
  GHepParticle * nu  = evrec->Probe();
  GHepParticle * Ni  = evrec->HitNucleon();
  GHepParticle * fsl = evrec->FinalStatePrimaryLepton();
  assert(nu);
  assert(Ni);
  assert(fsl);

  const TLorentzVector vtx   = *(nu->X4());
  const TLorentzVector p4nu_lab  = *(nu ->P4());
  const TLorentzVector p4fsl_lab = *(fsl->P4());

  // these will get boosted to the nucleon rest frame
  TLorentzVector p4nu = p4nu_lab;
  TLorentzVector p4fsl = p4fsl_lab;

  // Transform the neutrino and final-state lepton to the struck nucleon rest frame
  const TLorentzVector pnuc4 = interaction->InitState().Tgt().HitNucP4(); // 4-momentum of struck nucleon in lab frame
  TVector3 beta = pnuc4.BoostVector();
  p4nu.Boost(-1.*beta);
  p4fsl.Boost(-1.*beta);

  LOG( "SKHadron", pDEBUG ) << "\nStruck nucleon p = (" << pnuc4.X() << ", " << pnuc4.Y() << ", " << pnuc4.Z() << ")";
  LOG( "SKHadron", pDEBUG ) << "\nLab frame neutrino E = " << p4nu_lab.E() << " lepton " << p4fsl_lab.E() << " rest frame " << p4nu.E() << " lepton " << p4fsl.E();

  //-- Determine the pdg code of the final state nucleon
  int nuc_pdgc = (xcls_tag.NProtons()) ? kPdgProton : kPdgNeutron; // there's only ever one nucleon
  int kaon_pdgc = xcls_tag.StrangeHadronPdg();

  const Target & tgt = interaction->InitState().Tgt();
  GHepStatus_t ist = (tgt.IsNucleus()) ?
                          kIStHadronInTheNucleus : kIStStableFinalState;

  //-- basic kinematic inputs
  double Mf    = (xcls_tag.NProtons()) ? kProtonMass : kNeutronMass; // there's only ever one nucleon
  double M     = pnuc4.M();  // Mass of the struck nucleon
  double mk    = PDGLibrary::Instance()->Find(kaon_pdgc)->Mass(); // K+ and K0 mass are slightly different
  double mk2   = TMath::Power(mk,2);

  //-- specific kinematic quantities
  double kaon_T = kinematics->GetKV(kKVSelTk);
  double kaon_E = kaon_T + mk;
  double pk = sqrt( kaon_E*kaon_E - mk2 );

  TLorentzVector q = p4nu - p4fsl; // nucleon rest frame

  TVector3 qvec = q.Vect(); // nucleon rest frame
  double q3 = qvec.Mag(); // in q frame (0,0,q3)

  // Equation 17 of notes from M. Rafi Alam dated 6 November 2013
  double eN = q.E() + M - kaon_E; // FS nucleon total energy
  double cos_thetaKq = (q3*q3 + pk*pk + Mf*Mf - eN*eN)/(2*q3*pk);

  LOG( "SKHadron", pDEBUG ) <<
    "Cosine theta_kq = " << cos_thetaKq << "\n" <<
    "q.E = " << q.E() << " M = " << M << " kaon E " << kaon_E << " q3 = " << q3 << " pk = " << pk;

  if(cos_thetaKq > 1.0) {
     LOG("SKHadron", pWARN) << "Invalid selected kinematics; Attempt regenerating";
     evrec->EventFlags()->SetBitNumber(kKineGenErr, true);
     genie::exceptions::EVGThreadException exception;
     exception.SetReason("Invalid selected kinematics");
     exception.SwitchOnStepBack();
     exception.SetReturnStep(0);
     throw exception;
  }

//  this can be slightly larger than 1 due to numerical precision issues -- don't let it be
//  if( cos_thetaKq > 1.0 ) {
//    LOG( "SKHadron", pWARN ) <<
//      "Cosine theta_kq = " << cos_thetaKq << ", setting to 1.0\n" <<
//      "q.E = " << q.E() << " M = " << M << " kaon E " << kaon_E << " q3 = " << q3 << " pk = " << pk;
//    cos_thetaKq = 1.0;
//  }


  // Get phi for the k-q plane relative to nu-l plane
  double phi_kq = kinematics->GetKV(kKVSelphikq);

  TVector3 kaon;
  kaon.SetMagThetaPhi( pk, TMath::ACos(cos_thetaKq), phi_kq );

  TVector3 nucleon( -kaon.X(), -kaon.Y(), q3 - kaon.Z() ); // force 3-momentum conservation in q frame

  // Transform hadron momenta from z axis along q to lab frame
  kaon.RotateUz(qvec.Unit());
  nucleon.RotateUz(qvec.Unit());

  LOG( "SKHadron", pDEBUG ) <<
    "\nKaon (x,y,z) in nuc rest frame: (" << kaon.X() << ", " << kaon.Y() << ", " << kaon.Z() << ")" <<
    "\nNucleon:                        (" << nucleon.X() << ", " << nucleon.Y() << ", " << nucleon.Z() << ")";

  // make 4-vectors for the kaon and nucleon
  TLorentzVector p4kaon( kaon, sqrt(kaon.Mag2()+mk2) );
  TLorentzVector p4fsnuc( nucleon, sqrt(nucleon.Mag2()+Mf*Mf) );
  // these are in the struck nucleon rest frame...boost them to the lab frame
  p4kaon.Boost( beta );
  p4fsnuc.Boost( beta );

  LOG( "SKHadron", pDEBUG ) <<
    "\nKaon (x,y,z) in lab frame: (" << p4kaon.X() << ", " << p4kaon.Y() << ", " << p4kaon.Z() << ")" <<
    "\nNucleon:                   (" << p4fsnuc.X() << ", " << p4fsnuc.Y() << ", " << p4fsnuc.Z() << ")";

  double pxNf = p4fsnuc.Px();
  double pyNf = p4fsnuc.Py();
  double pzNf = p4fsnuc.Pz();
  double ENf = p4fsnuc.E();

  double pxKf = p4kaon.Px();
  double pyKf = p4kaon.Py();
  double pzKf = p4kaon.Pz();
  double EKf = p4kaon.E();

  //-- Save the particles at the GHEP record

  // mom is mother, not momentum
  int mom = evrec->HitNucleonPosition();

  // AddParticle (int pdg, GHepStatus_t ist, int mom1, int mom2, int dau1, int dau2, double px, double py, double pz, double E, double x, double y, double z, double t)

  evrec->AddParticle(
     nuc_pdgc, ist, mom,-1,-1,-1,
     pxNf, pyNf, pzNf, ENf, vtx.X(), vtx.Y(), vtx.Z(), vtx.T());

  evrec->AddParticle(
     kaon_pdgc,ist, mom,-1,-1,-1,
     pxKf, pyKf, pzKf, EKf, vtx.X(), vtx.Y(), vtx.Z(), vtx.T());

}

void SKHadronicSystemGenerator::ProcessEventRecord ( GHepRecord *  event_rec ) const

virtual

Implements genie::EventRecordVisitorI.

Definition at line 56 of file SKHadronicSystemGenerator.cxx.

References CalculateHadronicSystem_AtharSingleKaon().

{
// Access cross section algorithm for running thread
  //RunningThreadInfo * rtinfo = RunningThreadInfo::Instance();
  //const EventGeneratorI * evg = rtinfo->RunningThread();
  //const XSecAlgorithmI *fXSecModel = evg->CrossSectionAlg();
  CalculateHadronicSystem_AtharSingleKaon(evrec);
}

---

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

• SKHadronicSystemGenerator.h
• SKHadronicSystemGenerator.cxx