Gabriele Cosmo
632 lines
18 KiB
C++
632 lines
18 KiB
C++
//
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// ********************************************************************
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// * License and Disclaimer *
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// * *
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// * The Geant4 software is copyright of the Copyright Holders of *
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// * the Geant4 Collaboration. It is provided under the terms and *
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// * conditions of the Geant4 Software License, included in the file *
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// * LICENSE and available at http://cern.ch/geant4/license . These *
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// * include a list of copyright holders. *
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// * *
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// * Neither the authors of this software system, nor their employing *
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// * institutes,nor the agencies providing financial support for this *
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// * work make any representation or warranty, express or implied, *
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// * regarding this software system or assume any liability for its *
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// * use. Please see the license in the file LICENSE and URL above *
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// * for the full disclaimer and the limitation of liability. *
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// * *
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// * This code implementation is the result of the scientific and *
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// * technical work of the GEANT4 collaboration. *
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// * By using, copying, modifying or distributing the software (or *
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// * any work based on the software) you agree to acknowledge its *
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// * use in resulting scientific publications, and indicate your *
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// * acceptance of all terms of the Geant4 Software license. *
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// ********************************************************************
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//
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// $Id: G4NuMuNucleusNcModel.cc 91806 2015-08-06 12:20:45Z gcosmo $
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//
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// Geant4 Header : G4NuMuNucleusNcModel
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//
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// Author : V.Grichine 12.2.19
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//
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#include "G4NuMuNucleusNcModel.hh"
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#include "G4NeutrinoNucleusModel.hh"
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// #include "G4NuMuResQX.hh"
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#include "G4SystemOfUnits.hh"
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#include "G4ParticleTable.hh"
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#include "G4ParticleDefinition.hh"
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#include "G4IonTable.hh"
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#include "Randomize.hh"
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#include "G4RandomDirection.hh"
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// #include "G4Integrator.hh"
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#include "G4DataVector.hh"
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#include "G4PhysicsTable.hh"
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#include "G4KineticTrack.hh"
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#include "G4DecayKineticTracks.hh"
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#include "G4KineticTrackVector.hh"
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#include "G4Fragment.hh"
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#include "G4ReactionProductVector.hh"
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#include "G4NeutrinoMu.hh"
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#include "G4AntiNeutrinoMu.hh"
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#include "G4Nucleus.hh"
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#include "G4LorentzVector.hh"
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using namespace std;
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using namespace CLHEP;
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#ifdef G4MULTITHREADED
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G4Mutex G4NuMuNucleusNcModel::numuNucleusModel = G4MUTEX_INITIALIZER;
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#endif
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G4NuMuNucleusNcModel::G4NuMuNucleusNcModel(const G4String& name)
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: G4NeutrinoNucleusModel(name)
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{
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SetMinEnergy( 0.0*GeV );
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SetMaxEnergy( 100.*TeV );
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SetMinEnergy(1.e-6*eV);
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theNuMu = G4NeutrinoMu::NeutrinoMu();
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theANuMu = G4AntiNeutrinoMu::AntiNeutrinoMu();
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fMnumu = 0.;
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fData = fMaster = false;
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InitialiseModel();
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}
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G4NuMuNucleusNcModel::~G4NuMuNucleusNcModel()
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{}
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void G4NuMuNucleusNcModel::ModelDescription(std::ostream& outFile) const
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{
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outFile << "G4NuMuNucleusNcModel is a neutrino-nucleus (neutral current) scattering\n"
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<< "model which uses the standard model \n"
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<< "transfer parameterization. The model is fully relativistic\n";
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}
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/////////////////////////////////////////////////////////
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//
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// Read data from G4PARTICLEXSDATA (locally PARTICLEXSDATA)
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void G4NuMuNucleusNcModel::InitialiseModel()
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{
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G4String pName = "nu_mu";
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G4int nSize(0), i(0), j(0), k(0);
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if(!fData)
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{
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#ifdef G4MULTITHREADED
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G4MUTEXLOCK(&numuNucleusModel);
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if(!fData)
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{
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#endif
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fMaster = true;
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#ifdef G4MULTITHREADED
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}
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G4MUTEXUNLOCK(&numuNucleusModel);
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#endif
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}
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if(fMaster)
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{
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const char* path = G4FindDataDir("G4PARTICLEXSDATA");
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std::ostringstream ost1, ost2, ost3, ost4;
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ost1 << path << "/" << "neutrino" << "/" << pName << "/xarraynckr";
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std::ifstream filein1( ost1.str().c_str() );
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// filein.open("$PARTICLEXSDATA/");
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filein1>>nSize;
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for( k = 0; k < fNbin; ++k )
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{
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for( i = 0; i <= fNbin; ++i )
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{
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filein1 >> fNuMuXarrayKR[k][i];
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// G4cout<< fNuMuXarrayKR[k][i] << " ";
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}
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}
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// G4cout<<G4endl<<G4endl;
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ost2 << path << "/" << "neutrino" << "/" << pName << "/xdistrnckr";
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std::ifstream filein2( ost2.str().c_str() );
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filein2>>nSize;
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for( k = 0; k < fNbin; ++k )
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{
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for( i = 0; i < fNbin; ++i )
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{
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filein2 >> fNuMuXdistrKR[k][i];
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// G4cout<< fNuMuXdistrKR[k][i] << " ";
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}
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}
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// G4cout<<G4endl<<G4endl;
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ost3 << path << "/" << "neutrino" << "/" << pName << "/q2arraynckr";
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std::ifstream filein3( ost3.str().c_str() );
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filein3>>nSize;
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for( k = 0; k < fNbin; ++k )
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{
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for( i = 0; i <= fNbin; ++i )
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{
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for( j = 0; j <= fNbin; ++j )
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{
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filein3 >> fNuMuQarrayKR[k][i][j];
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// G4cout<< fNuMuQarrayKR[k][i][j] << " ";
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}
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}
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}
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// G4cout<<G4endl<<G4endl;
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ost4 << path << "/" << "neutrino" << "/" << pName << "/q2distrnckr";
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std::ifstream filein4( ost4.str().c_str() );
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filein4>>nSize;
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for( k = 0; k < fNbin; ++k )
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{
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for( i = 0; i <= fNbin; ++i )
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{
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for( j = 0; j < fNbin; ++j )
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{
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filein4 >> fNuMuQdistrKR[k][i][j];
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// G4cout<< fNuMuQdistrKR[k][i][j] << " ";
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}
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}
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}
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fData = true;
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}
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}
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/////////////////////////////////////////////////////////
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G4bool G4NuMuNucleusNcModel::IsApplicable(const G4HadProjectile & aPart,
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G4Nucleus & )
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{
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G4bool result = false;
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G4String pName = aPart.GetDefinition()->GetParticleName();
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G4double energy = aPart.GetTotalEnergy();
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if( pName == "nu_mu" // || pName == "anti_nu_mu" )
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&&
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energy > fMinNuEnergy )
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{
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result = true;
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}
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return result;
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}
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/////////////////////////////////////////// ClusterDecay ////////////////////////////////////////////////////////////
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//
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//
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G4HadFinalState* G4NuMuNucleusNcModel::ApplyYourself(
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const G4HadProjectile& aTrack, G4Nucleus& targetNucleus)
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{
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theParticleChange.Clear();
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fProton = f2p2h = fBreak = false;
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const G4HadProjectile* aParticle = &aTrack;
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G4double energy = aParticle->GetTotalEnergy();
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G4String pName = aParticle->GetDefinition()->GetParticleName();
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if( energy < fMinNuEnergy )
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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SampleLVkr( aTrack, targetNucleus);
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if( fBreak == true || fEmu < fMnumu ) // ~5*10^-6
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{
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// G4cout<<"ni, ";
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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// LVs of initial state
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G4LorentzVector lvp1 = aParticle->Get4Momentum();
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G4LorentzVector lvt1( 0., 0., 0., fM1 );
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G4double mPip = G4ParticleTable::GetParticleTable()->FindParticle(211)->GetPDGMass();
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// 1-pi by fQtransfer && nu-energy
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G4LorentzVector lvpip1( 0., 0., 0., mPip );
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G4LorentzVector lvsum, lv2, lvX;
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G4ThreeVector eP;
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G4double cost(1.), sint(0.), phi(0.), muMom(0.), massX2(0.);
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G4DynamicParticle* aLept = nullptr; // lepton lv
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G4int Z = targetNucleus.GetZ_asInt();
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G4int A = targetNucleus.GetA_asInt();
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G4double mTarg = targetNucleus.AtomicMass(A,Z);
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G4int pdgP(0), qB(0);
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// G4double mSum = G4ParticleTable::GetParticleTable()->FindParticle(2212)->GetPDGMass() + mPip;
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G4int iPi = GetOnePionIndex(energy);
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G4double p1pi = GetNuMuOnePionProb( iPi, energy);
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if( p1pi > G4UniformRand() && fCosTheta > 0.9 ) // && fQtransfer < 0.95*GeV ) // mu- & coherent pion + nucleus
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{
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// lvsum = lvp1 + lvpip1;
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lvsum = lvp1 + lvt1;
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// cost = fCosThetaPi;
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cost = fCosTheta;
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sint = std::sqrt( (1.0 - cost)*(1.0 + cost) );
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phi = G4UniformRand()*CLHEP::twopi;
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eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost );
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// muMom = sqrt(fEmuPi*fEmuPi-fMnumu*fMnumu);
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muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu);
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eP *= muMom;
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// lv2 = G4LorentzVector( eP, fEmuPi );
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lv2 = G4LorentzVector( eP, fEmu );
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lv2 = fLVl;
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lvX = lvsum - lv2;
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lvX = fLVh;
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massX2 = lvX.m2();
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G4double massX = lvX.m();
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G4double massR = fLVt.m();
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// if ( massX2 <= 0. ) // vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved
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if ( massX2 <= fM1*fM1 ) // 9-3-20 vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved
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if ( lvX.e() <= fM1 ) // 9-3-20 vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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fW2 = massX2;
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if( pName == "nu_mu" ) aLept = new G4DynamicParticle( theNuMu, lv2 );
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else if( pName == "anti_nu_mu") aLept = new G4DynamicParticle( theANuMu, lv2 );
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else
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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pdgP = 111;
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G4double eCut; // = fMpi + 0.5*(fMpi*fMpi - massX2)/mTarg; // massX -> fMpi
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if( A > 1 )
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{
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eCut = (fMpi + mTarg)*(fMpi + mTarg) - (massX + massR)*(massX + massR);
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eCut /= 2.*massR;
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eCut += massX;
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}
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else eCut = fM1 + fMpi;
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if ( lvX.e() > eCut ) // && sqrt( GetW2() ) < 1.4*GeV ) //
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{
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CoherentPion( lvX, pdgP, targetNucleus);
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}
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else
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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theParticleChange.AddSecondary( aLept, fSecID );
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return &theParticleChange;
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}
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else // lepton part in lab
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{
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lvsum = lvp1 + lvt1;
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cost = fCosTheta;
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sint = std::sqrt( (1.0 - cost)*(1.0 + cost) );
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phi = G4UniformRand()*CLHEP::twopi;
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eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost );
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muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu);
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eP *= muMom;
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lv2 = G4LorentzVector( eP, fEmu );
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lvX = lvsum - lv2;
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massX2 = lvX.m2();
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if ( massX2 <= 0. ) // vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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fW2 = massX2;
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aLept = new G4DynamicParticle( theNuMu, lv2 );
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theParticleChange.AddSecondary( aLept, fSecID );
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}
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// hadron part
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fRecoil = nullptr;
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fCascade = false;
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fString = false;
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if( A == 1 )
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{
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qB = 1;
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// if( G4UniformRand() > 0.1 ) // > 0.9999 ) // > 0.0001 ) //
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{
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ClusterDecay( lvX, qB );
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}
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return &theParticleChange;
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}
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G4Nucleus recoil;
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G4double rM(0.), ratio = G4double(Z)/G4double(A);
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if( ratio > G4UniformRand() ) // proton is excited
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{
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fProton = true;
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recoil = G4Nucleus(A-1,Z-1);
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fRecoil = &recoil;
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rM = recoil.AtomicMass(A-1,Z-1);
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fMt = G4ParticleTable::GetParticleTable()->FindParticle(2212)->GetPDGMass()
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+ G4ParticleTable::GetParticleTable()->FindParticle(111)->GetPDGMass();
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}
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else // excited neutron
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{
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fProton = false;
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recoil = G4Nucleus(A-1,Z);
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fRecoil = &recoil;
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rM = recoil.AtomicMass(A-1,Z);
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fMt = G4ParticleTable::GetParticleTable()->FindParticle(2112)->GetPDGMass()
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+ G4ParticleTable::GetParticleTable()->FindParticle(111)->GetPDGMass();
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}
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// G4int index = GetEnergyIndex(energy);
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G4int nepdg = aParticle->GetDefinition()->GetPDGEncoding();
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G4double qeTotRat; // = GetNuMuQeTotRat(index, energy);
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qeTotRat = CalculateQEratioA( Z, A, energy, nepdg);
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G4ThreeVector dX = (lvX.vect()).unit();
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G4double eX = lvX.e(); // excited nucleon
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G4double mX = sqrt(massX2);
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if( qeTotRat > G4UniformRand() || mX <= fMt ) // || eX <= 1232.*MeV) // QE
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{
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fString = false;
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if( fProton )
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{
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fPDGencoding = 2212;
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fMr = proton_mass_c2;
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recoil = G4Nucleus(A-1,Z-1);
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fRecoil = &recoil;
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rM = recoil.AtomicMass(A-1,Z-1);
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}
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else
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{
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fPDGencoding = 2112;
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fMr = G4ParticleTable::GetParticleTable()->
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FindParticle(fPDGencoding)->GetPDGMass(); // 939.5654133*MeV;
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recoil = G4Nucleus(A-1,Z);
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fRecoil = &recoil;
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rM = recoil.AtomicMass(A-1,Z);
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}
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G4double eTh = fMr+0.5*(fMr*fMr-mX*mX)/rM;
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if(eX <= eTh) // vmg, very rarely out of kinematics
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{
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theParticleChange.SetEnergyChange(energy);
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theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit());
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return &theParticleChange;
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}
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FinalBarion( lvX, 0, fPDGencoding ); // p(n)+deexcited recoil
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}
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else // if ( eX < 9500000.*GeV ) // < 25.*GeV) // < 95.*GeV ) // < 2.5*GeV ) //cluster decay
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{
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if ( fProton && pName == "nu_mu" ) qB = 1;
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else if( !fProton && pName == "nu_mu" ) qB = 0;
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ClusterDecay( lvX, qB );
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}
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return &theParticleChange;
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}
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/////////////////////////////////////////////////////////////////////
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////////////////////////////////////////////////////////////////////
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///////////////////////////////////////////////////////////////////
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/////////////////////////////////////////////////
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//
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// sample x, then Q2
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void G4NuMuNucleusNcModel::SampleLVkr(const G4HadProjectile & aTrack, G4Nucleus& targetNucleus)
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{
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fBreak = false;
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G4int A = targetNucleus.GetA_asInt(), iTer(0), iTerMax(100);
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G4int Z = targetNucleus.GetZ_asInt();
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G4double e3(0.), pMu2(0.), pX2(0.), nMom(0.), rM(0.), hM(0.), tM = targetNucleus.AtomicMass(A,Z);
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G4double cost(1.), sint(0.), phi(0.), muMom(0.);
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G4ThreeVector eP, bst;
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const G4HadProjectile* aParticle = &aTrack;
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G4LorentzVector lvp1 = aParticle->Get4Momentum();
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nMom = NucleonMomentum( targetNucleus );
|
|
|
|
if( A == 1 || nMom == 0. ) // hydrogen, no Fermi motion ???
|
|
{
|
|
fNuEnergy = aParticle->GetTotalEnergy();
|
|
iTer = 0;
|
|
|
|
do
|
|
{
|
|
fXsample = SampleXkr(fNuEnergy);
|
|
fQtransfer = SampleQkr(fNuEnergy, fXsample);
|
|
fQ2 = fQtransfer*fQtransfer;
|
|
|
|
if( fXsample > 0. )
|
|
{
|
|
fW2 = fM1*fM1 - fQ2 + fQ2/fXsample; // sample excited hadron mass
|
|
fEmu = fNuEnergy - fQ2/2./fM1/fXsample;
|
|
}
|
|
else
|
|
{
|
|
fW2 = fM1*fM1;
|
|
fEmu = fNuEnergy;
|
|
}
|
|
e3 = fNuEnergy + fM1 - fEmu;
|
|
|
|
// if( e3 < sqrt(fW2) ) G4cout<<"energyX = "<<e3/GeV<<", fW = "<<sqrt(fW2)/GeV<<G4endl; // vmg ~10^-5 for NC
|
|
|
|
pMu2 = fEmu*fEmu - fMnumu*fMnumu;
|
|
pX2 = e3*e3 - fW2;
|
|
|
|
fCosTheta = fNuEnergy*fNuEnergy + pMu2 - pX2;
|
|
fCosTheta /= 2.*fNuEnergy*sqrt(pMu2);
|
|
iTer++;
|
|
}
|
|
while( ( abs(fCosTheta) > 1. || fEmu < fMnumu ) && iTer < iTerMax );
|
|
|
|
if( iTer >= iTerMax ) { fBreak = true; return; }
|
|
|
|
if( abs(fCosTheta) > 1.) // vmg: due to big Q2/x values. To be improved ...
|
|
{
|
|
G4cout<<"H2: fCosTheta = "<<fCosTheta<<", fEmu = "<<fEmu<<G4endl;
|
|
// fCosTheta = -1. + 2.*G4UniformRand();
|
|
if(fCosTheta < -1.) fCosTheta = -1.;
|
|
if(fCosTheta > 1.) fCosTheta = 1.;
|
|
}
|
|
// LVs
|
|
|
|
G4LorentzVector lvt1 = G4LorentzVector( 0., 0., 0., fM1 );
|
|
G4LorentzVector lvsum = lvp1 + lvt1;
|
|
|
|
cost = fCosTheta;
|
|
sint = std::sqrt( (1.0 - cost)*(1.0 + cost) );
|
|
phi = G4UniformRand()*CLHEP::twopi;
|
|
eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost );
|
|
muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu);
|
|
eP *= muMom;
|
|
fLVl = G4LorentzVector( eP, fEmu );
|
|
|
|
fLVh = lvsum - fLVl;
|
|
fLVt = G4LorentzVector( 0., 0., 0., 0. ); // no recoil
|
|
}
|
|
else // Fermi motion, Q2 in nucleon rest frame
|
|
{
|
|
G4ThreeVector nMomDir = nMom*G4RandomDirection();
|
|
|
|
if( !f2p2h ) // 1p1h
|
|
{
|
|
G4Nucleus recoil(A-1,Z);
|
|
rM = sqrt( recoil.AtomicMass(A-1,Z)*recoil.AtomicMass(A-1,Z) + nMom*nMom );
|
|
hM = tM - rM;
|
|
|
|
fLVt = G4LorentzVector( nMomDir, sqrt( rM*rM+nMom*nMom ) );
|
|
fLVh = G4LorentzVector(-nMomDir, sqrt( hM*hM+nMom*nMom ) );
|
|
}
|
|
else // 2p2h
|
|
{
|
|
G4Nucleus recoil(A-2,Z-1);
|
|
rM = recoil.AtomicMass(A-2,Z-1)+sqrt(nMom*nMom+fM1*fM1);
|
|
hM = tM - rM;
|
|
|
|
fLVt = G4LorentzVector( nMomDir, sqrt( rM*rM+nMom*nMom ) );
|
|
fLVh = G4LorentzVector(-nMomDir, sqrt( hM*hM+nMom*nMom ) );
|
|
}
|
|
// G4cout<<hM<<", ";
|
|
// bst = fLVh.boostVector(); // 9-3-20
|
|
|
|
// lvp1.boost(-bst); // 9-3-20 -> nucleon rest system, where Q2 transfer is ???
|
|
|
|
fNuEnergy = lvp1.e();
|
|
iTer = 0;
|
|
|
|
do
|
|
{
|
|
fXsample = SampleXkr(fNuEnergy);
|
|
fQtransfer = SampleQkr(fNuEnergy, fXsample);
|
|
fQ2 = fQtransfer*fQtransfer;
|
|
|
|
if( fXsample > 0. )
|
|
{
|
|
fW2 = fM1*fM1 - fQ2 + fQ2/fXsample; // sample excited hadron mass
|
|
fEmu = fNuEnergy - fQ2/2./fM1/fXsample;
|
|
}
|
|
else
|
|
{
|
|
fW2 = fM1*fM1;
|
|
fEmu = fNuEnergy;
|
|
}
|
|
|
|
// if(fEmu < 0.) G4cout<<"fEmu = "<<fEmu<<" hM = "<<hM<<G4endl;
|
|
|
|
e3 = fNuEnergy + fM1 - fEmu;
|
|
|
|
// if( e3 < sqrt(fW2) ) G4cout<<"energyX = "<<e3/GeV<<", fW = "<<sqrt(fW2)/GeV<<G4endl;
|
|
|
|
pMu2 = fEmu*fEmu - fMnumu*fMnumu;
|
|
pX2 = e3*e3 - fW2;
|
|
|
|
fCosTheta = fNuEnergy*fNuEnergy + pMu2 - pX2;
|
|
fCosTheta /= 2.*fNuEnergy*sqrt(pMu2);
|
|
iTer++;
|
|
}
|
|
while( ( abs(fCosTheta) > 1. || fEmu < fMnumu ) && iTer < iTerMax );
|
|
|
|
if( iTer >= iTerMax ) { fBreak = true; return; }
|
|
|
|
if( abs(fCosTheta) > 1.) // vmg: due to big Q2/x values. To be improved ...
|
|
{
|
|
G4cout<<"FM: fCosTheta = "<<fCosTheta<<", fEmu = "<<fEmu<<G4endl;
|
|
// fCosTheta = -1. + 2.*G4UniformRand();
|
|
if(fCosTheta < -1.) fCosTheta = -1.;
|
|
if(fCosTheta > 1.) fCosTheta = 1.;
|
|
}
|
|
// LVs
|
|
G4LorentzVector lvt1 = G4LorentzVector( 0., 0., 0., fM1 );
|
|
G4LorentzVector lvsum = lvp1 + lvt1;
|
|
|
|
cost = fCosTheta;
|
|
sint = std::sqrt( (1.0 - cost)*(1.0 + cost) );
|
|
phi = G4UniformRand()*CLHEP::twopi;
|
|
eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost );
|
|
muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu);
|
|
eP *= muMom;
|
|
fLVl = G4LorentzVector( eP, fEmu );
|
|
fLVh = lvsum - fLVl;
|
|
// back to lab system
|
|
// fLVl.boost(bst); // 9-3-20
|
|
// fLVh.boost(bst); // 9-3-20
|
|
}
|
|
//G4cout<<iTer<<", "<<fBreak<<"; ";
|
|
}
|
|
|
|
//
|
|
//
|
|
///////////////////////////
|