G4VEmProcess.cc

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// $Id$
//
// -------------------------------------------------------------------
//
// GEANT4 Class file
//
//
// File name:     G4VEmProcess
//
// Author:        Vladimir Ivanchenko on base of Laszlo Urban code
//
// Creation date: 01.10.2003
//
// Modifications:
// 30-06-04 make it to be pure discrete process (V.Ivanchenko)
// 30-09-08 optimise integral option (V.Ivanchenko)
// 08-11-04 Migration to new interface of Store/Retrieve tables (V.Ivanchenko)
// 11-03-05 Shift verbose level by 1, add applyCuts and killPrimary flags (VI)
// 14-03-05 Update logic PostStepDoIt (V.Ivanchenko)
// 08-04-05 Major optimisation of internal interfaces (V.Ivanchenko)
// 18-04-05 Use G4ParticleChangeForGamma (V.Ivanchenko)
// 25-07-05 Add protection: integral mode only for charged particles (VI)
// 04-09-05 default lambdaFactor 0.8 (V.Ivanchenko)
// 11-01-06 add A to parameters of ComputeCrossSectionPerAtom (VI)
// 12-09-06 add SetModel() (mma)
// 12-04-07 remove double call to Clear model manager (V.Ivanchenko)
// 27-10-07 Virtual functions moved to source (V.Ivanchenko)
// 24-06-09 Removed hidden bin in G4PhysicsVector (V.Ivanchenko)
// 17-02-10 Added pointer currentParticle (VI)
// 30-05-12 allow Russian roulette, brem splitting (D. Sawkey)
//
// Class Description:
//

// -------------------------------------------------------------------
//
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

#include "G4VEmProcess.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4ProcessManager.hh"
#include "G4LossTableManager.hh"
#include "G4LossTableBuilder.hh"
#include "G4Step.hh"
#include "G4ParticleDefinition.hh"
#include "G4VEmModel.hh"
#include "G4DataVector.hh"
#include "G4PhysicsTable.hh"
#include "G4PhysicsLogVector.hh"
#include "G4VParticleChange.hh"
#include "G4ProductionCutsTable.hh"
#include "G4Region.hh"
#include "G4Gamma.hh"
#include "G4Electron.hh"
#include "G4Positron.hh"
#include "G4PhysicsTableHelper.hh"
#include "G4EmBiasingManager.hh"
#include "G4GenericIon.hh"

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VEmProcess::G4VEmProcess(const G4String& name, G4ProcessType type):
  G4VDiscreteProcess(name, type),
  secondaryParticle(0),
  buildLambdaTable(true),
  numberOfModels(0),
  theLambdaTable(0),
  theLambdaTablePrim(0),
  theDensityFactor(0),
  theDensityIdx(0),
  integral(false),
  applyCuts(false),
  startFromNull(false),
  splineFlag(true),
  currentModel(0),
  particle(0),
  currentParticle(0),
  currentCouple(0)
{
  SetVerboseLevel(1);

  // Size of tables assuming spline
  minKinEnergy = 0.1*keV;
  maxKinEnergy = 10.0*TeV;
  nLambdaBins  = 77;
  minKinEnergyPrim = DBL_MAX;

  // default lambda factor
  lambdaFactor  = 0.8;

  // default limit on polar angle
  polarAngleLimit = 0.0;
  biasFactor = 1.0;

  // particle types
  theGamma     = G4Gamma::Gamma();
  theElectron  = G4Electron::Electron();
  thePositron  = G4Positron::Positron();

  pParticleChange = &fParticleChange;
  secParticles.reserve(5);

  preStepLambda = 0.0;
  mfpKinEnergy  = DBL_MAX;

  modelManager = new G4EmModelManager();
  biasManager  = 0;
  biasFlag     = false; 
  weightFlag   = false;
  (G4LossTableManager::Instance())->Register(this);
  warn = 0;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VEmProcess::~G4VEmProcess()
{
  if(1 < verboseLevel) {
    G4cout << "G4VEmProcess destruct " << GetProcessName() 
           << "  " << this << "  " <<  theLambdaTable <<G4endl;
  }
  Clear();
  if(theLambdaTable) {
    theLambdaTable->clearAndDestroy();
    delete theLambdaTable;
  }
  if(theLambdaTablePrim) {
    theLambdaTablePrim->clearAndDestroy();
    delete theLambdaTablePrim;
  }
  delete modelManager;
  delete biasManager;
  (G4LossTableManager::Instance())->DeRegister(this);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::Clear()
{
  currentCouple = 0;
  preStepLambda = 0.0;
  mfpKinEnergy  = DBL_MAX;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double G4VEmProcess::MinPrimaryEnergy(const G4ParticleDefinition*,
                                        const G4Material*)
{
  return 0.0;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::AddEmModel(G4int order, G4VEmModel* p, 
                              const G4Region* region)
{
  G4VEmFluctuationModel* fm = 0;
  modelManager->AddEmModel(order, p, fm, region);
  if(p) { p->SetParticleChange(pParticleChange); }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::SetModel(G4VEmModel* p, G4int index)
{
  ++warn;
  if(warn < 10) { 
    G4cout << "### G4VEmProcess::SetModel is obsolete method and will be "
           << "removed for the next release." << G4endl;
    G4cout << "    Please, use SetEmModel" << G4endl;
  } 
  G4int n = emModels.size();
  if(index >= n) { for(G4int i=n; i<=index; ++i) {emModels.push_back(0);} }
  emModels[index] = p;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VEmModel* G4VEmProcess::Model(G4int index)
{
  if(warn < 10) { 
    G4cout << "### G4VEmProcess::Model is obsolete method and will be "
           << "removed for the next release." << G4endl;
    G4cout << "    Please, use EmModel" << G4endl;
  } 
  G4VEmModel* p = 0;
  if(index >= 0 && index <  G4int(emModels.size())) { p = emModels[index]; }
  return p;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::SetEmModel(G4VEmModel* p, G4int index)
{
  G4int n = emModels.size();
  if(index >= n) { for(G4int i=n; i<=index; ++i) {emModels.push_back(0);} }
  emModels[index] = p;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VEmModel* G4VEmProcess::EmModel(G4int index)
{
  G4VEmModel* p = 0;
  if(index >= 0 && index <  G4int(emModels.size())) { p = emModels[index]; }
  return p;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::UpdateEmModel(const G4String& nam, 
                                 G4double emin, G4double emax)
{
  modelManager->UpdateEmModel(nam, emin, emax);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VEmModel* G4VEmProcess::GetModelByIndex(G4int idx, G4bool ver)
{
  return modelManager->GetModel(idx, ver);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::PreparePhysicsTable(const G4ParticleDefinition& part)
{
  if(!particle) { SetParticle(&part); }

  if(part.GetParticleType() == "nucleus" && 
     part.GetParticleSubType() == "generic") {

    G4String pname = part.GetParticleName();
    if(pname != "deuteron" && pname != "triton" &&
       pname != "alpha" && pname != "He3" &&
       pname != "alpha+"   && pname != "helium" &&
       pname != "hydrogen") {

      particle = G4GenericIon::GenericIon();
    }
  }

  if(1 < verboseLevel) {
    G4cout << "G4VEmProcess::PreparePhysicsTable() for "
           << GetProcessName()
           << " and particle " << part.GetParticleName()
           << " local particle " << particle->GetParticleName() 
           << G4endl;
  }

  G4LossTableManager* man = G4LossTableManager::Instance();
  G4LossTableBuilder* bld = man->GetTableBuilder();

  man->PreparePhysicsTable(&part, this);

  if(particle == &part) {
    Clear();
    InitialiseProcess(particle);

    const G4ProductionCutsTable* theCoupleTable=
      G4ProductionCutsTable::GetProductionCutsTable();
    size_t n = theCoupleTable->GetTableSize();

    theEnergyOfCrossSectionMax.resize(n, 0.0);
    theCrossSectionMax.resize(n, DBL_MAX);

    // initialisation of models
    numberOfModels = modelManager->NumberOfModels();
    for(G4int i=0; i<numberOfModels; ++i) {
      G4VEmModel* mod = modelManager->GetModel(i);
      if(0 == i) { currentModel = mod; }
      mod->SetPolarAngleLimit(polarAngleLimit);
      if(mod->HighEnergyLimit() > maxKinEnergy) {
        mod->SetHighEnergyLimit(maxKinEnergy);
      }
    }

    if(man->AtomDeexcitation()) { modelManager->SetFluoFlag(true); }
    theCuts = modelManager->Initialise(particle,secondaryParticle,
                                       2.,verboseLevel);
    theCutsGamma    = theCoupleTable->GetEnergyCutsVector(idxG4GammaCut);
    theCutsElectron = theCoupleTable->GetEnergyCutsVector(idxG4ElectronCut);
    theCutsPositron = theCoupleTable->GetEnergyCutsVector(idxG4PositronCut);

    // prepare tables
    if(buildLambdaTable){
      theLambdaTable = G4PhysicsTableHelper::PreparePhysicsTable(theLambdaTable);
      bld->InitialiseBaseMaterials(theLambdaTable);
    }
    // high energy table
    if(minKinEnergyPrim < maxKinEnergy){
      theLambdaTablePrim = 
        G4PhysicsTableHelper::PreparePhysicsTable(theLambdaTablePrim);
      bld->InitialiseBaseMaterials(theLambdaTablePrim);
    }
    // forced biasing
    if(biasManager) { 
      biasManager->Initialise(part,GetProcessName(),verboseLevel); 
      biasFlag = false; 
    }
  }
  theDensityFactor = bld->GetDensityFactors();
  theDensityIdx = bld->GetCoupleIndexes();
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::BuildPhysicsTable(const G4ParticleDefinition& part)
{
  G4String num = part.GetParticleName();
  if(1 < verboseLevel) {
    G4cout << "G4VEmProcess::BuildPhysicsTable() for "
           << GetProcessName()
           << " and particle " << num
           << " buildLambdaTable= " << buildLambdaTable
           << G4endl;
  }

  (G4LossTableManager::Instance())->BuildPhysicsTable(particle);

  if(buildLambdaTable || minKinEnergyPrim < maxKinEnergy) {
    BuildLambdaTable();
  }

  // explicitly defined printout by particle name
  if(1 < verboseLevel || 
     (0 < verboseLevel && (num == "gamma" || num == "e-" || 
                           num == "e+"    || num == "mu+" || 
                           num == "mu-"   || num == "proton"|| 
                           num == "pi+"   || num == "pi-" || 
                           num == "kaon+" || num == "kaon-" || 
                           num == "alpha" || num == "anti_proton" || 
                           num == "GenericIon")))
    { 
      particle = &part;
      PrintInfoDefinition(); 
    }

  if(1 < verboseLevel) {
    G4cout << "G4VEmProcess::BuildPhysicsTable() done for "
           << GetProcessName()
           << " and particle " << num
           << G4endl;
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::BuildLambdaTable()
{
  if(1 < verboseLevel) {
    G4cout << "G4EmProcess::BuildLambdaTable() for process "
           << GetProcessName() << " and particle "
           << particle->GetParticleName() << "  " << this
           << G4endl;
  }

  // Access to materials
  const G4ProductionCutsTable* theCoupleTable=
        G4ProductionCutsTable::GetProductionCutsTable();
  size_t numOfCouples = theCoupleTable->GetTableSize();

  G4LossTableBuilder* bld = (G4LossTableManager::Instance())->GetTableBuilder();

  G4PhysicsLogVector* aVector = 0;
  G4PhysicsLogVector* bVector = 0;
  G4PhysicsLogVector* aVectorPrim = 0;
  G4PhysicsLogVector* bVectorPrim = 0;

  G4double scale = 1.0;
  G4double emax1 = maxKinEnergy;
  if(startFromNull || minKinEnergyPrim < maxKinEnergy ) { 
    scale = std::log(maxKinEnergy/minKinEnergy); 
    if(minKinEnergyPrim < maxKinEnergy) { emax1 = minKinEnergyPrim; }
  }
    
  for(size_t i=0; i<numOfCouples; ++i) {

    if (bld->GetFlag(i)) {

      // create physics vector and fill it
      const G4MaterialCutsCouple* couple = 
        theCoupleTable->GetMaterialCutsCouple(i);

      // build main table
      if(buildLambdaTable) {
        delete (*theLambdaTable)[i];

        G4bool startNull = startFromNull;
        // if start from zero then change the scale
        if(startFromNull || minKinEnergyPrim < maxKinEnergy) {
          G4double emin = MinPrimaryEnergy(particle,couple->GetMaterial());
          if(emin < minKinEnergy) {
            emin = minKinEnergy;
            startNull = false;
          }
          G4double emax = emax1;
          if(emax <= emin) { emax = 2*emin; }
          G4int bin = 
            G4lrint(nLambdaBins*std::log(emax/emin)/scale);
          if(bin < 3) { bin = 3; }
          aVector = new G4PhysicsLogVector(emin, emax, bin);

          // start not from zero
        } else if(!bVector) {
          aVector = 
            new G4PhysicsLogVector(minKinEnergy, maxKinEnergy, nLambdaBins);
          bVector = aVector;
        } else {
          aVector = new G4PhysicsLogVector(*bVector);
        }
        aVector->SetSpline(splineFlag);
        modelManager->FillLambdaVector(aVector, couple, startNull);
        if(splineFlag) { aVector->FillSecondDerivatives(); }
        G4PhysicsTableHelper::SetPhysicsVector(theLambdaTable, i, aVector);
      }
      // build high energy table 
      if(minKinEnergyPrim < maxKinEnergy) { 
        delete (*theLambdaTablePrim)[i];

        // start not from zero
        if(!bVectorPrim) {
          G4int bin = 
            G4lrint(nLambdaBins*std::log(maxKinEnergy/minKinEnergyPrim)/scale);
          if(bin < 3) { bin = 3; }
          aVectorPrim = 
            new G4PhysicsLogVector(minKinEnergyPrim, maxKinEnergy, bin);
          bVectorPrim = aVectorPrim;
        } else {
          aVectorPrim = new G4PhysicsLogVector(*bVectorPrim);
        }
        // always use spline
        aVectorPrim->SetSpline(true);
        modelManager->FillLambdaVector(aVectorPrim, couple, false, 
                                       fIsCrossSectionPrim);
        aVectorPrim->FillSecondDerivatives();
        G4PhysicsTableHelper::SetPhysicsVector(theLambdaTablePrim, i, aVectorPrim);
      }
    }
  }

  if(buildLambdaTable) { FindLambdaMax(); }

  if(1 < verboseLevel) {
    G4cout << "Lambda table is built for "
           << particle->GetParticleName()
           << G4endl;
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::PrintInfoDefinition()
{
  if(verboseLevel > 0) {
    G4cout << G4endl << GetProcessName() << ":   for  "
           << particle->GetParticleName();
    if(integral)  { G4cout << ", integral: 1 "; }
    if(applyCuts) { G4cout << ", applyCuts: 1 "; }
    G4cout << "    SubType= " << GetProcessSubType();;
    if(biasFactor != 1.0) { G4cout << "   BiasingFactor= " << biasFactor; }
    G4cout << G4endl;
    if(buildLambdaTable) {
      size_t length = theLambdaTable->length();
      for(size_t i=0; i<length; ++i) {
        G4PhysicsVector* v = (*theLambdaTable)[i];
        if(v) { 
          G4cout << "      Lambda table from "
                 << G4BestUnit(minKinEnergy,"Energy") 
                 << " to "
                 << G4BestUnit(v->GetMaxEnergy(),"Energy")
                 << " in " << v->GetVectorLength()-1
                 << " bins, spline: " 
                 << splineFlag
                 << G4endl;
          break;
        }
      }
    }
    if(minKinEnergyPrim < maxKinEnergy) {
      size_t length = theLambdaTablePrim->length();
      for(size_t i=0; i<length; ++i) {
        G4PhysicsVector* v = (*theLambdaTablePrim)[i];
        if(v) { 
          G4cout << "      LambdaPrime table from "
                 << G4BestUnit(minKinEnergyPrim,"Energy") 
                 << " to "
                 << G4BestUnit(maxKinEnergy,"Energy")
                 << " in " << v->GetVectorLength()-1
                 << " bins " 
                 << G4endl;
          break;
        }
      }
    }
    PrintInfo();
    modelManager->DumpModelList(verboseLevel);
  }

  if(verboseLevel > 2 && buildLambdaTable) {
    G4cout << "      LambdaTable address= " << theLambdaTable << G4endl;
    if(theLambdaTable) { G4cout << (*theLambdaTable) << G4endl; }
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::StartTracking(G4Track* track)
{
  // reset parameters for the new track
  currentParticle = track->GetParticleDefinition();
  theNumberOfInteractionLengthLeft = -1.0;
  //currentInteractionLength = -1.0;
  //  theInitialNumberOfInteractionLength=-1.0;
  mfpKinEnergy = DBL_MAX; 

  // forced biasing only for primary particles
  if(biasManager) {
    if(0 == track->GetParentID()) {
      // primary particle
      biasFlag = true; 
      biasManager->ResetForcedInteraction(); 
    }
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double G4VEmProcess::PostStepGetPhysicalInteractionLength(
                             const G4Track& track,
                             G4double   previousStepSize,
                             G4ForceCondition* condition)
{
  *condition = NotForced;
  G4double x = DBL_MAX;

  preStepKinEnergy = track.GetKineticEnergy();
  DefineMaterial(track.GetMaterialCutsCouple());
  SelectModel(preStepKinEnergy, currentCoupleIndex);

  if(!currentModel->IsActive(preStepKinEnergy)) { return x; }
 
  // forced biasing only for primary particles
  if(biasManager) {
    if(0 == track.GetParentID()) {
      if(biasFlag && biasManager->ForcedInteractionRegion(currentCoupleIndex)) {
        return biasManager->GetStepLimit(currentCoupleIndex, previousStepSize);
      }
    }
  }

  // compute mean free path
  if(preStepKinEnergy < mfpKinEnergy) {
    if (integral) { ComputeIntegralLambda(preStepKinEnergy); }
    else { preStepLambda = GetCurrentLambda(preStepKinEnergy); }

    // zero cross section
    if(preStepLambda <= 0.0) { 
      theNumberOfInteractionLengthLeft = -1.0;
      currentInteractionLength = DBL_MAX;
    }
  }

  // non-zero cross section
  if(preStepLambda > 0.0) { 

    if (theNumberOfInteractionLengthLeft < 0.0) {

      // beggining of tracking (or just after DoIt of this process)
      ResetNumberOfInteractionLengthLeft();

    } else if(currentInteractionLength < DBL_MAX) {

      // subtract NumberOfInteractionLengthLeft using previous step
      theNumberOfInteractionLengthLeft -= previousStepSize/currentInteractionLength;
      //SubtractNumberOfInteractionLengthLeft(previousStepSize);
      if(theNumberOfInteractionLengthLeft < 0.) {
        theNumberOfInteractionLengthLeft = 0.0;
        //theNumberOfInteractionLengthLeft = perMillion;
      }
    }

    // new mean free path and step limit for the next step
    currentInteractionLength = 1.0/preStepLambda;
    x = theNumberOfInteractionLengthLeft * currentInteractionLength;
#ifdef G4VERBOSE
    if (verboseLevel>2){
      G4cout << "G4VEmProcess::PostStepGetPhysicalInteractionLength ";
      G4cout << "[ " << GetProcessName() << "]" << G4endl; 
      G4cout << " for " << currentParticle->GetParticleName() 
             << " in Material  " <<  currentMaterial->GetName()
             << " Ekin(MeV)= " << preStepKinEnergy/MeV 
             <<G4endl;
      G4cout << " MeanFreePath = " << currentInteractionLength/cm << "[cm]" 
             << " InteractionLength= " << x/cm <<"[cm] " <<G4endl;
    }
#endif
  }
  return x;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VParticleChange* G4VEmProcess::PostStepDoIt(const G4Track& track,
                                              const G4Step& step)
{
  // In all cases clear number of interaction lengths
  theNumberOfInteractionLengthLeft = -1.0;
  mfpKinEnergy = DBL_MAX; 

  fParticleChange.InitializeForPostStep(track);

  // Do not make anything if particle is stopped, the annihilation then
  // should be performed by the AtRestDoIt!
  if (track.GetTrackStatus() == fStopButAlive) { return &fParticleChange; }

  G4double finalT = track.GetKineticEnergy();

  // forced process - should happen only once per track
  if(biasFlag) {
    if(biasManager->ForcedInteractionRegion(currentCoupleIndex)) {
      biasFlag = false;
    }
  }

  // Integral approach
  if (integral) {
    G4double lx = GetLambda(finalT, currentCouple);
    if(preStepLambda<lx && 1 < verboseLevel) {
      G4cout << "WARNING: for " << currentParticle->GetParticleName() 
             << " and " << GetProcessName()
             << " E(MeV)= " << finalT/MeV
             << " preLambda= " << preStepLambda << " < " 
             << lx << " (postLambda) "
             << G4endl;  
    }

    if(preStepLambda*G4UniformRand() > lx) {
      ClearNumberOfInteractionLengthLeft();
      return &fParticleChange;
    }
  }

  SelectModel(finalT, currentCoupleIndex);
  if(!currentModel->IsActive(finalT)) { return &fParticleChange; }

  // define new weight for primary and secondaries
  G4double weight = fParticleChange.GetParentWeight();
  if(weightFlag) { 
    weight /= biasFactor; 
    fParticleChange.ProposeWeight(weight);
  }
  
  /*  
  if(0 < verboseLevel) {
    G4cout << "G4VEmProcess::PostStepDoIt: Sample secondary; E= "
           << finalT/MeV
           << " MeV; model= (" << currentModel->LowEnergyLimit()
           << ", " <<  currentModel->HighEnergyLimit() << ")"
           << G4endl;
  }
  */

  // sample secondaries
  secParticles.clear();
  currentModel->SampleSecondaries(&secParticles, 
                                  currentCouple, 
                                  track.GetDynamicParticle(),
                                  (*theCuts)[currentCoupleIndex]);

  // bremsstrahlung splitting or Russian roulette
  if(biasManager) {
    if(biasManager->SecondaryBiasingRegion(currentCoupleIndex)) {
      G4double eloss = 0.0;
      weight *= biasManager->ApplySecondaryBiasing(secParticles,
                                                   track, currentModel,
                                                   &fParticleChange,
                                                   eloss, currentCoupleIndex, 
                                                   (*theCuts)[currentCoupleIndex],
                                                   step.GetPostStepPoint()->GetSafety());
      if(eloss > 0.0) {
        eloss += fParticleChange.GetLocalEnergyDeposit();
        fParticleChange.ProposeLocalEnergyDeposit(eloss);
      }
    }
  }

  // save secondaries
  G4int num = secParticles.size();
  if(num > 0) {

    fParticleChange.SetNumberOfSecondaries(num);
    G4double edep = fParticleChange.GetLocalEnergyDeposit();
     
    for (G4int i=0; i<num; ++i) {
      if (secParticles[i]) {
        G4DynamicParticle* dp = secParticles[i];
        const G4ParticleDefinition* p = dp->GetParticleDefinition();
        G4double e = dp->GetKineticEnergy();
        G4bool good = true;
        if(applyCuts) {
          if (p == theGamma) {
            if (e < (*theCutsGamma)[currentCoupleIndex]) { good = false; }

          } else if (p == theElectron) {
            if (e < (*theCutsElectron)[currentCoupleIndex]) { good = false; }

          } else if (p == thePositron) {
            if (electron_mass_c2 < (*theCutsGamma)[currentCoupleIndex] &&
                e < (*theCutsPositron)[currentCoupleIndex]) {
              good = false;
              e += 2.0*electron_mass_c2;
            }
          }
          // added secondary if it is good
        }
        if (good) { 
          G4Track* t = new G4Track(dp, track.GetGlobalTime(), track.GetPosition());
          t->SetTouchableHandle(track.GetTouchableHandle());
          t->SetWeight(weight);
          pParticleChange->AddSecondary(t); 
          //G4cout << "Secondary(post step) has weight " << t->GetWeight() 
          //      << ", Ekin= " << t->GetKineticEnergy()/MeV << " MeV" <<G4endl;
        } else {
          delete dp;
          edep += e;
        }
      } 
    }
    fParticleChange.ProposeLocalEnergyDeposit(edep);
  }

  if(0.0 == fParticleChange.GetProposedKineticEnergy() &&
     fAlive == fParticleChange.GetTrackStatus()) {
    if(particle->GetProcessManager()->GetAtRestProcessVector()->size() > 0)
         { fParticleChange.ProposeTrackStatus(fStopButAlive); }
    else { fParticleChange.ProposeTrackStatus(fStopAndKill); }
  }

  //  ClearNumberOfInteractionLengthLeft();
  return &fParticleChange;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4bool G4VEmProcess::StorePhysicsTable(const G4ParticleDefinition* part,
                                       const G4String& directory,
                                             G4bool ascii)
{
  G4bool yes = true;

  if ( theLambdaTable && part == particle) {
    const G4String name = 
      GetPhysicsTableFileName(part,directory,"Lambda",ascii);
    yes = theLambdaTable->StorePhysicsTable(name,ascii);

    if ( yes ) {
      G4cout << "Physics table is stored for " << particle->GetParticleName()
             << " and process " << GetProcessName()
             << " in the directory <" << directory
             << "> " << G4endl;
    } else {
      G4cout << "Fail to store Physics Table for " 
             << particle->GetParticleName()
             << " and process " << GetProcessName()
             << " in the directory <" << directory
             << "> " << G4endl;
    }
  }
  if ( theLambdaTablePrim && part == particle) {
    const G4String name = 
      GetPhysicsTableFileName(part,directory,"LambdaPrim",ascii);
    yes = theLambdaTablePrim->StorePhysicsTable(name,ascii);

    if ( yes ) {
      G4cout << "Physics table prim is stored for " << particle->GetParticleName()
             << " and process " << GetProcessName()
             << " in the directory <" << directory
             << "> " << G4endl;
    } else {
      G4cout << "Fail to store Physics Table Prim for " 
             << particle->GetParticleName()
             << " and process " << GetProcessName()
             << " in the directory <" << directory
             << "> " << G4endl;
    }
  }
  return yes;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.....

G4bool G4VEmProcess::RetrievePhysicsTable(const G4ParticleDefinition* part,
                                          const G4String& directory,
                                          G4bool ascii)
{
  if(1 < verboseLevel) {
    G4cout << "G4VEmProcess::RetrievePhysicsTable() for "
           << part->GetParticleName() << " and process "
           << GetProcessName() << G4endl;
  }
  G4bool yes = true;

  if((!buildLambdaTable && minKinEnergyPrim > maxKinEnergy) 
     || particle != part) { return yes; }

  const G4String particleName = part->GetParticleName();
  G4String filename;

  if(buildLambdaTable) {
    filename = GetPhysicsTableFileName(part,directory,"Lambda",ascii);
    yes = G4PhysicsTableHelper::RetrievePhysicsTable(theLambdaTable,
                                                     filename,ascii);
    if ( yes ) {
      if (0 < verboseLevel) {
        G4cout << "Lambda table for " << particleName 
               << " is Retrieved from <"
               << filename << ">"
               << G4endl;
      }
      if((G4LossTableManager::Instance())->SplineFlag()) {
        size_t n = theLambdaTable->length();
        for(size_t i=0; i<n; ++i) {
          if((* theLambdaTable)[i]) {
            (* theLambdaTable)[i]->SetSpline(true);
          }
        }
      }
    } else {
      if (1 < verboseLevel) {
        G4cout << "Lambda table for " << particleName << " in file <"
               << filename << "> is not exist"
               << G4endl;
      }
    }
  }
  if(minKinEnergyPrim < maxKinEnergy) {
    filename = GetPhysicsTableFileName(part,directory,"LambdaPrim",ascii);
    yes = G4PhysicsTableHelper::RetrievePhysicsTable(theLambdaTablePrim,
                                                     filename,ascii);
    if ( yes ) {
      if (0 < verboseLevel) {
        G4cout << "Lambda table prim for " << particleName 
               << " is Retrieved from <"
               << filename << ">"
               << G4endl;
      }
      if((G4LossTableManager::Instance())->SplineFlag()) {
        size_t n = theLambdaTablePrim->length();
        for(size_t i=0; i<n; ++i) {
          if((* theLambdaTablePrim)[i]) {
            (* theLambdaTablePrim)[i]->SetSpline(true);
          }
        }
      }
    } else {
      if (1 < verboseLevel) {
        G4cout << "Lambda table prim for " << particleName << " in file <"
               << filename << "> is not exist"
               << G4endl;
      }
    }
  }

  return yes;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double 
G4VEmProcess::CrossSectionPerVolume(G4double kineticEnergy,
                                    const G4MaterialCutsCouple* couple)
{
  // Cross section per atom is calculated
  DefineMaterial(couple);
  G4double cross = 0.0;
  if(theLambdaTable) {
    cross = (*theDensityFactor)[currentCoupleIndex]*
      (((*theLambdaTable)[basedCoupleIndex])->Value(kineticEnergy));
  } else {
    SelectModel(kineticEnergy, currentCoupleIndex);
    cross = currentModel->CrossSectionPerVolume(currentMaterial,
                                                currentParticle,kineticEnergy);
  }

  if(cross < 0.0) { cross = 0.0; }
  return cross;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double G4VEmProcess::GetMeanFreePath(const G4Track& track,
                                       G4double,
                                       G4ForceCondition* condition)
{
  *condition = NotForced;
  return G4VEmProcess::MeanFreePath(track);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double G4VEmProcess::MeanFreePath(const G4Track& track)
{
  DefineMaterial(track.GetMaterialCutsCouple());
  preStepLambda = GetCurrentLambda(track.GetKineticEnergy());
  G4double x = DBL_MAX;
  if(0.0 < preStepLambda) { x = 1.0/preStepLambda; }
  return x;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4double 
G4VEmProcess::ComputeCrossSectionPerAtom(G4double kineticEnergy, 
                                         G4double Z, G4double A, G4double cut)
{
  SelectModel(kineticEnergy, currentCoupleIndex);
  G4double x = 0.0;
  if(currentModel) {
    x = currentModel->ComputeCrossSectionPerAtom(currentParticle,kineticEnergy,
                                                 Z,A,cut);
  }
  return x;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::FindLambdaMax()
{
  if(1 < verboseLevel) {
    G4cout << "### G4VEmProcess::FindLambdaMax: " 
           << particle->GetParticleName() 
           << " and process " << GetProcessName() << G4endl; 
  }
  size_t n = theLambdaTable->length();
  G4PhysicsVector* pv;
  G4double e, ss, emax, smax;

  size_t i;

  // first loop on existing vectors
  for (i=0; i<n; ++i) {
    pv = (*theLambdaTable)[i];
    if(pv) {
      size_t nb = pv->GetVectorLength();
      emax = DBL_MAX;
      smax = 0.0;
      if(nb > 0) {
        for (size_t j=0; j<nb; ++j) {
          e = pv->Energy(j);
          ss = (*pv)(j);
          if(ss > smax) {
            smax = ss;
            emax = e;
          }
        }
      }
      theEnergyOfCrossSectionMax[i] = emax;
      theCrossSectionMax[i] = smax;
      if(1 < verboseLevel) {
        G4cout << "For " << particle->GetParticleName() 
               << " Max CS at i= " << i << " emax(MeV)= " << emax/MeV
               << " lambda= " << smax << G4endl;
      }
    }
  }
  // second loop using base materials
  for (i=0; i<n; ++i) {
    pv = (*theLambdaTable)[i];
    if(!pv){
      G4int j = (*theDensityIdx)[i];
      theEnergyOfCrossSectionMax[i] = theEnergyOfCrossSectionMax[j];
      theCrossSectionMax[i] = (*theDensityFactor)[i]*theCrossSectionMax[j];
    }
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4PhysicsVector* 
G4VEmProcess::LambdaPhysicsVector(const G4MaterialCutsCouple*)
{
  G4PhysicsVector* v = 
    new G4PhysicsLogVector(minKinEnergy, maxKinEnergy, nLambdaBins);
  v->SetSpline((G4LossTableManager::Instance())->SplineFlag());
  return v;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

const G4Element* G4VEmProcess::GetCurrentElement() const
{
  const G4Element* elm = 0;
  if(currentModel) {elm = currentModel->GetCurrentElement(); }
  return elm;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::SetCrossSectionBiasingFactor(G4double f, G4bool flag)
{
  if(f > 0.0) { 
    biasFactor = f; 
    weightFlag = flag;
    if(1 < verboseLevel) {
      G4cout << "### SetCrossSectionBiasingFactor: for " 
             << particle->GetParticleName() 
             << " and process " << GetProcessName()
             << " biasFactor= " << f << " weightFlag= " << flag 
             << G4endl; 
    }
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void 
G4VEmProcess::ActivateForcedInteraction(G4double length, const G4String& r,
                                        G4bool flag)
{
  if(!biasManager) { biasManager = new G4EmBiasingManager(); }
  if(1 < verboseLevel) {
    G4cout << "### ActivateForcedInteraction: for " 
           << particle->GetParticleName() 
           << " and process " << GetProcessName()
           << " length(mm)= " << length/mm
           << " in G4Region <" << r 
           << "> weightFlag= " << flag 
           << G4endl; 
  }
  weightFlag = flag;
  biasManager->ActivateForcedInteraction(length, r);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void
G4VEmProcess::ActivateSecondaryBiasing(const G4String& region,
                 G4double factor,
                 G4double energyLimit)
{
  if (0.0 <= factor) {

    // Range cut can be applied only for e-
    if(0.0 == factor && secondaryParticle != G4Electron::Electron())
      { return; }

    if(!biasManager) { biasManager = new G4EmBiasingManager(); }
    biasManager->ActivateSecondaryBiasing(region, factor, energyLimit);
    if(1 < verboseLevel) {
      G4cout << "### ActivateSecondaryBiasing: for "
       << " process " << GetProcessName()
       << " factor= " << factor
       << " in G4Region <" << region
       << "> energyLimit(MeV)= " << energyLimit/MeV
       << G4endl;
    }
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::SetMinKinEnergy(G4double e)
{
  nLambdaBins = G4lrint(nLambdaBins*std::log(maxKinEnergy/e)
                        /std::log(maxKinEnergy/minKinEnergy));
  minKinEnergy = e;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void G4VEmProcess::SetMaxKinEnergy(G4double e)
{
  nLambdaBins = G4lrint(nLambdaBins*std::log(e/minKinEnergy)
                        /std::log(maxKinEnergy/minKinEnergy));
  maxKinEnergy = e;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

---