G4DNAMillerGreenExcitationModel.cc

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// $Id: G4DNAMillerGreenExcitationModel.cc 92859 2015-09-18 07:58:30Z gcosmo $
// GEANT4 tag $Name:  $
//

#include "G4DNAMillerGreenExcitationModel.hh"
#include "G4SystemOfUnits.hh"
#include "G4DNAChemistryManager.hh"
#include "G4DNAMolecularMaterial.hh"

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using namespace std;

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G4DNAMillerGreenExcitationModel::G4DNAMillerGreenExcitationModel(const G4ParticleDefinition*,
                                                                 const G4String& nam)
    :G4VEmModel(nam),isInitialised(false)
{
    //  nistwater = G4NistManager::Instance()->FindOrBuildMaterial("G4_WATER");
    fpMolWaterDensity = 0;

    nLevels=0;
    kineticEnergyCorrection[0]=0.;
    kineticEnergyCorrection[1]=0.;
    kineticEnergyCorrection[2]=0.;
    kineticEnergyCorrection[3]=0.;

    verboseLevel= 0;
    // Verbosity scale:
    // 0 = nothing
    // 1 = warning for energy non-conservation
    // 2 = details of energy budget
    // 3 = calculation of cross sections, file openings, sampling of atoms
    // 4 = entering in methods

    if( verboseLevel>0 )
    {
        G4cout << "Miller & Green excitation model is constructed " << G4endl;
    }
    fParticleChangeForGamma = 0;

    // Selection of stationary mode

    statCode = false;
}

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

G4DNAMillerGreenExcitationModel::~G4DNAMillerGreenExcitationModel()
{}

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void G4DNAMillerGreenExcitationModel::Initialise(const G4ParticleDefinition* particle,
                                                 const G4DataVector& /*cuts*/)
{

    if (verboseLevel > 3)
        G4cout << "Calling G4DNAMillerGreenExcitationModel::Initialise()" << G4endl;

    // Energy limits

    G4DNAGenericIonsManager *instance;
    instance = G4DNAGenericIonsManager::Instance();
    G4ParticleDefinition* protonDef = G4Proton::ProtonDefinition();
    G4ParticleDefinition* hydrogenDef = instance->GetIon("hydrogen");
    G4ParticleDefinition* alphaPlusPlusDef = instance->GetIon("alpha++");
    G4ParticleDefinition* alphaPlusDef = instance->GetIon("alpha+");
    G4ParticleDefinition* heliumDef = instance->GetIon("helium");

    G4String proton;
    G4String hydrogen;
    G4String alphaPlusPlus;
    G4String alphaPlus;
    G4String helium;

    // LIMITS AND CONSTANTS

    proton = protonDef->GetParticleName();
    lowEnergyLimit[proton] = 10. * eV;
    highEnergyLimit[proton] = 500. * keV;
    
    kineticEnergyCorrection[0] = 1.;
    slaterEffectiveCharge[0][0] = 0.;
    slaterEffectiveCharge[1][0] = 0.;
    slaterEffectiveCharge[2][0] = 0.;
    sCoefficient[0][0] = 0.;
    sCoefficient[1][0] = 0.;
    sCoefficient[2][0] = 0.;

    hydrogen = hydrogenDef->GetParticleName();
    lowEnergyLimit[hydrogen] = 10. * eV;
    highEnergyLimit[hydrogen] = 500. * keV;
    
    kineticEnergyCorrection[0] = 1.;
    slaterEffectiveCharge[0][0] = 0.;
    slaterEffectiveCharge[1][0] = 0.;
    slaterEffectiveCharge[2][0] = 0.;
    sCoefficient[0][0] = 0.;
    sCoefficient[1][0] = 0.;
    sCoefficient[2][0] = 0.;

    alphaPlusPlus = alphaPlusPlusDef->GetParticleName();
    lowEnergyLimit[alphaPlusPlus] = 1. * keV;
    highEnergyLimit[alphaPlusPlus] = 400. * MeV;

    kineticEnergyCorrection[1] = 0.9382723/3.727417;
    slaterEffectiveCharge[0][1]=0.;
    slaterEffectiveCharge[1][1]=0.;
    slaterEffectiveCharge[2][1]=0.;
    sCoefficient[0][1]=0.;
    sCoefficient[1][1]=0.;
    sCoefficient[2][1]=0.;

    alphaPlus = alphaPlusDef->GetParticleName();
    lowEnergyLimit[alphaPlus] = 1. * keV;
    highEnergyLimit[alphaPlus] = 400. * MeV;

    kineticEnergyCorrection[2] = 0.9382723/3.727417;
    slaterEffectiveCharge[0][2]=2.0;

    // Following values provided by M. Dingfelder
    slaterEffectiveCharge[1][2]=2.00;
    slaterEffectiveCharge[2][2]=2.00;
    //
    sCoefficient[0][2]=0.7;
    sCoefficient[1][2]=0.15;
    sCoefficient[2][2]=0.15;

    helium = heliumDef->GetParticleName();
    lowEnergyLimit[helium] = 1. * keV;
    highEnergyLimit[helium] = 400. * MeV;
    
    kineticEnergyCorrection[3] = 0.9382723/3.727417;
    slaterEffectiveCharge[0][3]=1.7;
    slaterEffectiveCharge[1][3]=1.15;
    slaterEffectiveCharge[2][3]=1.15;
    sCoefficient[0][3]=0.5;
    sCoefficient[1][3]=0.25;
    sCoefficient[2][3]=0.25;

    //

    if (particle==protonDef)
    {
        SetLowEnergyLimit(lowEnergyLimit[proton]);
        SetHighEnergyLimit(highEnergyLimit[proton]);
    }

    if (particle==hydrogenDef)
    {
        SetLowEnergyLimit(lowEnergyLimit[hydrogen]);
        SetHighEnergyLimit(highEnergyLimit[hydrogen]);
    }

    if (particle==alphaPlusPlusDef)
    {
        SetLowEnergyLimit(lowEnergyLimit[alphaPlusPlus]);
        SetHighEnergyLimit(highEnergyLimit[alphaPlusPlus]);
    }

    if (particle==alphaPlusDef)
    {
        SetLowEnergyLimit(lowEnergyLimit[alphaPlus]);
        SetHighEnergyLimit(highEnergyLimit[alphaPlus]);
    }

    if (particle==heliumDef)
    {
        SetLowEnergyLimit(lowEnergyLimit[helium]);
        SetHighEnergyLimit(highEnergyLimit[helium]);
    }

    //

    nLevels = waterExcitation.NumberOfLevels();

    //
    if( verboseLevel>0 )
    {
        G4cout << "Miller & Green excitation model is initialized " << G4endl
               << "Energy range: "
               << LowEnergyLimit() / eV << " eV - "
               << HighEnergyLimit() / keV << " keV for "
               << particle->GetParticleName()
               << G4endl;
    }

    // Initialize water density pointer
    fpMolWaterDensity = G4DNAMolecularMaterial::Instance()->GetNumMolPerVolTableFor(G4Material::GetMaterial("G4_WATER"));

    if (isInitialised) { return; }
    fParticleChangeForGamma = GetParticleChangeForGamma();
    isInitialised = true;

}

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G4double G4DNAMillerGreenExcitationModel::CrossSectionPerVolume(const G4Material* material,
                                                                const G4ParticleDefinition* particleDefinition,
                                                                G4double k,
                                                                G4double,
                                                                G4double)
{
    if (verboseLevel > 3)
        G4cout << "Calling CrossSectionPerVolume() of G4DNAMillerGreenExcitationModel" << G4endl;

    // Calculate total cross section for model

    G4DNAGenericIonsManager *instance;
    instance = G4DNAGenericIonsManager::Instance();

    if (
            particleDefinition != G4Proton::ProtonDefinition()
            &&
            particleDefinition != instance->GetIon("hydrogen")
            &&
            particleDefinition != instance->GetIon("alpha++")
            &&
            particleDefinition != instance->GetIon("alpha+")
            &&
            particleDefinition != instance->GetIon("helium")
            )

        return 0;

    G4double lowLim = 0;
    G4double highLim = 0;
    G4double crossSection = 0.;

    G4double waterDensity = (*fpMolWaterDensity)[material->GetIndex()];

    if(waterDensity!= 0.0)
  //  if (material == nistwater || material->GetBaseMaterial() == nistwater)
    {
//        G4cout << "WATER DENSITY = " << waterDensity*G4Material::GetMaterial("G4_WATER")->GetMassOfMolecule()/(g/cm3)
//               << G4endl;
        const G4String& particleName = particleDefinition->GetParticleName();

        std::map< G4String,G4double,std::less<G4String> >::iterator pos1;
        pos1 = lowEnergyLimit.find(particleName);

        if (pos1 != lowEnergyLimit.end())
        {
            lowLim = pos1->second;
        }

        std::map< G4String,G4double,std::less<G4String> >::iterator pos2;
        pos2 = highEnergyLimit.find(particleName);

        if (pos2 != highEnergyLimit.end())
        {
            highLim = pos2->second;
        }

        if (k >= lowLim && k < highLim)
        {
            crossSection = Sum(k,particleDefinition);

            // add ONE or TWO electron-water excitation for alpha+ and helium
            /*
      if ( particleDefinition == instance->GetIon("alpha+")
           ||
           particleDefinition == instance->GetIon("helium")
         )
      {

      G4DNAEmfietzoglouExcitationModel * excitationXS = new G4DNAEmfietzoglouExcitationModel();
          excitationXS->Initialise(G4Electron::ElectronDefinition());

      G4double sigmaExcitation=0;
      G4double tmp =0.;

      if (k*0.511/3728 > 8.23*eV && k*0.511/3728 < 10*MeV ) sigmaExcitation =
        excitationXS->CrossSectionPerVolume(material,G4Electron::ElectronDefinition(),k*0.511/3728,tmp,tmp)
        /material->GetAtomicNumDensityVector()[1];

      if ( particleDefinition == instance->GetIon("alpha+") )
        crossSection = crossSection +  sigmaExcitation ;

      if ( particleDefinition == instance->GetIon("helium") )
        crossSection = crossSection + 2*sigmaExcitation ;

      delete excitationXS;

          // Alternative excitation model

          G4DNABornExcitationModel * excitationXS = new G4DNABornExcitationModel();
          excitationXS->Initialise(G4Electron::ElectronDefinition());

      G4double sigmaExcitation=0;
      G4double tmp=0;

      if (k*0.511/3728 > 9*eV && k*0.511/3728 < 1*MeV ) sigmaExcitation =
        excitationXS->CrossSectionPerVolume(material,G4Electron::ElectronDefinition(),k*0.511/3728,tmp,tmp)
        /material->GetAtomicNumDensityVector()[1];

      if ( particleDefinition == instance->GetIon("alpha+") )
        crossSection = crossSection +  sigmaExcitation ;

      if ( particleDefinition == instance->GetIon("helium") )
        crossSection = crossSection + 2*sigmaExcitation ;

      delete excitationXS;

      }
*/      

        }

        if (verboseLevel > 2)
        {
            G4cout << "__________________________________" << G4endl;
            G4cout << "G4DNAMillerGreenExcitationModel - XS INFO START" << G4endl;
            G4cout << "Kinetic energy(eV)=" << k/eV << " particle : " << particleDefinition->GetParticleName() << G4endl;
            G4cout << "Cross section per water molecule (cm^2)=" << crossSection/cm/cm << G4endl;
            G4cout << "Cross section per water molecule (cm^-1)=" << crossSection*waterDensity/(1./cm) << G4endl;
            //      G4cout << " - Cross section per water molecule (cm^-1)=" << sigma*material->GetAtomicNumDensityVector()[1]/(1./cm) << G4endl;
            G4cout << "G4DNAMillerGreenExcitationModel - XS INFO END" << G4endl;
        }
    }
    else
    {
        if (verboseLevel > 2)
        {
            G4cout << "MillerGreenExcitationModel : WARNING Water density is NULL" << G4endl;
        }
    }

    return crossSection*waterDensity;
    // return crossSection*material->GetAtomicNumDensityVector()[1];

}

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

void G4DNAMillerGreenExcitationModel::SampleSecondaries(std::vector<G4DynamicParticle*>* /*fvect*/,
                                                        const G4MaterialCutsCouple* /*couple*/,
                                                        const G4DynamicParticle* aDynamicParticle,
                                                        G4double,
                                                        G4double)
{

    if (verboseLevel > 3)
        G4cout << "Calling SampleSecondaries() of G4DNAMillerGreenExcitationModel" << G4endl;

    G4double particleEnergy0 = aDynamicParticle->GetKineticEnergy();

    G4int level = RandomSelect(particleEnergy0,aDynamicParticle->GetDefinition());

    //  G4double excitationEnergy = waterExcitation.ExcitationEnergy(level);

    // Dingfelder's excitation levels
    const G4double excitation[]={ 8.17*eV, 10.13*eV, 11.31*eV, 12.91*eV, 14.50*eV};
    G4double excitationEnergy = excitation[level];

    G4double newEnergy = 0.;
    
    if (!statCode) newEnergy = particleEnergy0 - excitationEnergy;

    else newEnergy = particleEnergy0;
    
    if (newEnergy>0)
    {
        fParticleChangeForGamma->ProposeMomentumDirection(aDynamicParticle->GetMomentumDirection());
        fParticleChangeForGamma->SetProposedKineticEnergy(newEnergy);
        fParticleChangeForGamma->ProposeLocalEnergyDeposit(excitationEnergy);

        const G4Track * theIncomingTrack = fParticleChangeForGamma->GetCurrentTrack();
        G4DNAChemistryManager::Instance()->CreateWaterMolecule(eExcitedMolecule,
                                                               level,
                                                               theIncomingTrack);

    }

}

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

G4double G4DNAMillerGreenExcitationModel::GetPartialCrossSection(const G4Material*,
                                          G4int level,
                                          const G4ParticleDefinition* particleDefinition,
                                          G4double kineticEnergy)
{
  return PartialCrossSection(kineticEnergy, level, particleDefinition);
}

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

G4double G4DNAMillerGreenExcitationModel::PartialCrossSection(G4double k, G4int excitationLevel, 
                                                              const G4ParticleDefinition* particleDefinition)
{
    //                               ( ( z * aj ) ^ omegaj ) * ( t - ej ) ^ nu
    // sigma(t) = zEff^2 * sigma0 * --------------------------------------------
    //                               jj ^ ( omegaj + nu ) + t ^ ( omegaj + nu )
    //
    // where t is the kinetic energy corrected by Helium mass over proton mass for Helium ions
    //
    // zEff is:
    //  1 for protons
    //  2 for alpha++
    //  and  2 - c1 S_1s - c2 S_2s - c3 S_2p for alpha+ and He
    //
    // Dingfelder et al., RPC 59, 255-275, 2000 from Miller and Green (1973)
    // Formula (34) and Table 2

    const G4double sigma0(1.E+8 * barn);
    const G4double nu(1.);
    const G4double aj[]={876.*eV, 2084.* eV, 1373.*eV, 692.*eV, 900.*eV};
    const G4double jj[]={19820.*eV, 23490.*eV, 27770.*eV, 30830.*eV, 33080.*eV};
    const G4double omegaj[]={0.85, 0.88, 0.88, 0.78, 0.78};

    // Dingfelder's excitation levels
    const G4double Eliq[5]={ 8.17*eV, 10.13*eV, 11.31*eV, 12.91*eV, 14.50*eV};

    G4int particleTypeIndex = 0;
    G4DNAGenericIonsManager* instance;
    instance = G4DNAGenericIonsManager::Instance();

    if (particleDefinition == G4Proton::ProtonDefinition()) particleTypeIndex=0;
    if (particleDefinition == instance->GetIon("hydrogen")) particleTypeIndex=0;
    if (particleDefinition == instance->GetIon("alpha++")) particleTypeIndex=1;
    if (particleDefinition == instance->GetIon("alpha+")) particleTypeIndex=2;
    if (particleDefinition == instance->GetIon("helium")) particleTypeIndex=3;

    G4double tCorrected;
    tCorrected = k * kineticEnergyCorrection[particleTypeIndex];

    // SI - added protection
    if (tCorrected < Eliq[excitationLevel]) return 0;
    //

    G4int z = 10;

    G4double numerator;
    numerator = std::pow(z * aj[excitationLevel], omegaj[excitationLevel]) *
            std::pow(tCorrected - Eliq[excitationLevel], nu);

    // H case : see S. Uehara et al. IJRB 77, 2, 139-154 (2001) - section 3.3

    if (particleDefinition == instance->GetIon("hydrogen"))
        numerator = std::pow(z * 0.75*aj[excitationLevel], omegaj[excitationLevel]) *
                std::pow(tCorrected - Eliq[excitationLevel], nu);


    G4double power;
    power = omegaj[excitationLevel] + nu;

    G4double denominator;
    denominator = std::pow(jj[excitationLevel], power) + std::pow(tCorrected, power);

    G4double zEff = particleDefinition->GetPDGCharge() / eplus + particleDefinition->GetLeptonNumber();

    zEff -= ( sCoefficient[0][particleTypeIndex] * S_1s(k, Eliq[excitationLevel], slaterEffectiveCharge[0][particleTypeIndex], 1.) +
              sCoefficient[1][particleTypeIndex] * S_2s(k, Eliq[excitationLevel], slaterEffectiveCharge[1][particleTypeIndex], 2.) +
              sCoefficient[2][particleTypeIndex] * S_2p(k, Eliq[excitationLevel], slaterEffectiveCharge[2][particleTypeIndex], 2.) );

    if (particleDefinition == instance->GetIon("hydrogen")) zEff = 1.;

    G4double cross = sigma0 * zEff * zEff * numerator / denominator;


    return cross;
}

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

G4int G4DNAMillerGreenExcitationModel::RandomSelect(G4double k,const G4ParticleDefinition* particle)
{
    G4int i = nLevels;
    G4double value = 0.;
    std::deque<double> values;

    G4DNAGenericIonsManager *instance;
    instance = G4DNAGenericIonsManager::Instance();

    if ( particle == instance->GetIon("alpha++") ||
         particle == G4Proton::ProtonDefinition()||
         particle == instance->GetIon("hydrogen")  ||
         particle == instance->GetIon("alpha+")  ||
         particle == instance->GetIon("helium")
         )
    {
        while (i > 0)
        {
            i--;
            G4double partial = PartialCrossSection(k,i,particle);
            values.push_front(partial);
            value += partial;
        }

        value *= G4UniformRand();

        i = nLevels;

        while (i > 0)
        {
            i--;
            if (values[i] > value) return i;
            value -= values[i];
        }
    }

    /*
  // add ONE or TWO electron-water excitation for alpha+ and helium

  if ( particle == instance->GetIon("alpha+")
       ||
       particle == instance->GetIon("helium")
     )
  {
    while (i>0)
    {
      i--;

          G4DNAEmfietzoglouExcitationModel * excitationXS = new G4DNAEmfietzoglouExcitationModel();
          excitationXS->Initialise(G4Electron::ElectronDefinition());

      G4double sigmaExcitation=0;

      if (k*0.511/3728 > 8.23*eV && k*0.511/3728 < 10*MeV ) sigmaExcitation = excitationXS->PartialCrossSection(k*0.511/3728,i);

      G4double partial = PartialCrossSection(k,i,particle);

      if (particle == instance->GetIon("alpha+")) partial = PartialCrossSection(k,i,particle) + sigmaExcitation;
      if (particle == instance->GetIon("helium")) partial = PartialCrossSection(k,i,particle) + 2*sigmaExcitation;

      values.push_front(partial);
      value += partial;
      delete excitationXS;
    }

    value*=G4UniformRand();

    i=5;
    while (i>0)
    {
      i--;

      if (values[i]>value) return i;

      value-=values[i];
    }
  }
*/

    return 0;
}

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

G4double G4DNAMillerGreenExcitationModel::Sum(G4double k, const G4ParticleDefinition* particle)
{
    G4double totalCrossSection = 0.;

    for (G4int i=0; i<nLevels; i++)
    {
        totalCrossSection += PartialCrossSection(k,i,particle);
    }
    return totalCrossSection;
}

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

G4double G4DNAMillerGreenExcitationModel::S_1s(G4double t,
                                               G4double energyTransferred,
                                               G4double _slaterEffectiveCharge,
                                               G4double shellNumber)
{
    // 1 - e^(-2r) * ( 1 + 2 r + 2 r^2)
    // Dingfelder, in Chattanooga 2005 proceedings, formula (7)

    G4double r = R(t, energyTransferred, _slaterEffectiveCharge, shellNumber);
    G4double value = 1. - std::exp(-2 * r) * ( ( 2. * r + 2. ) * r + 1. );

    return value;
}


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

G4double G4DNAMillerGreenExcitationModel::S_2s(G4double t,
                                               G4double energyTransferred,
                                               G4double _slaterEffectiveCharge,
                                               G4double shellNumber)
{
    // 1 - e^(-2 r) * ( 1 + 2 r + 2 r^2 + 2 r^4)
    // Dingfelder, in Chattanooga 2005 proceedings, formula (8)

    G4double r = R(t, energyTransferred, _slaterEffectiveCharge, shellNumber);
    G4double value =  1. - std::exp(-2 * r) * (((2. * r * r + 2.) * r + 2.) * r + 1.);

    return value;

}

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

G4double G4DNAMillerGreenExcitationModel::S_2p(G4double t,
                                               G4double energyTransferred,
                                               G4double _slaterEffectiveCharge,
                                               G4double shellNumber)
{
    // 1 - e^(-2 r) * ( 1 + 2 r + 2 r^2 + 4/3 r^3 + 2/3 r^4)
    // Dingfelder, in Chattanooga 2005 proceedings, formula (9)

    G4double r = R(t, energyTransferred, _slaterEffectiveCharge, shellNumber);
    G4double value =  1. - std::exp(-2 * r) * (((( 2./3. * r + 4./3.) * r + 2.) * r + 2.) * r  + 1.);

    return value;
}

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

G4double G4DNAMillerGreenExcitationModel::R(G4double t,
                                            G4double energyTransferred,
                                            G4double _slaterEffectiveCharge,
                                            G4double shellNumber)
{
    // tElectron = m_electron / m_alpha * t
    // Dingfelder, in Chattanooga 2005 proceedings, p 4

    G4double tElectron = 0.511/3728. * t;

    // The following is provided by M. Dingfelder
    G4double H = 2.*13.60569172 * eV;
    G4double value = std::sqrt ( 2. * tElectron / H ) / ( energyTransferred / H ) *  (_slaterEffectiveCharge/shellNumber);

    return value;
}