#include <G4WentzelVIModel.hh>

Inheritance diagram for G4WentzelVIModel:

Public Member Functions
	G4WentzelVIModel (const G4String &nam="WentzelVIUni")

virtual	~G4WentzelVIModel ()

virtual void	Initialise (const G4ParticleDefinition *, const G4DataVector &)

void	StartTracking (G4Track *)

virtual G4double	ComputeCrossSectionPerAtom (const G4ParticleDefinition *, G4double KineticEnergy, G4double AtomicNumber, G4double AtomicWeight=0., G4double cut=DBL_MAX, G4double emax=DBL_MAX)

virtual G4ThreeVector &	SampleScattering (const G4ThreeVector &, G4double safety)

virtual G4double	ComputeTruePathLengthLimit (const G4Track &track, G4double &currentMinimalStep)

virtual G4double	ComputeGeomPathLength (G4double truePathLength)

virtual G4double	ComputeTrueStepLength (G4double geomStepLength)

void	SetFixedCut (G4double)

G4double	GetFixedCut () const

G4WentzelOKandVIxSection *	GetWVICrossSection ()

Public Member Functions inherited from G4VMscModel
	G4VMscModel (const G4String &nam)

virtual	~G4VMscModel ()

virtual void	SampleSecondaries (std::vector< G4DynamicParticle * > , const G4MaterialCutsCouple , const G4DynamicParticle *, G4double tmin, G4double tmax)

void	SetStepLimitType (G4MscStepLimitType)

void	SetLateralDisplasmentFlag (G4bool val)

void	SetRangeFactor (G4double)

void	SetGeomFactor (G4double)

void	SetSkin (G4double)

void	SetSampleZ (G4bool)

G4VEnergyLossProcess *	GetIonisation () const

void	SetIonisation (G4VEnergyLossProcess , const G4ParticleDefinition part)

G4double	ComputeSafety (const G4ThreeVector &position, G4double limit)

G4double	ComputeGeomLimit (const G4Track &, G4double &presafety, G4double limit)

G4double	GetDEDX (const G4ParticleDefinition part, G4double kineticEnergy, const G4MaterialCutsCouple couple)

G4double	GetRange (const G4ParticleDefinition part, G4double kineticEnergy, const G4MaterialCutsCouple couple)

G4double	GetEnergy (const G4ParticleDefinition part, G4double range, const G4MaterialCutsCouple couple)

G4double	GetTransportMeanFreePath (const G4ParticleDefinition *part, G4double kinEnergy)

Public Member Functions inherited from G4VEmModel
	G4VEmModel (const G4String &nam)

virtual	~G4VEmModel ()

virtual void	InitialiseLocal (const G4ParticleDefinition , G4VEmModel masterModel)

virtual void	InitialiseForMaterial (const G4ParticleDefinition , const G4Material )

virtual void	InitialiseForElement (const G4ParticleDefinition *, G4int Z)

virtual G4double	ComputeDEDXPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=DBL_MAX)

virtual G4double	CrossSectionPerVolume (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

virtual G4double	ChargeSquareRatio (const G4Track &)

virtual G4double	GetChargeSquareRatio (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual G4double	GetParticleCharge (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual void	CorrectionsAlongStep (const G4MaterialCutsCouple , const G4DynamicParticle , G4double &eloss, G4double &niel, G4double length)

virtual G4double	Value (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy)

virtual G4double	MinPrimaryEnergy (const G4Material , const G4ParticleDefinition , G4double cut=0.0)

virtual G4double	MinEnergyCut (const G4ParticleDefinition , const G4MaterialCutsCouple )

virtual void	SetupForMaterial (const G4ParticleDefinition , const G4Material , G4double kineticEnergy)

virtual void	DefineForRegion (const G4Region *)

void	InitialiseElementSelectors (const G4ParticleDefinition *, const G4DataVector &)

std::vector < G4EmElementSelector * > *	GetElementSelectors ()

void	SetElementSelectors (std::vector< G4EmElementSelector * > *)

G4double	ComputeDEDX (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=DBL_MAX)

G4double	CrossSection (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4double	ComputeMeanFreePath (const G4ParticleDefinition , G4double kineticEnergy, const G4Material , G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4double	ComputeCrossSectionPerAtom (const G4ParticleDefinition , const G4Element , G4double kinEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4int	SelectIsotopeNumber (const G4Element *)

const G4Element *	SelectRandomAtom (const G4MaterialCutsCouple , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

const G4Element *	SelectRandomAtom (const G4Material , const G4ParticleDefinition , G4double kineticEnergy, G4double cutEnergy=0.0, G4double maxEnergy=DBL_MAX)

G4int	SelectRandomAtomNumber (const G4Material *)

void	SetParticleChange (G4VParticleChange , G4VEmFluctuationModel f=0)

void	SetCrossSectionTable (G4PhysicsTable *, G4bool isLocal)

G4ElementData *	GetElementData ()

G4PhysicsTable *	GetCrossSectionTable ()

G4VEmFluctuationModel *	GetModelOfFluctuations ()

G4VEmAngularDistribution *	GetAngularDistribution ()

void	SetAngularDistribution (G4VEmAngularDistribution *)

G4double	HighEnergyLimit () const

G4double	LowEnergyLimit () const

G4double	HighEnergyActivationLimit () const

G4double	LowEnergyActivationLimit () const

G4double	PolarAngleLimit () const

G4double	SecondaryThreshold () const

G4bool	LPMFlag () const

G4bool	DeexcitationFlag () const

G4bool	ForceBuildTableFlag () const

G4bool	UseAngularGeneratorFlag () const

void	SetAngularGeneratorFlag (G4bool)

void	SetHighEnergyLimit (G4double)

void	SetLowEnergyLimit (G4double)

void	SetActivationHighEnergyLimit (G4double)

void	SetActivationLowEnergyLimit (G4double)

G4bool	IsActive (G4double kinEnergy)

void	SetPolarAngleLimit (G4double)

void	SetSecondaryThreshold (G4double)

void	SetLPMFlag (G4bool val)

void	SetDeexcitationFlag (G4bool val)

void	SetForceBuildTable (G4bool val)

void	SetMasterThread (G4bool val)

G4bool	IsMaster () const

G4double	MaxSecondaryKinEnergy (const G4DynamicParticle *dynParticle)

const G4String &	GetName () const

void	SetCurrentCouple (const G4MaterialCutsCouple *)

const G4Element *	GetCurrentElement () const

Additional Inherited Members
Protected Member Functions inherited from G4VMscModel
G4ParticleChangeForMSC *	GetParticleChangeForMSC (const G4ParticleDefinition *p=0)

G4double	ConvertTrueToGeom (G4double &tLength, G4double &gLength)

Protected Member Functions inherited from G4VEmModel
G4ParticleChangeForLoss *	GetParticleChangeForLoss ()

G4ParticleChangeForGamma *	GetParticleChangeForGamma ()

virtual G4double	MaxSecondaryEnergy (const G4ParticleDefinition *, G4double kineticEnergy)

const G4MaterialCutsCouple *	CurrentCouple () const

void	SetCurrentElement (const G4Element *)

Protected Attributes inherited from G4VMscModel
G4double	facrange

G4double	facgeom

G4double	facsafety

G4double	skin

G4double	dtrl

G4double	lambdalimit

G4double	geomMin

G4double	geomMax

G4ThreeVector	fDisplacement

G4MscStepLimitType	steppingAlgorithm

G4bool	samplez

G4bool	latDisplasment

Protected Attributes inherited from G4VEmModel
G4ElementData *	fElementData

G4VParticleChange *	pParticleChange

G4PhysicsTable *	xSectionTable

const std::vector< G4double > *	theDensityFactor

const std::vector< G4int > *	theDensityIdx

size_t	idxTable

Detailed Description

Definition at line 69 of file G4WentzelVIModel.hh.

Constructor & Destructor Documentation

G4WentzelVIModel::G4WentzelVIModel ( const G4String & nam = "WentzelVIUni" )

Definition at line 74 of file G4WentzelVIModel.cc.

References python.hepunit::eV, G4LossTableManager::Instance(), and python.hepunit::mm.

                                                       :
   G4VMscModel(nam),
   numlimit(0.1),
   currentCouple(0),
   cosThetaMin(1.0),
   inside(false),
   singleScatteringMode(false)
 {
   invsqrt12 = 1./sqrt(12.);
   tlimitminfix = 1.e-6*mm;
   lowEnergyLimit = 1.0*eV;
   particle = 0;
   nelments = 5;
   xsecn.resize(nelments);
   prob.resize(nelments);
   theManager = G4LossTableManager::Instance();
   wokvi = new G4WentzelOKandVIxSection();
   fixedCut = -1.0;
 
   preKinEnergy = tPathLength = zPathLength = lambdaeff = currentRange 
     = xtsec = 0;
   currentMaterialIndex = 0;
   cosThetaMax = cosTetMaxNuc = 1.0;
 
   fParticleChange = 0;
   currentCuts = 0;
   currentMaterial = 0;
 }

G4WentzelVIModel::~G4WentzelVIModel ( )

virtual

Definition at line 105 of file G4WentzelVIModel.cc.

 {
   delete wokvi;
 }

Member Function Documentation

G4double G4WentzelVIModel::ComputeCrossSectionPerAtom	(	const G4ParticleDefinition *	p,
		G4double	KineticEnergy,
		G4double	AtomicNumber,
		G4double	AtomicWeight = `0.`,
		G4double	cut = `DBL_MAX`,
		G4double	emax = `DBL_MAX`
	)

virtual

Reimplemented from G4VEmModel.

Definition at line 135 of file G4WentzelVIModel.cc.

References G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom(), G4VEmModel::CurrentCouple(), FatalException, G4Exception(), G4lrint(), G4WentzelOKandVIxSection::SetupKinematic(), and G4WentzelOKandVIxSection::SetupTarget().

 {
   G4double cross = 0.0;
   if(p != particle) { SetupParticle(p); }
   if(kinEnergy < lowEnergyLimit) { return cross; }
   if(!CurrentCouple()) {
     G4Exception("G4WentzelVIModel::ComputeCrossSectionPerAtom", "em0011",
         FatalException, " G4MaterialCutsCouple is not defined");
     return 0.0;
   }
   DefineMaterial(CurrentCouple());
   cosTetMaxNuc = wokvi->SetupKinematic(kinEnergy, currentMaterial);
   if(cosTetMaxNuc < 1.0) {
     G4double cut = cutEnergy;
     if(fixedCut > 0.0) { cut = fixedCut; }
     cosTetMaxNuc = wokvi->SetupTarget(G4lrint(Z), cut);
     cross = wokvi->ComputeTransportCrossSectionPerAtom(cosTetMaxNuc);
     /*
     if(p->GetParticleName() == "e-")      
     G4cout << "G4WentzelVIModel::CS: Z= " << G4int(Z) << " e(MeV)= " << kinEnergy 
        << " 1-cosN= " << 1 - cosTetMaxNuc << " cross(bn)= " << cross/barn
        << " " << particle->GetParticleName() << G4endl;
     */
   }
   return cross;
 }

G4double G4WentzelVIModel::ComputeGeomPathLength ( G4double truePathLength )

virtual

Reimplemented from G4VMscModel.

Definition at line 276 of file G4WentzelVIModel.cc.

References DBL_MAX, G4Exp(), G4VMscModel::GetEnergy(), G4VMscModel::GetTransportMeanFreePath(), and G4WentzelOKandVIxSection::SetupKinematic().

 {
   tPathLength  = truelength;
   zPathLength  = tPathLength;
 
   if(lambdaeff > 0.0 && lambdaeff != DBL_MAX) {
     G4double tau = tPathLength/lambdaeff;
     //G4cout << "ComputeGeomPathLength: tLength= " << tPathLength
     //   << " Leff= " << lambdaeff << " tau= " << tau << G4endl; 
     // small step
     if(tau < numlimit) {
       zPathLength *= (1.0 - 0.5*tau + tau*tau/6.0);
 
       // medium step
     } else {
       G4double e1 = 0.0;
       if(currentRange > tPathLength) {
     e1 = GetEnergy(particle,currentRange-tPathLength,currentCouple);
       }
       e1 = 0.5*(e1 + preKinEnergy);
       cosTetMaxNuc = wokvi->SetupKinematic(e1, currentMaterial);
       lambdaeff = GetTransportMeanFreePath(particle,e1);
       zPathLength = lambdaeff*(1.0 - G4Exp(-tPathLength/lambdaeff));
     }
   } else { lambdaeff = DBL_MAX; }
   //G4cout<<"Comp.geom: zLength= "<<zPathLength<<" tLength= "<<tPathLength<<G4endl;
   return zPathLength;
 }

G4double G4WentzelVIModel::ComputeTruePathLengthLimit	(	const G4Track &	track,
		G4double &	currentMinimalStep
	)

virtual

Reimplemented from G4VMscModel.

Definition at line 176 of file G4WentzelVIModel.cc.

References G4VMscModel::ComputeGeomLimit(), G4VMscModel::ComputeSafety(), G4VMscModel::ConvertTrueToGeom(), G4VMscModel::facgeom, G4VMscModel::facrange, G4VMscModel::facsafety, fGeomBoundary, fUseDistanceToBoundary, G4Track::GetDynamicParticle(), G4DynamicParticle::GetKineticEnergy(), G4Track::GetMaterialCutsCouple(), G4StepPoint::GetPosition(), G4Step::GetPreStepPoint(), G4ProductionCuts::GetProductionCut(), G4MaterialCutsCouple::GetProductionCuts(), G4Material::GetRadlen(), G4VMscModel::GetRange(), G4StepPoint::GetSafety(), G4Track::GetStep(), G4StepPoint::GetStepStatus(), G4VMscModel::GetTransportMeanFreePath(), G4INCL::Math::max(), G4INCL::Math::min(), G4WentzelOKandVIxSection::SetupKinematic(), G4InuclParticleNames::sp, and G4VMscModel::steppingAlgorithm.

 {
   G4double tlimit = currentMinimalStep;
   const G4DynamicParticle* dp = track.GetDynamicParticle();
   G4StepPoint* sp = track.GetStep()->GetPreStepPoint();
   G4StepStatus stepStatus = sp->GetStepStatus();
   singleScatteringMode = false;
   //G4cout << "G4WentzelVIModel::ComputeTruePathLengthLimit stepStatus= " 
   //     << stepStatus << "  " << track.GetDefinition()->GetParticleName() 
   //     << G4endl;
 
   // initialisation for each step, lambda may be computed from scratch
   preKinEnergy  = dp->GetKineticEnergy();
   DefineMaterial(track.GetMaterialCutsCouple());
   lambdaeff = GetTransportMeanFreePath(particle,preKinEnergy);
   currentRange = GetRange(particle,preKinEnergy,currentCouple);
   cosTetMaxNuc = wokvi->SetupKinematic(preKinEnergy, currentMaterial);
 
   //G4cout << "lambdaeff= " << lambdaeff << " Range= " << currentRange
   //     << " tlimit= " << tlimit << " 1-cost= " << 1 - cosTetMaxNuc << G4endl;
 
   // extra check for abnormal situation
   // this check needed to run MSC with eIoni and eBrem inactivated
   if(tlimit > currentRange) { tlimit = currentRange; }
 
   // stop here if small range particle
   if(inside || tlimit < tlimitminfix) { 
     return ConvertTrueToGeom(tlimit, currentMinimalStep); 
   }
 
   // pre step
   G4double presafety = sp->GetSafety();
   // far from geometry boundary
   if(currentRange < presafety) {
     inside = true;  
     return ConvertTrueToGeom(tlimit, currentMinimalStep);
   }
 
   // compute presafety again if presafety <= 0 and no boundary
   // i.e. when it is needed for optimization purposes
   if(stepStatus != fGeomBoundary && presafety < tlimitminfix) {
     presafety = ComputeSafety(sp->GetPosition(), tlimit); 
     if(currentRange < presafety) {
       inside = true;  
       return ConvertTrueToGeom(tlimit, currentMinimalStep);
     }
   }
   /* 
   G4cout << "e(MeV)= " << preKinEnergy/MeV
      << "  " << particle->GetParticleName() 
      << " CurLimit(mm)= " << tlimit/mm <<" safety(mm)= " << presafety/mm
      << " R(mm)= " <<currentRange/mm
      << " L0(mm^-1)= " << lambdaeff*mm 
      <<G4endl;
   */
 
   // natural limit for high energy
   G4double rlimit = std::max(facrange*currentRange, 
                  0.7*(1.0 - cosTetMaxNuc)*lambdaeff);
 
   // low-energy e-
   if(cosThetaMax > cosTetMaxNuc) {
     rlimit = std::min(rlimit, facsafety*presafety);
   }
    
   // cut correction
   G4double rcut = currentCouple->GetProductionCuts()->GetProductionCut(1);
   //G4cout << "rcut= " << rcut << " rlimit= " << rlimit << " presafety= " 
   // << presafety << " 1-cosThetaMax= " <<1-cosThetaMax 
   //<< " 1-cosTetMaxNuc= " << 1-cosTetMaxNuc << G4endl;
   if(rcut > rlimit) { rlimit = std::min(rlimit, rcut*sqrt(rlimit/rcut)); }
  
   if(rlimit < tlimit) { tlimit = rlimit; }
 
   tlimit = std::max(tlimit, tlimitminfix);
 
   // step limit in infinite media
   tlimit = std::min(tlimit, 50*currentMaterial->GetRadlen()/facgeom);
 
   //compute geomlimit and force few steps within a volume
   if (steppingAlgorithm == fUseDistanceToBoundary 
       && stepStatus == fGeomBoundary) {
 
     G4double geomlimit = ComputeGeomLimit(track, presafety, currentRange);
     tlimit = std::min(tlimit, geomlimit/facgeom);
   } 
 
   /*    
   G4cout << particle->GetParticleName() << " e= " << preKinEnergy
      << " L0= " << lambdaeff << " R= " << currentRange
      << "tlimit= " << tlimit  
      << " currentMinimalStep= " << currentMinimalStep << G4endl;
   */
   return ConvertTrueToGeom(tlimit, currentMinimalStep);
 }

G4double G4WentzelVIModel::ComputeTrueStepLength ( G4double geomStepLength )

virtual

Reimplemented from G4VMscModel.

Definition at line 307 of file G4WentzelVIModel.cc.

References DBL_MAX, G4Log(), G4VMscModel::GetEnergy(), G4VMscModel::GetTransportMeanFreePath(), and G4WentzelOKandVIxSection::SetupKinematic().

 {
   // initialisation of single scattering x-section
   xtsec = 0.0;
   cosThetaMin = cosTetMaxNuc;
   /*  
   G4cout << "ComputeTrueStepLength: Step= " << geomStepLength 
      << "  Lambda= " <<  lambdaeff 
      << " 1-cosThetaMaxNuc= " << 1 - cosTetMaxNuc << G4endl;
   */
   // pathalogical case
   if(lambdaeff == DBL_MAX) { 
     singleScatteringMode = true;
     zPathLength  = geomStepLength;
     tPathLength  = geomStepLength;
     cosThetaMin = 1.0;
 
     // normal case
   } else {
 
     // small step use only single scattering
     static const G4double singleScatLimit = 1.0e-7;
     if(geomStepLength < lambdaeff*singleScatLimit*(1.0 - cosTetMaxNuc)) {
       singleScatteringMode = true;
       cosThetaMin = 1.0;
       zPathLength  = geomStepLength;
       tPathLength  = geomStepLength;
 
       // step defined by transportation 
     } else if(geomStepLength != zPathLength) { 
 
       // step defined by transportation 
       zPathLength  = geomStepLength;
       G4double tau = geomStepLength/lambdaeff;
       tPathLength  = zPathLength*(1.0 + 0.5*tau + tau*tau/3.0); 
 
       // energy correction for a big step
       if(tau > numlimit) {
     G4double e1 = 0.0;
     if(currentRange > tPathLength) {
       e1 = GetEnergy(particle,currentRange-tPathLength,currentCouple);
     }
     e1 = 0.5*(e1 + preKinEnergy);
     cosTetMaxNuc = wokvi->SetupKinematic(e1, currentMaterial);
     lambdaeff = GetTransportMeanFreePath(particle,e1);
     tau = zPathLength/lambdaeff;
       
     if(tau < 0.999999) { tPathLength = -lambdaeff*G4Log(1.0 - tau); } 
     else               { tPathLength = currentRange; }
       }
     }
   }
 
   // check of step length
   // define threshold angle between single and multiple scattering 
   if(!singleScatteringMode) { cosThetaMin = 1.0 - 1.5*tPathLength/lambdaeff; }
 
   // recompute transport cross section - do not change energy
   // anymore - cannot be applied for big steps
   if(cosThetaMin > cosTetMaxNuc) {
 
     // new computation
     G4double cross = ComputeXSectionPerVolume();
     //G4cout << "%%%% cross= " << cross << "  xtsec= " << xtsec << G4endl;
     if(cross <= 0.0) {
       singleScatteringMode = true;
       tPathLength = zPathLength; 
       lambdaeff = DBL_MAX;
       cosThetaMin = 1.0;
     } else if(xtsec > 0.0) {
 
       lambdaeff = 1./cross; 
       G4double tau = zPathLength*cross;
       if(tau < numlimit) { 
     tPathLength = zPathLength*(1.0 + 0.5*tau + tau*tau/3.0); 
       } 
       else if(tau < 0.999999) { tPathLength = -lambdaeff*G4Log(1.0 - tau); } 
       else                    { tPathLength = currentRange; }
 
       if(tPathLength > currentRange) { tPathLength = currentRange; }
     } 
   }
 
   /*     
   G4cout <<"Comp.true: zLength= "<<zPathLength<<" tLength= "<<tPathLength
      <<" Leff(mm)= "<<lambdaeff/mm<<" sig0(1/mm)= " << xtsec <<G4endl;
   G4cout << particle->GetParticleName() << " 1-cosThetaMin= " << 1-cosThetaMin
      << " 1-cosTetMaxNuc= " << 1-cosTetMaxNuc 
      << " e(MeV)= " << preKinEnergy/MeV << "  "  
      << singleScatteringMode << G4endl;
   */
   return tPathLength;
 }

G4double G4WentzelVIModel::GetFixedCut ( ) const

inline

Definition at line 198 of file G4WentzelVIModel.hh.

 {
   return fixedCut;
 }

G4WentzelOKandVIxSection * G4WentzelVIModel::GetWVICrossSection ( )

inline

Definition at line 205 of file G4WentzelVIModel.hh.

 {
   return wokvi;
 }

void G4WentzelVIModel::Initialise	(	const G4ParticleDefinition *	p,
		const G4DataVector &	cuts
	)

virtual

Implements G4VEmModel.

Definition at line 112 of file G4WentzelVIModel.cc.

References G4VMscModel::GetParticleChangeForMSC(), G4WentzelOKandVIxSection::Initialise(), and G4VEmModel::PolarAngleLimit().

 {
   // reset parameters
   SetupParticle(p);
   currentRange = 0.0;
 
   cosThetaMax = cos(PolarAngleLimit());
   //G4cout << "G4WentzelVIModel::Initialise " << p->GetParticleName() << G4endl;
   wokvi->Initialise(p, cosThetaMax);
   /*
   G4cout << "G4WentzelVIModel: " << particle->GetParticleName()
          << "  1-cos(ThetaLimit)= " << 1 - cosThetaMax 
      << G4endl;
   */
   currentCuts = &cuts;
 
   // set values of some data members
   fParticleChange = GetParticleChangeForMSC(p);
 }

G4ThreeVector & G4WentzelVIModel::SampleScattering	(	const G4ThreeVector &	oldDirection,
		G4double	safety
	)

virtual

Reimplemented from G4VMscModel.

Definition at line 404 of file G4WentzelVIModel.cc.

References DBL_MAX, G4VMscModel::fDisplacement, G4Exp(), G4Log(), G4lrint(), G4UniformRand, G4Material::GetElementVector(), G4Material::GetNumberOfElements(), G4VMscModel::latDisplasment, G4ParticleChangeForMSC::ProposeMomentumDirection(), CLHEP::Hep3Vector::rotateUz(), G4WentzelOKandVIxSection::SampleSingleScattering(), CLHEP::Hep3Vector::set(), G4WentzelOKandVIxSection::SetupTarget(), G4INCL::DeJongSpin::shoot(), python.hepunit::twopi, z, and G4InuclParticleNames::z0.

 {
   fDisplacement.set(0.0,0.0,0.0);
   //G4cout << "!##! G4WentzelVIModel::SampleScattering for " 
   //     << particle->GetParticleName() << G4endl;
 
   // ignore scattering for zero step length and energy below the limit
   if(preKinEnergy < lowEnergyLimit || tPathLength <= 0.0) 
     { return fDisplacement; }
   
   G4double invlambda = 0.0;
   if(lambdaeff < DBL_MAX) { invlambda = 0.5/lambdaeff; }
 
   // use average kinetic energy over the step
   G4double cut = (*currentCuts)[currentMaterialIndex];
   if(fixedCut > 0.0) { cut = fixedCut; }
   /*  
   G4cout <<"SampleScat: E0(MeV)= "<< preKinEnergy/MeV
      << " Leff= " << lambdaeff <<" sig0(1/mm)= " << xtsec 
      << " xmsc= " <<  tPathLength*invlambda 
      << " safety= " << safety << G4endl;
   */
 
   // step limit due msc
   G4int nMscSteps = 1;
   G4double x0 = tPathLength;
   G4double z0 = x0*invlambda;
   G4double zzz = 0.0;
 
   // large scattering angle case - two step approach
 
   if(!singleScatteringMode) {
     static const G4double zzmin = 0.05;
     if(z0 > zzmin && safety > tlimitminfix) { 
       x0 *= 0.5; 
       z0 *= 0.5;
       nMscSteps = 2;
     } 
     if(z0 > zzmin) { zzz = G4Exp(-1.0/z0); }
   } 
 
   // step limit due to single scattering
   G4double x1 = 2*tPathLength;
   if(0.0 < xtsec) { x1 = -G4Log(G4UniformRand())/xtsec; }
 
   // no scattering case
   if(singleScatteringMode && x1 > tPathLength)  
     { return fDisplacement; }
 
   const G4ElementVector* theElementVector = 
     currentMaterial->GetElementVector();
   G4int nelm = currentMaterial->GetNumberOfElements();
 
   // geometry
   G4double sint, cost, phi;
   G4ThreeVector temp(0.0,0.0,1.0);
 
   // current position and direction relative to the end point
   // because of magnetic field geometry is computed relatively to the 
   // end point of the step 
   G4ThreeVector dir(0.0,0.0,1.0);
   fDisplacement.set(0.0,0.0,-zPathLength);
 
   G4double mscfac = zPathLength/tPathLength;
 
   // start a loop 
   G4double x2 = x0;
   G4double step, z;
   G4bool singleScat;
   /*
     G4cout << "Start of the loop x1(mm)= " << x1 << "  x2(mm)= " << x2 
     << " 1-cost1= " << 1 - cosThetaMin << "  " << singleScatteringMode 
        << " xtsec= " << xtsec << "  "  << nMscSteps << G4endl;
   */
   do {
 
     //G4cout << "# x1(mm)= "<< x1<< " x2(mm)= "<< x2 << G4endl;
     // single scattering case
     if(singleScatteringMode && x1 > x2) { break; }
 
     // what is next single of multiple?
     if(x1 <= x2) { 
       step = x1;
       singleScat = true;
     } else {
       step = x2;
       singleScat = false;
     }
 
     //G4cout << "# step(mm)= "<< step<< "  singlScat= "<< singleScat << G4endl;
 
     // new position
     fDisplacement += step*mscfac*dir;
 
     if(singleScat) {
 
       // select element
       G4int i = 0;
       if(nelm > 1) {
     G4double qsec = G4UniformRand()*xtsec;
     for (; i<nelm; ++i) { if(xsecn[i] >= qsec) { break; } }
       }
       G4double cosTetM = 
     wokvi->SetupTarget(G4lrint((*theElementVector)[i]->GetZ()), cut);
       //G4cout << "!!! " << cosThetaMin << "  " << cosTetM << "  " 
       //       << prob[i] << G4endl;
       temp = wokvi->SampleSingleScattering(cosThetaMin, cosTetM, prob[i]);
 
       // direction is changed
       temp.rotateUz(dir);
       dir = temp;
 
       // new proposed step length
       x2 -= step; 
       x1  = -G4Log(G4UniformRand())/xtsec; 
 
     // multiple scattering
     } else { 
       --nMscSteps;
       x1 -= step;
       x2  = x0;
 
       // sample z in interval 0 - 1
       do {
     z = -z0*G4Log(1.0 - (1.0 - zzz)*G4UniformRand());
       } while(z > 1.0);
       cost = 1.0 - 2.0*z/*factCM*/;
       if(cost > 1.0)       { cost = 1.0; }
       else if(cost < -1.0) { cost =-1.0; }
       sint = sqrt((1.0 - cost)*(1.0 + cost));
       phi  = twopi*G4UniformRand();
       G4double vx1 = sint*cos(phi);
       G4double vy1 = sint*sin(phi);
 
       // change direction
       temp.set(vx1,vy1,cost);
       temp.rotateUz(dir);
       dir = temp;
 
       // lateral displacement  
       if (latDisplasment && safety > tlimitminfix) {
     G4double rms = invsqrt12*sqrt(2*z0);
     G4double r   = x0*mscfac;
     G4double dx  = r*(0.5*vx1 + rms*G4RandGauss::shoot(0.0,1.0));
     G4double dy  = r*(0.5*vy1 + rms*G4RandGauss::shoot(0.0,1.0));
     G4double dz;
     G4double d   = r*r - dx*dx - dy*dy;
 
     // change position
     if(d >= 0.0)  { 
       dz = sqrt(d) - r; 
       temp.set(dx,dy,dz);
       temp.rotateUz(dir); 
       fDisplacement += temp;
     }
       }
     }
   } while (0 < nMscSteps);
     
   dir.rotateUz(oldDirection);
 
   //G4cout<<"G4WentzelVIModel sampling is done 1-cost= "<< 1.-dir.z()<<G4endl;
   // end of sampling -------------------------------
 
   fParticleChange->ProposeMomentumDirection(dir);
 
   // lateral displacement  
   fDisplacement.rotateUz(oldDirection);
 
   /*            
      G4cout << " r(mm)= " << fDisplacement.mag() 
         << " safety= " << safety
         << " trueStep(mm)= " << tPathLength
         << " geomStep(mm)= " << zPathLength
         << " x= " << fDisplacement.x() 
         << " y= " << fDisplacement.y() 
         << " z= " << fDisplacement.z()
         << G4endl;
   */
 
   //G4cout<< "G4WentzelVIModel::SampleScattering end NewDir= " << dir<< G4endl;
   return fDisplacement;
 }

void G4WentzelVIModel::SetFixedCut ( G4double val )

inline

Definition at line 191 of file G4WentzelVIModel.hh.

 {
   fixedCut = val;
 }

void G4WentzelVIModel::StartTracking ( G4Track * track )

virtual

Reimplemented from G4VEmModel.

Definition at line 168 of file G4WentzelVIModel.cc.

References G4DynamicParticle::GetDefinition(), and G4Track::GetDynamicParticle().

 {
   SetupParticle(track->GetDynamicParticle()->GetDefinition());
   inside = false;
 }

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

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation