Import Geant4 0.1.0 source tree
This commit is contained in:
Gabriele Cosmo
@@ -5,8 +5,8 @@
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// based on the Program) you indicate your acceptance of this statement,
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// and all its terms.
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//
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// $Id: G4ionIonisation.cc,v 2.1 1998/12/08 17:12:19 urban Exp $
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// GEANT4 tag $Name: geant4-00 $
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// $Id: G4ionIonisation.cc,v 1.3 1999/04/15 16:04:10 urban Exp $
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// GEANT4 tag $Name: geant4-00-01 $
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//
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// -------------------------------------------------------------
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// GEANT 4 class implementation file
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@@ -28,12 +28,88 @@
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// constructor and destructor
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G4ionIonisation::G4ionIonisation(const G4String& processName)
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: G4hEnergyLoss(processName)
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: G4VContinuousDiscreteProcess(processName),
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ParticleMass(proton_mass_c2),Charge(eplus),
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dEdx(1.*MeV/mm),MinKineticEnergy(1.*keV)
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{ PrintInfoDefinition() ; }
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G4ionIonisation::~G4ionIonisation()
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{ }
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G4double G4ionIonisation::GetConstraints(const G4DynamicParticle *aParticle,
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G4Material *aMaterial)
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{
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// returns the Step limit
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// dRoverRange is the max. allowed relative range loss in one step
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// it calculates dEdx and the range as well....
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const G4double minstep=0.01*mm ;
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G4double KineticEnergy,StepLimit;
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Charge = aParticle->GetDefinition()->GetPDGCharge()/eplus ;
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KineticEnergy = aParticle->GetKineticEnergy();
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G4double massratio=proton_mass_c2/
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aParticle->GetDefinition()->GetPDGMass() ;
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G4double Tscaled= KineticEnergy*massratio ;
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G4double ChargeSquare = Charge*Charge ;
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dEdx=ComputedEdx(aParticle,aMaterial) ;
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StepLimit = 0.2*KineticEnergy/dEdx ;
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if(StepLimit < minstep)
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StepLimit = minstep ;
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return StepLimit ;
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}
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G4VParticleChange* G4ionIonisation::AlongStepDoIt(
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const G4Track& trackData,const G4Step& stepData)
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// compute the energy loss after a step
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{
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const G4DynamicParticle* aParticle;
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G4Material* aMaterial;
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G4double E,finalT,Step,ChargeSquare,MeanLoss ;
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aParticleChange.Initialize(trackData) ;
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aMaterial = trackData.GetMaterial() ;
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// get the actual (true) Step length from stepData
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Step = stepData.GetStepLength() ;
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aParticle = trackData.GetDynamicParticle() ;
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G4double massratio=proton_mass_c2/
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aParticle->GetDefinition()->GetPDGMass() ;
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ChargeSquare = Charge*Charge ;
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G4int index = aMaterial->GetIndex() ;
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E = aParticle->GetKineticEnergy() ;
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if(E < MinKineticEnergy) MeanLoss = E ;
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else
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{
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MeanLoss = Step*dEdx ;
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MeanLoss /= (massratio*ChargeSquare) ;
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}
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finalT = E - MeanLoss ;
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if(finalT < MinKineticEnergy) finalT = 0. ;
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// kill the particle if the kinetic energy <= 0
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if (finalT <= 0. )
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{
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finalT = 0.;
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aParticleChange.SetStatusChange(fStopAndKill);
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}
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aParticleChange.SetEnergyChange( finalT ) ;
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aParticleChange.SetLocalEnergyDeposit(E-finalT) ;
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return &aParticleChange ;
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}
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G4double G4ionIonisation::GetMeanFreePath(
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const G4Track& trackData,
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@@ -50,8 +126,8 @@ G4ionIonisation::~G4ionIonisation()
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aMaterial = trackData.GetMaterial() ;
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G4double KineticEnergy = aParticle->GetKineticEnergy() ;
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G4double ChargeSquare=(aParticle->GetDefinition()->GetPDGCharge())*
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(aParticle->GetDefinition()->GetPDGCharge());
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Charge=(aParticle->GetDefinition()->GetPDGCharge())/eplus;
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G4double ChargeSquare=Charge*Charge ;
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// compute the (macroscopic) cross section first
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@@ -118,6 +194,140 @@ G4double G4ionIonisation::ComputeMicroscopicCrossSection(
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return TotalCrossSection ;
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}
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G4double G4ionIonisation::ComputedEdx(const G4DynamicParticle* aParticle,
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G4Material* material)
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{
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// cuts for electron ....................
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DeltaCutInKineticEnergy = G4Electron::Electron()->GetCutsInEnergy() ;
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G4double KineticEnergy , ionloss ;
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G4double RateMass ;
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G4bool isOutRange ;
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const G4double twoln10 = 2.*log(10.) ;
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const G4double Factor = twopi_mc2_rcl2 ;
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const G4double bg2lim = 0.0169 , taulim = 8.4146e-3 ;
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RateMass = electron_mass_c2/proton_mass_c2 ;
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// get material parameters needed for the energy loss calculation
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G4double ElectronDensity,Eexc,Eexc2,Cden,Mden,Aden,X0den,X1den,taul ;
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G4double* ShellCorrectionVector;
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ElectronDensity = material->GetElectronDensity();
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Eexc = material->GetIonisation()->GetMeanExcitationEnergy();
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Eexc2 = Eexc*Eexc ;
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Cden = material->GetIonisation()->GetCdensity();
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Mden = material->GetIonisation()->GetMdensity();
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Aden = material->GetIonisation()->GetAdensity();
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X0den = material->GetIonisation()->GetX0density();
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X1den = material->GetIonisation()->GetX1density();
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taul = material->GetIonisation()->GetTaul() ;
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ShellCorrectionVector = material->GetIonisation()->
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GetShellCorrectionVector();
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// get elements in the actual material,
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// they are needed for the low energy part ....
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const G4ElementVector* theElementVector=
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material->GetElementVector() ;
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const G4double* theAtomicNumDensityVector=
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material->GetAtomicNumDensityVector() ;
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const G4int NumberOfElements=
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material->GetNumberOfElements() ;
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// get electron cut in kin. energy for the material
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DeltaCutInKineticEnergyNow =
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DeltaCutInKineticEnergy[material->GetIndex()] ;
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// some local variables -------------------
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G4double tau,tau0,Tmax,gamma,bg2,beta2,rcut,delta,x,sh ;
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KineticEnergy=aParticle->GetKineticEnergy();
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tau = KineticEnergy/proton_mass_c2 ;
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if ( tau < taul )
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// low energy part , parametrized energy loss formulae
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{
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ionloss = 0. ;
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// loop for the elements in the material
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for (G4int iel=0; iel<NumberOfElements; iel++)
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{
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const G4Element* element = (*theElementVector)(iel);
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if ( tau < element->GetIonisation()->GetTau0())
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ionloss += theAtomicNumDensityVector[iel]
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*( element->GetIonisation()->GetAlow()*sqrt(tau)
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+element->GetIonisation()->GetBlow()*tau) ;
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else
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ionloss += theAtomicNumDensityVector[iel]
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* element->GetIonisation()->GetClow()/sqrt(tau) ;
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}
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}
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else
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// high energy part , Bethe-Bloch formula
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{
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gamma = tau +1. ;
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bg2 = tau*(tau+2.) ;
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beta2 = bg2/(gamma*gamma) ;
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Tmax = 2.*electron_mass_c2*bg2
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/(1.+2.*gamma*RateMass+RateMass*RateMass) ;
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if ( DeltaCutInKineticEnergyNow < Tmax)
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rcut = DeltaCutInKineticEnergyNow/Tmax ;
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else
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rcut = 1.;
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ionloss = log(2.*electron_mass_c2*bg2*Tmax/Eexc2)
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+log(rcut)-(1.+rcut)*beta2 ;
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// density correction
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x = log(bg2)/twoln10 ;
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if ( x < X0den )
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delta = 0. ;
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else
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{
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delta = twoln10*x - Cden ;
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if ( x < X1den )
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delta += Aden*pow((X1den-x),Mden) ;
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}
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// shell correction
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if ( bg2 > bg2lim ) {
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sh = 0. ;
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x = 1. ;
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for (G4int k=0; k<=2; k++) {
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x *= bg2 ;
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sh += ShellCorrectionVector[k]/x;
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}
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}
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else {
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sh = 0. ;
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x = 1. ;
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for (G4int k=0; k<=2; k++) {
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x *= bg2lim ;
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sh += ShellCorrectionVector[k]/x;
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}
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sh *= log(tau/taul)/log(taulim/taul) ;
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}
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// now you can compute the total ionization loss
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ionloss -= delta + sh ;
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ionloss *= Factor*ElectronDensity/beta2 ;
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}
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if ( ionloss <= 0.)
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ionloss = 0. ;
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dEdx = ionloss ;
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return dEdx ;
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}
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G4VParticleChange* G4ionIonisation::PostStepDoIt(
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