Gabriele Cosmo
146 lines
4.9 KiB
Plaintext
146 lines
4.9 KiB
Plaintext
// This code implementation is the intellectual property of
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// the GEANT4 collaboration.
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//
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// By copying, distributing or modifying the Program (or any work
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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: G4GammaConversion.icc,v 1.2 1999/12/15 14:51:45 gunter Exp $
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// GEANT4 tag $Name: geant4-03-00 $
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//
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//
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// ---------------------------------------------------------------
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// GEANT 4 class inlined methods file
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//
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// For information related to this code contact:
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// CERN, CN Division, ASD group
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// History: first implementation, based on object model of
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// 2nd December 1995, G.Cosmo
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// ------------ G4GammaConversion physics process ---------
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// by Michel Maire, 24 May 1996
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// ***************************************************************
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// 11-06-96, in GetMeanFreePath() the partial sum is stored, by M.Maire
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// 16-09-96, dynamical array PartialSumSigma, by M.Maire
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// 13-12-96, Sign corrected in the ScreenFunctions, by L.Urban
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// 14-01-97, crossection table + meanfreepath table.
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// PartialSumSigma removed, by M.Maire
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// 14-01-97, new physics scheme for geant4alpha, M.Maire
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// ---------------------------------------------------------------
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4bool G4GammaConversion::IsApplicable(const G4ParticleDefinition& particle)
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{
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return ( &particle == G4Gamma::Gamma() );
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4double G4GammaConversion::GetMicroscopicCrossSection(
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const G4DynamicParticle* aDynamicGamma,
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G4Element* anElement)
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// gives the microscopic total cross section in GEANT4 internal units
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{
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G4double crossSection;
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G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
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G4bool isOutRange ;
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if (GammaEnergy < LowestEnergyLimit)
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crossSection = 0. ;
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else {
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if (GammaEnergy > HighestEnergyLimit) GammaEnergy = 0.99*HighestEnergyLimit ;
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crossSection = (*theCrossSectionTable)(anElement->GetIndex())->
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GetValue( GammaEnergy, isOutRange );
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}
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return crossSection;
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4double G4GammaConversion::GetMeanFreePath(const G4Track& aTrack,
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G4double,
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G4ForceCondition*)
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// returns the photon mean free path in GEANT4 internal units
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// (MeanFreePath is a private member of the class)
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{
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const G4DynamicParticle* aDynamicGamma = aTrack.GetDynamicParticle();
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G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
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G4Material* aMaterial = aTrack.GetMaterial();
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G4bool isOutRange ;
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if (GammaEnergy < LowestEnergyLimit)
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MeanFreePath = DBL_MAX;
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else {
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if (GammaEnergy > HighestEnergyLimit) GammaEnergy = 0.99*HighestEnergyLimit ;
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MeanFreePath = (*theMeanFreePathTable)(aMaterial->GetIndex())->
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GetValue( GammaEnergy, isOutRange );
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}
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return MeanFreePath;
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4double G4GammaConversion::ComputeMeanFreePath(G4double GammaEnergy,
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G4Material* aMaterial)
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// computes and returns the photon mean free path in GEANT4 internal units
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{
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const G4ElementVector* theElementVector = aMaterial->GetElementVector() ;
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const G4double* theAtomNumDensityVector = aMaterial->GetAtomicNumDensityVector();
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G4double SIGMA = 0 ;
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for ( G4int i=0 ; i < aMaterial->GetNumberOfElements() ; i++ )
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{
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SIGMA += theAtomNumDensityVector[i] *
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ComputeMicroscopicCrossSection(GammaEnergy,
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(*theElementVector)(i)->GetZ() );
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}
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return SIGMA > DBL_MIN ? 1./SIGMA : DBL_MAX;
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4double G4GammaConversion::ScreenFunction1(G4double ScreenVariable)
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// compute the value of the screening function 3*PHI1 - PHI2
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{
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G4double screenVal;
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if (ScreenVariable > 1.)
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screenVal = 42.24 - 8.368*log(ScreenVariable+0.952);
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else
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screenVal = 42.392 - ScreenVariable* (7.796 - 1.961*ScreenVariable);
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return screenVal;
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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inline G4double G4GammaConversion::ScreenFunction2(G4double ScreenVariable)
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// compute the value of the screening function 1.5*PHI1 - 0.5*PHI2
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{
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G4double screenVal;
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if (ScreenVariable > 1.)
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screenVal = 42.24 - 8.368*log(ScreenVariable+0.952);
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else
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screenVal = 41.405 - ScreenVariable* (5.828 - 0.8945*ScreenVariable);
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return screenVal;
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}
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//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
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