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89a9605df1b6e52f0020a43d18e69f1293af21bf
geant4/source/processes/electromagnetic/standard/src/G4BraggModel.cc
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Gabriele Cosmo 89a9605df1 Import Geant4 9.4.0 source tree
2016-06-09 16:25:56 +02:00

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//
// ********************************************************************
// * License and Disclaimer *
// * *
// * The Geant4 software is copyright of the Copyright Holders of *
// * the Geant4 Collaboration. It is provided under the terms and *
// * conditions of the Geant4 Software License, included in the file *
// * LICENSE and available at http://cern.ch/geant4/license . These *
// * include a list of copyright holders. *
// * *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work make any representation or warranty, express or implied, *
// * regarding this software system or assume any liability for its *
// * use. Please see the license in the file LICENSE and URL above *
// * for the full disclaimer and the limitation of liability. *
// * *
// * This code implementation is the result of the scientific and *
// * technical work of the GEANT4 collaboration. *
// * By using, copying, modifying or distributing the software (or *
// * any work based on the software) you agree to acknowledge its *
// * use in resulting scientific publications, and indicate your *
// * acceptance of all terms of the Geant4 Software license. *
// ********************************************************************
//
// $Id: G4BraggModel.cc,v 1.29 2010/11/05 19:27:26 vnivanch Exp $
// GEANT4 tag $Name: geant4-09-04 $
//
// -------------------------------------------------------------------
//
// GEANT4 Class file
//
//
// File name: G4BraggModel
//
// Author: Vladimir Ivanchenko
//
// Creation date: 03.01.2002
//
// Modifications:
//
// 04-12-02 Fix problem of G4DynamicParticle constructor (V.Ivanchenko)
// 23-12-02 Change interface in order to move to cut per region (V.Ivanchenko)
// 27-01-03 Make models region aware (V.Ivanchenko)
// 13-02-03 Add name (V.Ivanchenko)
// 04-06-03 Fix compilation warnings (V.Ivanchenko)
// 12-09-04 Add lowestKinEnergy and change order of if in DEDX method (VI)
// 11-04-05 Major optimisation of internal interfaces (V.Ivantchenko)
// 16-06-05 Fix problem of chemical formula (V.Ivantchenko)
// 15-02-06 ComputeCrossSectionPerElectron, ComputeCrossSectionPerAtom (mma)
// 25-04-06 Add stopping data from PSTAR (V.Ivanchenko)
// 12-08-08 Added methods GetParticleCharge, GetChargeSquareRatio,
// CorrectionsAlongStep needed for ions(V.Ivanchenko)
// Class Description:
//
// Implementation of energy loss and delta-electron production by
// slow charged heavy particles
// -------------------------------------------------------------------
//
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include "G4BraggModel.hh"
#include "Randomize.hh"
#include "G4Electron.hh"
#include "G4ParticleChangeForLoss.hh"
#include "G4LossTableManager.hh"
#include "G4EmCorrections.hh"
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
using namespace std;
G4BraggModel::G4BraggModel(const G4ParticleDefinition* p, const G4String& nam)
: G4VEmModel(nam),
particle(0),
protonMassAMU(1.007276),
iMolecula(0),
isIon(false),
isInitialised(false)
{
SetHighEnergyLimit(2.0*MeV);
lowestKinEnergy = 1.0*keV;
theZieglerFactor = eV*cm2*1.0e-15;
theElectron = G4Electron::Electron();
expStopPower125 = 0.0;
corr = G4LossTableManager::Instance()->EmCorrections();
if(p) { SetParticle(p); }
else { SetParticle(theElectron); }
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4BraggModel::~G4BraggModel()
{}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::MinEnergyCut(const G4ParticleDefinition*,
const G4MaterialCutsCouple*)
{
return 0.1*keV;
// return couple->GetMaterial()->GetIonisation()->GetMeanExcitationEnergy();
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
void G4BraggModel::Initialise(const G4ParticleDefinition* p,
const G4DataVector&)
{
if(p != particle) { SetParticle(p); }
// always false before the run
SetDeexcitationFlag(false);
if(!isInitialised) {
isInitialised = true;
G4String pname = particle->GetParticleName();
if(particle->GetParticleType() == "nucleus" &&
pname != "deuteron" && pname != "triton") { isIon = true; }
fParticleChange = GetParticleChangeForLoss();
}
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::GetChargeSquareRatio(const G4ParticleDefinition* p,
const G4Material* mat,
G4double kineticEnergy)
{
// this method is called only for ions
G4double q2 = corr->EffectiveChargeSquareRatio(p,mat,kineticEnergy);
GetModelOfFluctuations()->SetParticleAndCharge(p, q2);
return q2*corr->EffectiveChargeCorrection(p,mat,kineticEnergy);
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::GetParticleCharge(const G4ParticleDefinition* p,
const G4Material* mat,
G4double kineticEnergy)
{
// this method is called only for ions, so no check if it is an ion
return corr->GetParticleCharge(p,mat,kineticEnergy);
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::ComputeCrossSectionPerElectron(
const G4ParticleDefinition* p,
G4double kineticEnergy,
G4double cutEnergy,
G4double maxKinEnergy)
{
G4double cross = 0.0;
G4double tmax = MaxSecondaryEnergy(p, kineticEnergy);
G4double maxEnergy = std::min(tmax,maxKinEnergy);
if(cutEnergy < maxEnergy) {
G4double energy = kineticEnergy + mass;
G4double energy2 = energy*energy;
G4double beta2 = kineticEnergy*(kineticEnergy + 2.0*mass)/energy2;
cross = 1.0/cutEnergy - 1.0/maxEnergy - beta2*log(maxEnergy/cutEnergy)/tmax;
cross *= twopi_mc2_rcl2*chargeSquare/beta2;
}
// G4cout << "BR: e= " << kineticEnergy << " tmin= " << cutEnergy
// << " tmax= " << tmax << " cross= " << cross << G4endl;
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::ComputeCrossSectionPerAtom(
const G4ParticleDefinition* p,
G4double kineticEnergy,
G4double Z, G4double,
G4double cutEnergy,
G4double maxEnergy)
{
G4double cross = Z*ComputeCrossSectionPerElectron
(p,kineticEnergy,cutEnergy,maxEnergy);
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::CrossSectionPerVolume(
const G4Material* material,
const G4ParticleDefinition* p,
G4double kineticEnergy,
G4double cutEnergy,
G4double maxEnergy)
{
G4double eDensity = material->GetElectronDensity();
G4double cross = eDensity*ComputeCrossSectionPerElectron
(p,kineticEnergy,cutEnergy,maxEnergy);
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::ComputeDEDXPerVolume(const G4Material* material,
const G4ParticleDefinition* p,
G4double kineticEnergy,
G4double cutEnergy)
{
G4double tmax = MaxSecondaryEnergy(p, kineticEnergy);
G4double tkin = kineticEnergy/massRate;
G4double dedx = 0.0;
if(tkin > lowestKinEnergy) { dedx = DEDX(material, tkin); }
else { dedx = DEDX(material, lowestKinEnergy)*sqrt(tkin/lowestKinEnergy); }
if (cutEnergy < tmax) {
G4double tau = kineticEnergy/mass;
G4double gam = tau + 1.0;
G4double bg2 = tau * (tau+2.0);
G4double beta2 = bg2/(gam*gam);
G4double x = cutEnergy/tmax;
dedx += (log(x) + (1.0 - x)*beta2) * twopi_mc2_rcl2
* (material->GetElectronDensity())/beta2;
}
// now compute the total ionization loss
if (dedx < 0.0) dedx = 0.0 ;
dedx *= chargeSquare;
return dedx;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
void G4BraggModel::SampleSecondaries(vector<G4DynamicParticle*>* vdp,
const G4MaterialCutsCouple*,
const G4DynamicParticle* dp,
G4double xmin,
G4double maxEnergy)
{
G4double tmax = MaxSecondaryKinEnergy(dp);
G4double xmax = std::min(tmax, maxEnergy);
if(xmin >= xmax) { return; }
G4double kineticEnergy = dp->GetKineticEnergy();
G4double energy = kineticEnergy + mass;
G4double energy2 = energy*energy;
G4double beta2 = kineticEnergy*(kineticEnergy + 2.0*mass)/energy2;
G4double grej = 1.0;
G4double deltaKinEnergy, f;
G4ThreeVector direction = dp->GetMomentumDirection();
// sampling follows ...
do {
G4double q = G4UniformRand();
deltaKinEnergy = xmin*xmax/(xmin*(1.0 - q) + xmax*q);
f = 1.0 - beta2*deltaKinEnergy/tmax;
if(f > grej) {
G4cout << "G4BraggModel::SampleSecondary Warning! "
<< "Majorant " << grej << " < "
<< f << " for e= " << deltaKinEnergy
<< G4endl;
}
} while( grej*G4UniformRand() >= f );
G4double deltaMomentum =
sqrt(deltaKinEnergy * (deltaKinEnergy + 2.0*electron_mass_c2));
G4double totMomentum = energy*sqrt(beta2);
G4double cost = deltaKinEnergy * (energy + electron_mass_c2) /
(deltaMomentum * totMomentum);
if(cost > 1.0) cost = 1.0;
G4double sint = sqrt((1.0 - cost)*(1.0 + cost));
G4double phi = twopi * G4UniformRand() ;
G4ThreeVector deltaDirection(sint*cos(phi),sint*sin(phi), cost) ;
deltaDirection.rotateUz(direction);
// Change kinematics of primary particle
kineticEnergy -= deltaKinEnergy;
G4ThreeVector finalP = direction*totMomentum - deltaDirection*deltaMomentum;
finalP = finalP.unit();
fParticleChange->SetProposedKineticEnergy(kineticEnergy);
fParticleChange->SetProposedMomentumDirection(finalP);
// create G4DynamicParticle object for delta ray
G4DynamicParticle* delta = new G4DynamicParticle(theElectron,deltaDirection,
deltaKinEnergy);
vdp->push_back(delta);
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::MaxSecondaryEnergy(const G4ParticleDefinition* pd,
G4double kinEnergy)
{
if(pd != particle) { SetParticle(pd); }
G4double tau = kinEnergy/mass;
G4double tmax = 2.0*electron_mass_c2*tau*(tau + 2.) /
(1. + 2.0*(tau + 1.)*ratio + ratio*ratio);
return tmax;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4bool G4BraggModel::HasMaterial(const G4Material* material)
{
const size_t numberOfMolecula = 11 ;
SetMoleculaNumber(numberOfMolecula) ;
G4String chFormula = material->GetChemicalFormula() ;
// ICRU Report N49, 1993. Power's model for He.
static G4String molName[numberOfMolecula] = {
"Al_2O_3", "CO_2", "CH_4",
"(C_2H_4)_N-Polyethylene", "(C_2H_4)_N-Polypropylene", "(C_8H_8)_N",
"C_3H_8", "SiO_2", "H_2O",
"H_2O-Gas", "Graphite" } ;
// Special treatment for water in gas state
const G4State theState = material->GetState() ;
if( theState == kStateGas && "H_2O" == chFormula) {
chFormula = G4String("H_2O-Gas");
}
// Search for the material in the table
for (size_t i=0; i<numberOfMolecula; i++) {
if (chFormula == molName[i]) {
SetMoleculaNumber(i) ;
return true ;
}
}
return false ;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::StoppingPower(const G4Material* material,
G4double kineticEnergy)
{
G4double ionloss = 0.0 ;
if (iMolecula < 11) {
// The data and the fit from:
// ICRU Report N49, 1993. Ziegler's model for protons.
// Proton kinetic energy for parametrisation (keV/amu)
G4double T = kineticEnergy/(keV*protonMassAMU) ;
static G4double a[11][5] = {
{1.187E+1, 1.343E+1, 1.069E+4, 7.723E+2, 2.153E-2},
{7.802E+0, 8.814E+0, 8.303E+3, 7.446E+2, 7.966E-3},
{7.294E+0, 8.284E+0, 5.010E+3, 4.544E+2, 8.153E-3},
{8.646E+0, 9.800E+0, 7.066E+3, 4.581E+2, 9.383E-3},
{1.286E+1, 1.462E+1, 5.625E+3, 2.621E+3, 3.512E-2},
{3.229E+1, 3.696E+1, 8.918E+3, 3.244E+3, 1.273E-1},
{1.604E+1, 1.825E+1, 6.967E+3, 2.307E+3, 3.775E-2},
{8.049E+0, 9.099E+0, 9.257E+3, 3.846E+2, 1.007E-2},
{4.015E+0, 4.542E+0, 3.955E+3, 4.847E+2, 7.904E-3},
{4.571E+0, 5.173E+0, 4.346E+3, 4.779E+2, 8.572E-3},
{2.631E+0, 2.601E+0, 1.701E+3, 1.279E+3, 1.638E-2} };
static G4double atomicWeight[11] = {
101.96128, 44.0098, 16.0426, 28.0536, 42.0804,
104.1512, 44.665, 60.0843, 18.0152, 18.0152, 12.0};
if ( T < 10.0 ) {
ionloss = a[iMolecula][0] * sqrt(T) ;
} else if ( T < 10000.0 ) {
G4double slow = a[iMolecula][1] * pow(T, 0.45) ;
G4double shigh = log( 1.0 + a[iMolecula][3]/T
+ a[iMolecula][4]*T ) * a[iMolecula][2]/T ;
ionloss = slow*shigh / (slow + shigh) ;
}
if ( ionloss < 0.0) ionloss = 0.0 ;
if ( 10 == iMolecula ) {
if (T < 100.0) {
ionloss *= (1.0+0.023+0.0066*log10(T));
}
else if (T < 700.0) {
ionloss *=(1.0+0.089-0.0248*log10(T-99.));
}
else if (T < 10000.0) {
ionloss *=(1.0+0.089-0.0248*log10(700.-99.));
}
}
ionloss /= atomicWeight[iMolecula];
// pure material (normally not the case for this function)
} else if(1 == (material->GetNumberOfElements())) {
G4double z = material->GetZ() ;
ionloss = ElectronicStoppingPower( z, kineticEnergy ) ;
}
return ionloss;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::ElectronicStoppingPower(G4double z,
G4double kineticEnergy) const
{
G4double ionloss ;
G4int i = G4int(z)-1 ; // index of atom
if(i < 0) i = 0 ;
if(i > 91) i = 91 ;
// The data and the fit from:
// ICRU Report 49, 1993. Ziegler's type of parametrisations.
// Proton kinetic energy for parametrisation (keV/amu)
G4double T = kineticEnergy/(keV*protonMassAMU) ;
static G4double a[92][5] = {
{1.254E+0, 1.440E+0, 2.426E+2, 1.200E+4, 1.159E-1},
{1.229E+0, 1.397E+0, 4.845E+2, 5.873E+3, 5.225E-2},
{1.411E+0, 1.600E+0, 7.256E+2, 3.013E+3, 4.578E-2},
{2.248E+0, 2.590E+0, 9.660E+2, 1.538E+2, 3.475E-2},
{2.474E+0, 2.815E+0, 1.206E+3, 1.060E+3, 2.855E-2},
{2.631E+0, 2.601E+0, 1.701E+3, 1.279E+3, 1.638E-2},
{2.954E+0, 3.350E+0, 1.683E+3, 1.900E+3, 2.513E-2},
{2.652E+0, 3.000E+0, 1.920E+3, 2.000E+3, 2.230E-2},
{2.085E+0, 2.352E+0, 2.157E+3, 2.634E+3, 1.816E-2},
{1.951E+0, 2.199E+0, 2.393E+3, 2.699E+3, 1.568E-2},
// Z= 11-20
{2.542E+0, 2.869E+0, 2.628E+3, 1.854E+3, 1.472E-2},
{3.791E+0, 4.293E+0, 2.862E+3, 1.009E+3, 1.397E-2},
{4.154E+0, 4.739E+0, 2.766E+3, 1.645E+2, 2.023E-2},
{4.914E+0, 5.598E+0, 3.193E+3, 2.327E+2, 1.419E-2},
{3.232E+0, 3.647E+0, 3.561E+3, 1.560E+3, 1.267E-2},
{3.447E+0, 3.891E+0, 3.792E+3, 1.219E+3, 1.211E-2},
{5.301E+0, 6.008E+0, 3.969E+3, 6.451E+2, 1.183E-2},
{5.731E+0, 6.500E+0, 4.253E+3, 5.300E+2, 1.123E-2},
{5.152E+0, 5.833E+0, 4.482E+3, 5.457E+2, 1.129E-2},
{5.521E+0, 6.252E+0, 4.710E+3, 5.533E+2, 1.112E-2},
// Z= 21-30
{5.201E+0, 5.884E+0, 4.938E+3, 5.609E+2, 9.995E-3},
{4.858E+0, 5.489E+0, 5.260E+3, 6.511E+2, 8.930E-3},
{4.479E+0, 5.055E+0, 5.391E+3, 9.523E+2, 9.117E-3},
{3.983E+0, 4.489E+0, 5.616E+3, 1.336E+3, 8.413E-3},
{3.469E+0, 3.907E+0, 5.725E+3, 1.461E+3, 8.829E-3},
{3.519E+0, 3.963E+0, 6.065E+3, 1.243E+3, 7.782E-3},
{3.140E+0, 3.535E+0, 6.288E+3, 1.372E+3, 7.361E-3},
{3.553E+0, 4.004E+0, 6.205E+3, 5.551E+2, 8.763E-3},
{3.696E+0, 4.194E+0, 4.649E+3, 8.113E+1, 2.242E-2},
{4.210E+0, 4.750E+0, 6.953E+3, 2.952E+2, 6.809E-3},
// Z= 31-40
{5.041E+0, 5.697E+0, 7.173E+3, 2.026E+2, 6.725E-3},
{5.554E+0, 6.300E+0, 6.496E+3, 1.100E+2, 9.689E-3},
{5.323E+0, 6.012E+0, 7.611E+3, 2.925E+2, 6.447E-3},
{5.874E+0, 6.656E+0, 7.395E+3, 1.175E+2, 7.684E-3},
{6.658E+0, 7.536E+0, 7.694E+3, 2.223E+2, 6.509E-3},
{6.413E+0, 7.240E+0, 1.185E+4, 1.537E+2, 2.880E-3},
{5.694E+0, 6.429E+0, 8.478E+3, 2.929E+2, 6.087E-3},
{6.339E+0, 7.159E+0, 8.693E+3, 3.303E+2, 6.003E-3},
{6.407E+0, 7.234E+0, 8.907E+3, 3.678E+2, 5.889E-3},
{6.734E+0, 7.603E+0, 9.120E+3, 4.052E+2, 5.765E-3},
// Z= 41-50
{6.901E+0, 7.791E+0, 9.333E+3, 4.427E+2, 5.587E-3},
{6.424E+0, 7.248E+0, 9.545E+3, 4.802E+2, 5.376E-3},
{6.799E+0, 7.671E+0, 9.756E+3, 5.176E+2, 5.315E-3},
{6.109E+0, 6.887E+0, 9.966E+3, 5.551E+2, 5.151E-3},
{5.924E+0, 6.677E+0, 1.018E+4, 5.925E+2, 4.919E-3},
{5.238E+0, 5.900E+0, 1.038E+4, 6.300E+2, 4.758E-3},
// {5.623, 6.354, 7160.0, 337.6, 0.013940}, // Ag Ziegler77
{5.345E+0, 6.038E+0, 6.790E+3, 3.978E+2, 1.676E-2}, // Ag ICRU49
{5.814E+0, 6.554E+0, 1.080E+4, 3.555E+2, 4.626E-3},
{6.229E+0, 7.024E+0, 1.101E+4, 3.709E+2, 4.540E-3},
{6.409E+0, 7.227E+0, 1.121E+4, 3.864E+2, 4.474E-3},
// Z= 51-60
{7.500E+0, 8.480E+0, 8.608E+3, 3.480E+2, 9.074E-3},
{6.979E+0, 7.871E+0, 1.162E+4, 3.924E+2, 4.402E-3},
{7.725E+0, 8.716E+0, 1.183E+4, 3.948E+2, 4.376E-3},
{8.337E+0, 9.425E+0, 1.051E+4, 2.696E+2, 6.206E-3},
{7.287E+0, 8.218E+0, 1.223E+4, 3.997E+2, 4.447E-3},
{7.899E+0, 8.911E+0, 1.243E+4, 4.021E+2, 4.511E-3},
{8.041E+0, 9.071E+0, 1.263E+4, 4.045E+2, 4.540E-3},
{7.488E+0, 8.444E+0, 1.283E+4, 4.069E+2, 4.420E-3},
{7.291E+0, 8.219E+0, 1.303E+4, 4.093E+2, 4.298E-3},
{7.098E+0, 8.000E+0, 1.323E+4, 4.118E+2, 4.182E-3},
// Z= 61-70
{6.909E+0, 7.786E+0, 1.343E+4, 4.142E+2, 4.058E-3},
{6.728E+0, 7.580E+0, 1.362E+4, 4.166E+2, 3.976E-3},
{6.551E+0, 7.380E+0, 1.382E+4, 4.190E+2, 3.877E-3},
{6.739E+0, 7.592E+0, 1.402E+4, 4.214E+2, 3.863E-3},
{6.212E+0, 6.996E+0, 1.421E+4, 4.239E+2, 3.725E-3},
{5.517E+0, 6.210E+0, 1.440E+4, 4.263E+2, 3.632E-3},
{5.220E+0, 5.874E+0, 1.460E+4, 4.287E+2, 3.498E-3},
{5.071E+0, 5.706E+0, 1.479E+4, 4.330E+2, 3.405E-3},
{4.926E+0, 5.542E+0, 1.498E+4, 4.335E+2, 3.342E-3},
{4.788E+0, 5.386E+0, 1.517E+4, 4.359E+2, 3.292E-3},
// Z= 71-80
{4.893E+0, 5.505E+0, 1.536E+4, 4.384E+2, 3.243E-3},
{5.028E+0, 5.657E+0, 1.555E+4, 4.408E+2, 3.195E-3},
{4.738E+0, 5.329E+0, 1.574E+4, 4.432E+2, 3.186E-3},
{4.587E+0, 5.160E+0, 1.541E+4, 4.153E+2, 3.406E-3},
{5.201E+0, 5.851E+0, 1.612E+4, 4.416E+2, 3.122E-3},
{5.071E+0, 5.704E+0, 1.630E+4, 4.409E+2, 3.082E-3},
{4.946E+0, 5.563E+0, 1.649E+4, 4.401E+2, 2.965E-3},
{4.477E+0, 5.034E+0, 1.667E+4, 4.393E+2, 2.871E-3},
// {4.856, 5.460, 18320.0, 438.5, 0.002542}, //Ziegler77
{4.844E+0, 5.458E+0, 7.852E+3, 9.758E+2, 2.077E-2}, //ICRU49
{4.307E+0, 4.843E+0, 1.704E+4, 4.878E+2, 2.882E-3},
// Z= 81-90
{4.723E+0, 5.311E+0, 1.722E+4, 5.370E+2, 2.913E-3},
{5.319E+0, 5.982E+0, 1.740E+4, 5.863E+2, 2.871E-3},
{5.956E+0, 6.700E+0, 1.780E+4, 6.770E+2, 2.660E-3},
{6.158E+0, 6.928E+0, 1.777E+4, 5.863E+2, 2.812E-3},
{6.203E+0, 6.979E+0, 1.795E+4, 5.863E+2, 2.776E-3},
{6.181E+0, 6.954E+0, 1.812E+4, 5.863E+2, 2.748E-3},
{6.949E+0, 7.820E+0, 1.830E+4, 5.863E+2, 2.737E-3},
{7.506E+0, 8.448E+0, 1.848E+4, 5.863E+2, 2.727E-3},
{7.648E+0, 8.609E+0, 1.866E+4, 5.863E+2, 2.697E-3},
{7.711E+0, 8.679E+0, 1.883E+4, 5.863E+2, 2.641E-3},
// Z= 91-92
{7.407E+0, 8.336E+0, 1.901E+4, 5.863E+2, 2.603E-3},
{7.290E+0, 8.204E+0, 1.918E+4, 5.863E+2, 2.673E-3}
};
G4double fac = 1.0 ;
// Carbon specific case for E < 40 keV
if ( T < 40.0 && 5 == i) {
fac = sqrt(T/40.0) ;
T = 40.0 ;
// Free electron gas model
} else if ( T < 10.0 ) {
fac = sqrt(T*0.1) ;
T =10.0 ;
}
// Main parametrisation
G4double slow = a[i][1] * pow(T, 0.45) ;
G4double shigh = log( 1.0 + a[i][3]/T + a[i][4]*T ) * a[i][2]/T ;
ionloss = slow*shigh*fac / (slow + shigh) ;
if ( ionloss < 0.0) { ionloss = 0.0; }
return ionloss;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::DEDX(const G4Material* material, G4double kineticEnergy)
{
G4double eloss = 0.0;
const G4int numberOfElements = material->GetNumberOfElements();
const G4double* theAtomicNumDensityVector =
material->GetAtomicNumDensityVector();
// compaund material with parametrisation
G4int iNist = pstar.GetIndex(material);
if( iNist >= 0 && kineticEnergy <= 2.01*MeV) {
return pstar.GetElectronicDEDX(iNist, kineticEnergy)*material->GetDensity();
} else if( HasMaterial(material) ) {
eloss = StoppingPower(material, kineticEnergy)*
material->GetDensity()/amu;
// Pure material ICRU49 paralmeterisation
} else if(1 == numberOfElements) {
G4double z = material->GetZ();
eloss = ElectronicStoppingPower(z, kineticEnergy)
* (material->GetTotNbOfAtomsPerVolume());
// Experimental data exist only for kinetic energy 125 keV
} else if( MolecIsInZiegler1988(material) ) {
// Loop over elements - calculation based on Bragg's rule
G4double eloss125 = 0.0 ;
const G4ElementVector* theElementVector =
material->GetElementVector();
// Loop for the elements in the material
for (G4int i=0; i<numberOfElements; i++) {
const G4Element* element = (*theElementVector)[i] ;
G4double z = element->GetZ() ;
eloss += ElectronicStoppingPower(z,kineticEnergy)
* theAtomicNumDensityVector[i] ;
eloss125 += ElectronicStoppingPower(z,125.0*keV)
* theAtomicNumDensityVector[i] ;
}
// Chemical factor is taken into account
eloss *= ChemicalFactor(kineticEnergy, eloss125) ;
// Brugg's rule calculation
} else {
const G4ElementVector* theElementVector =
material->GetElementVector() ;
// loop for the elements in the material
for (G4int i=0; i<numberOfElements; i++)
{
const G4Element* element = (*theElementVector)[i] ;
eloss += ElectronicStoppingPower(element->GetZ(), kineticEnergy)
* theAtomicNumDensityVector[i];
}
}
return eloss*theZieglerFactor;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4bool G4BraggModel::MolecIsInZiegler1988(const G4Material* material)
{
// The list of molecules from
// J.F.Ziegler and J.M.Manoyan, The stopping of ions in compaunds,
// Nucl. Inst. & Meth. in Phys. Res. B35 (1988) 215-228.
G4String myFormula = G4String(" ") ;
const G4String chFormula = material->GetChemicalFormula() ;
if (myFormula == chFormula ) { return false; }
// There are no evidence for difference of stopping power depended on
// phase of the compound except for water. The stopping power of the
// water in gas phase can be predicted using Bragg's rule.
//
// No chemical factor for water-gas
myFormula = G4String("H_2O") ;
const G4State theState = material->GetState() ;
if( theState == kStateGas && myFormula == chFormula) return false ;
const size_t numberOfMolecula = 53 ;
// The coffecient from Table.4 of Ziegler & Manoyan
const G4double HeEff = 2.8735 ;
static G4String nameOfMol[numberOfMolecula] = {
"H_2O", "C_2H_4O", "C_3H_6O", "C_2H_2", "C_H_3OH",
"C_2H_5OH", "C_3H_7OH", "C_3H_4", "NH_3", "C_14H_10",
"C_6H_6", "C_4H_10", "C_4H_6", "C_4H_8O", "CCl_4",
"CF_4", "C_6H_8", "C_6H_12", "C_6H_10O", "C_6H_10",
"C_8H_16", "C_5H_10", "C_5H_8", "C_3H_6-Cyclopropane","C_2H_4F_2",
"C_2H_2F_2", "C_4H_8O_2", "C_2H_6", "C_2F_6", "C_2H_6O",
"C_3H_6O", "C_4H_10O", "C_2H_4", "C_2H_4O", "C_2H_4S",
"SH_2", "CH_4", "CCLF_3", "CCl_2F_2", "CHCl_2F",
"(CH_3)_2S", "N_2O", "C_5H_10O", "C_8H_6", "(CH_2)_N",
"(C_3H_6)_N","(C_8H_8)_N", "C_3H_8", "C_3H_6-Propylene", "C_3H_6O",
"C_3H_6S", "C_4H_4S", "C_7H_8"
} ;
static G4double expStopping[numberOfMolecula] = {
66.1, 190.4, 258.7, 42.2, 141.5,
210.9, 279.6, 198.8, 31.0, 267.5,
122.8, 311.4, 260.3, 328.9, 391.3,
206.6, 374.0, 422.0, 432.0, 398.0,
554.0, 353.0, 326.0, 74.6, 220.5,
197.4, 362.0, 170.0, 330.5, 211.3,
262.3, 349.6, 51.3, 187.0, 236.9,
121.9, 35.8, 247.0, 292.6, 268.0,
262.3, 49.0, 398.9, 444.0, 22.91,
68.0, 155.0, 84.0, 74.2, 254.7,
306.8, 324.4, 420.0
} ;
static G4double expCharge[numberOfMolecula] = {
HeEff, HeEff, HeEff, 1.0, HeEff,
HeEff, HeEff, HeEff, 1.0, 1.0,
1.0, HeEff, HeEff, HeEff, HeEff,
HeEff, HeEff, HeEff, HeEff, HeEff,
HeEff, HeEff, HeEff, 1.0, HeEff,
HeEff, HeEff, HeEff, HeEff, HeEff,
HeEff, HeEff, 1.0, HeEff, HeEff,
HeEff, 1.0, HeEff, HeEff, HeEff,
HeEff, 1.0, HeEff, HeEff, 1.0,
1.0, 1.0, 1.0, 1.0, HeEff,
HeEff, HeEff, HeEff
} ;
static G4double numberOfAtomsPerMolecula[numberOfMolecula] = {
3.0, 7.0, 10.0, 4.0, 6.0,
9.0, 12.0, 7.0, 4.0, 24.0,
12.0, 14.0, 10.0, 13.0, 5.0,
5.0, 14.0, 18.0, 17.0, 17.0,
24.0, 15.0, 13.0, 9.0, 8.0,
6.0, 14.0, 8.0, 8.0, 9.0,
10.0, 15.0, 6.0, 7.0, 7.0,
3.0, 5.0, 5.0, 5.0, 5.0,
9.0, 3.0, 16.0, 14.0, 3.0,
9.0, 16.0, 11.0, 9.0, 10.0,
10.0, 9.0, 15.0
} ;
// Search for the compaund in the table
for (size_t i=0; i<numberOfMolecula; i++)
{
if(chFormula == nameOfMol[i]) {
G4double exp125 = expStopping[i] *
(material->GetTotNbOfAtomsPerVolume()) /
(expCharge[i] * numberOfAtomsPerMolecula[i]) ;
SetExpStopPower125(exp125);
return true;
}
}
return false;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4BraggModel::ChemicalFactor(G4double kineticEnergy,
G4double eloss125) const
{
// Approximation of Chemical Factor according to
// J.F.Ziegler and J.M.Manoyan, The stopping of ions in compaunds,
// Nucl. Inst. & Meth. in Phys. Res. B35 (1988) 215-228.
G4double gamma = 1.0 + kineticEnergy/proton_mass_c2 ;
G4double gamma25 = 1.0 + 25.0*keV /proton_mass_c2 ;
G4double gamma125 = 1.0 + 125.0*keV/proton_mass_c2 ;
G4double beta = sqrt(1.0 - 1.0/(gamma*gamma)) ;
G4double beta25 = sqrt(1.0 - 1.0/(gamma25*gamma25)) ;
G4double beta125 = sqrt(1.0 - 1.0/(gamma125*gamma125)) ;
G4double factor = 1.0 + (expStopPower125/eloss125 - 1.0) *
(1.0 + exp( 1.48 * ( beta125/beta25 - 7.0 ) ) ) /
(1.0 + exp( 1.48 * ( beta/beta25 - 7.0 ) ) ) ;
return factor ;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
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