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This commit is contained in:
Gabriele Cosmo
2016-06-09 10:49:58 +02:00
parent 96686e0c8f
commit 1d812b78b1
4545 changed files with 24433 additions and 175005 deletions
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source/processes/electromagnetic/muons/src/G4MuPairProductionModel.cc
+234 -375
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@@ -20,8 +20,8 @@
// * statement, and all its terms. *
// ********************************************************************
//
// $Id: G4MuPairProductionModel.cc,v 1.13 2003/10/21 13:30:05 maire Exp $
// GEANT4 tag $Name: geant4-06-00 $
// $Id: G4MuPairProductionModel.cc,v 1.17 2004/03/02 17:45:03 vnivanch Exp $
// GEANT4 tag $Name: geant4-06-01 $
//
// -------------------------------------------------------------------
//
@@ -43,7 +43,9 @@
// 13-02-03 Add model (V.Ivanchenko)
// 06-06-03 Fix in cross section calculation for high energy (V.Ivanchenko)
// 20-10-03 2*xi in ComputeDDMicroscopicCrossSection (R.Kokoulin)
// 8 integration points in ComputeDMicroscopicCrossSection
// 8 integration points in ComputeDMicroscopicCrossSection
// 12-01-04 Take min cut of e- and e+ not its sum (V.Ivanchenko)
// 10-02-04 Update parameterisation using R.Kokoulin model (V.Ivanchenko)
//
// Class Description:
@@ -71,9 +73,11 @@
//
G4double G4MuPairProductionModel::zdat[]={1.,4.,13.,29.,92.};
G4double G4MuPairProductionModel::adat[]={1.01,9.01,26.98,63.55,238.03};
G4double G4MuPairProductionModel::tdat[]={1.e3,1.e4,1.e5,1.e6,1.e7,1.e8,
1.e9,1.e10};
G4double G4MuPairProductionModel::tdat[]={1.e3,1.e4,1.e5,1.e6,1.e7,1.e8,1.e9,1.e10};
G4double G4MuPairProductionModel::xgi[]={ 0.0199,0.1017,0.2372,0.4083,0.5917,0.7628,0.8983,0.9801 };
G4double G4MuPairProductionModel::wgi[]={ 0.0506,0.1112,0.1569,0.1813,0.1813,0.1569,0.1112,0.0506 };
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4MuPairProductionModel::G4MuPairProductionModel(const G4ParticleDefinition*,
@@ -82,23 +86,27 @@ G4MuPairProductionModel::G4MuPairProductionModel(const G4ParticleDefinition*,
minPairEnergy(4.*electron_mass_c2),
highKinEnergy(1000000.*TeV),
lowKinEnergy(minPairEnergy),
lowestKinEnergy(1.*GeV),
factorForCross(4.*fine_structure_const*fine_structure_const
*classic_electr_radius*classic_electr_radius/(3.*pi)),
sqrte(sqrt(exp(1.))),
particleMass(G4MuonPlus::MuonPlus()->GetPDGMass()),
currentZ(0),
particle(G4MuonPlus::MuonPlus()),
nzdat(5),
ntdat(8),
NBIN(1000),
nbiny(1000),
nmaxElements(0),
ymin(-5.),
ymax(0.),
dy((ymax-ymin)/nbiny),
samplingTablesAreFilled(false)
{ }
{}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4MuPairProductionModel::~G4MuPairProductionModel()
{
size_t n = partialSumSigma.size();
if(n > 0) {
for(size_t i=0; i<n; i++) {
delete partialSumSigma[i];
}
}
}
{}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -117,25 +125,9 @@ G4double G4MuPairProductionModel::LowEnergyLimit(const G4ParticleDefinition*)
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4MuPairProductionModel::MinEnergyCut(const G4ParticleDefinition*,
const G4MaterialCutsCouple* couple)
const G4MaterialCutsCouple* )
{
size_t index = couple->GetIndex();
const G4ProductionCutsTable* theCoupleTable =
G4ProductionCutsTable::GetProductionCutsTable();
G4double eCut = (*(theCoupleTable->GetEnergyCutsVector(1)))[index];
G4double pCut = (*(theCoupleTable->GetEnergyCutsVector(2)))[index];
G4double x = 2*electron_mass_c2 + eCut + pCut;
if(x < minPairEnergy) x = minPairEnergy;
//// if (eCut < highKinEnergy && pCut < highKinEnergy) {
//// x += eCut + pCut;
//// } else {
//// x = 0.5*highKinEnergy;
//// }
return x;
return minPairEnergy;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -148,43 +140,27 @@ G4bool G4MuPairProductionModel::IsInCharge(const G4ParticleDefinition* p)
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
void G4MuPairProductionModel::Initialise(const G4ParticleDefinition*,
const G4DataVector& cuts)
const G4DataVector&)
{
const G4ProductionCutsTable* theCoupleTable =
G4ProductionCutsTable::GetProductionCutsTable();
size_t numOfCouples = theCoupleTable->GetTableSize();
G4double fixedEnergy = sqrt(lowKinEnergy*highKinEnergy);
for (size_t ii=0; ii<partialSumSigma.size(); ii++) {
G4DataVector* a=partialSumSigma[ii];
if ( a ) delete a;
}
partialSumSigma.clear();
for (size_t i=0; i<numOfCouples; i++) {
const G4MaterialCutsCouple* couple=theCoupleTable->GetMaterialCutsCouple(i);
const G4Material* material = couple->GetMaterial();
G4DataVector* dv = ComputePartialSumSigma(material, fixedEnergy,
std::min(cuts[i], 0.25*highKinEnergy));
partialSumSigma.push_back(dv);
}
if (!samplingTablesAreFilled) MakeSamplingTables();
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double
G4MuPairProductionModel::ComputeDEDX(const G4MaterialCutsCouple* couple,
const G4ParticleDefinition*,
G4double kineticEnergy, G4double cutEnergy)
G4double G4MuPairProductionModel::ComputeDEDX(const G4MaterialCutsCouple* couple,
const G4ParticleDefinition*,
G4double kineticEnergy,
G4double cutEnergy)
{
G4double dedx = 0.0;
if (minPairEnergy >= cutEnergy) return dedx;
G4double cut = cutEnergy;
if (kineticEnergy <= cutEnergy) cut = kineticEnergy;
if (minPairEnergy >= cutEnergy || kineticEnergy <= lowestKinEnergy) return dedx;
G4double tmax = MaxSecondaryEnergy(particle, kineticEnergy);
G4double cut = std::min(cutEnergy,tmax);
const G4Material* material = couple->GetMaterial();
const G4ElementVector* theElementVector = material->GetElementVector();
const G4double* theAtomicNumDensityVector =
const G4double* theAtomicNumDensityVector =
material->GetAtomicNumDensityVector();
// loop for elements in the material
@@ -199,24 +175,12 @@ G4MuPairProductionModel::ComputeDEDX(const G4MaterialCutsCouple* couple,
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double
G4MuPairProductionModel::ComputMuPairLoss(G4double Z,
G4double tkin, G4double cutEnergy)
G4double G4MuPairProductionModel::ComputMuPairLoss(G4double Z,
G4double tkin, G4double cutEnergy)
{
static const
G4double xgi[] ={ 0.0199,0.1017,0.2372,0.4083,0.5917,0.7628,0.8983,0.9801};
static const
G4double wgi[] ={ 0.0506,0.1112,0.1569,0.1813,0.1813,0.1569,0.1112,0.0506};
static const G4double ak1=6.9;
static const G4double ak2=1.0;
static const G4double sqrte = sqrt(exp(1.));
static const G4double aaa = log(minPairEnergy);
G4double z13 = pow(Z,0.333333333);
SetCurrentElement(Z);
G4double loss = 0.0;
G4double particleMass = (G4MuonPlus::MuonPlus())->GetPDGMass();
G4double tmax = tkin + particleMass*(1.-0.75*sqrte*z13);
G4double tmax = MaxSecondaryEnergy(particle, tkin);
G4double cut = cutEnergy;
if(tmax <= cutEnergy) cut = tmax;
@@ -224,6 +188,9 @@ G4MuPairProductionModel::ComputMuPairLoss(G4double Z,
// calculate the rectricted loss
// numerical integration in log(PairEnergy)
G4double ak1=6.9;
G4double ak2=1.0;
G4double aaa = log(minPairEnergy);
G4double bbb = log(cut);
G4int kkk = (G4int)((bbb-aaa)/ak1+ak2);
if (kkk > 8) kkk = 8;
@@ -253,22 +220,15 @@ G4double G4MuPairProductionModel::ComputeMicroscopicCrossSection(
G4double cut)
{
static const G4double ak1=6.9 ;
static const G4double ak2=1.0 ;
static const G4double sqrte = sqrt(exp(1.));
static const G4double
xgi[]={ 0.0199,0.1017,0.2372,0.4083,0.5917,0.7628,0.8983,0.9801 };
static const G4double
wgi[]={ 0.0506,0.1112,0.1569,0.1813,0.1813,0.1569,0.1112,0.0506 };
G4double z13 = pow(Z,0.333333333);
G4double cross = 0. ;
G4double particleMass = (G4MuonPlus::MuonPlus())->GetPDGMass();
G4double tmax = tkin + particleMass*(1.-0.75*sqrte*z13);
SetCurrentElement(Z);
G4double tmax = MaxSecondaryEnergy(particle, tkin);
if (tmax <= cut) return cross;
G4double ak1=6.9 ;
G4double ak2=1.0 ;
G4double aaa = log(cut);
G4double bbb = log(tmax);
G4int kkk = (G4int)((bbb-aaa)/ak1 + ak2);
@@ -291,56 +251,14 @@ G4double G4MuPairProductionModel::ComputeMicroscopicCrossSection(
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4MuPairProductionModel::ComputeDMicroscopicCrossSection(
G4double tkin,
G4double Z,
G4double pairEnergy)
// Calculates the differential (D) microscopic cross section
// using the cross section formula of R.P. Kokoulin (18/01/98)
// Code modified by R.P. Kokoulin, V.N. Ivanchenko (27/01/04)
{
static const G4double
xgi[] ={ 0.0199,0.1017,0.2372,0.4083,0.5917,0.7628,0.8983,0.9801 };
static const G4double
wgi[] ={ 0.0506,0.1112,0.1569,0.1813,0.1813,0.1569,0.1112,0.0506 };
G4double cross = 0.;
G4double particleMass = (G4MuonPlus::MuonPlus())->GetPDGMass();
G4double totalEnergy = tkin + particleMass;
G4double energyLoss = totalEnergy - pairEnergy;
G4double a = 6.*particleMass*particleMass/(totalEnergy*energyLoss) ;
G4double b = 4.*electron_mass_c2/pairEnergy;
G4double tmn = (b+2.*a*(1.-b))/(1.+(1.-a)*sqrt(1.-b));
if(tmn <= 0.) return cross;
tmn = log(tmn);
// Gaussian integration in ln(1-ro) ( with 8 points)
for (G4int i=0; i<8; i++)
{
G4double ro = 1.-exp(tmn*xgi[i]);
cross += wgi[i]*(1.-ro)*ComputeDDMicroscopicCrossSection(
tkin,Z,pairEnergy,ro);
}
cross *= -tmn;
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4MuPairProductionModel::ComputeDDMicroscopicCrossSection(
G4double tkin,
G4double Z,
G4double pairEnergy,
G4double asymmetry)
// Calculates the differential (D) microscopic cross section
// using the cross section formula of R.P. Kokoulin (18/01/98)
{
static const G4double sqrte = sqrt(exp(1.)) ;
G4double bbbtf= 183. ;
G4double bbbh = 202.4 ;
G4double g1tf = 1.95e-5 ;
@@ -348,115 +266,111 @@ G4double G4MuPairProductionModel::ComputeDDMicroscopicCrossSection(
G4double g1h = 4.4e-5 ;
G4double g2h = 4.8e-5 ;
G4double particleMass = (G4MuonPlus::MuonPlus())->GetPDGMass();
G4double totalEnergy = tkin + particleMass;
G4double energyLoss = totalEnergy - pairEnergy;
G4double residEnergy = totalEnergy - pairEnergy;
G4double massratio = particleMass/electron_mass_c2 ;
G4double massratio2 = massratio*massratio ;
G4double cross = 0.;
G4double z13 = pow(Z,0.333333333);
G4double z23 = z13*z13 ;
SetCurrentElement(Z);
G4double c3 = 3.*sqrte*particleMass/4. ;
G4double DDCrossSection = 0. ;
if (energyLoss <= c3*z13) return DDCrossSection;
G4double c3 = 0.75*sqrte*particleMass;
if (residEnergy <= c3*z13) return cross;
G4double c7 = 4.*electron_mass_c2;
G4double c8 = 6.*particleMass*particleMass;
G4double alf = c7/pairEnergy;
G4double a3 = 1. - alf;
if (a3 <= 0.) return DDCrossSection;
if (a3 <= 0.) return cross;
// zeta calculation
G4double bbb,g1,g2,zeta1,zeta2,zeta,z2;
G4double bbb,g1,g2;
if( Z < 1.5 ) { bbb = bbbh ; g1 = g1h ; g2 = g2h ; }
else { bbb = bbbtf; g1 = g1tf; g2 = g2tf; }
zeta1 = 0.073 * log(totalEnergy/(particleMass+g1*z23*totalEnergy))-0.26 ;
G4double zeta = 0;
G4double zeta1 = 0.073 * log(totalEnergy/(particleMass+g1*z23*totalEnergy))-0.26 ;
if ( zeta1 > 0.)
{
zeta2 = 0.058*log(totalEnergy/(particleMass+g2*z13*totalEnergy))-0.14 ;
G4double zeta2 = 0.058*log(totalEnergy/(particleMass+g2*z13*totalEnergy))-0.14 ;
zeta = zeta1/zeta2 ;
}
else
{
zeta = 0. ;
}
z2 = Z*(Z+zeta);
G4double z2 = Z*(Z+zeta);
G4double screen0 = 2.*electron_mass_c2*sqrte*bbb/(z13*pairEnergy);
G4double a0 = totalEnergy*energyLoss;
G4double a0 = totalEnergy*residEnergy;
G4double a1 = pairEnergy*pairEnergy/a0;
G4double bet = 0.5*a1;
G4double xi0 = 0.25*massratio2*a1;
G4double del = c8/a0;
G4double romin = 0. ;
G4double romax = (1.-del)*sqrt(1.-c7/pairEnergy);
G4double tmnexp = (alf+2.*del*a3)/(1.+(1.-del)*sqrt(a3));
if(tmnexp <= 0.) return cross;
G4double tmn = log(tmnexp);
G4double sum = 0.;
if((asymmetry < romin) || (asymmetry > romax)) return DDCrossSection;
G4double a4 = 1.-asymmetry ;
G4double a5 = a4*(2.-a4) ;
G4double a6 = 1.-a5 ;
G4double a7 = 1.+a6 ;
G4double a9 = 3.+a6 ;
G4double xi = xi0*a5 ;
G4double xii = 1./xi ;
G4double xi1 = 1.+xi ;
G4double screen = screen0*xi1/a5 ;
G4double yeu = 5.-a6+4.*bet*a7 ;
G4double yed = 2.*(1.+3.*bet)*log(3.+xii)-a6-a1*(2.-a6) ;
G4double yel = 1.+yeu/yed ;
G4double ale=log(bbb/z13*sqrt(xi1*yel)/(1.+screen*yel)) ;
G4double cre = 0.5*log(1.+2.25/(massratio2*z23)*xi1*yel) ;
G4double be;
if (xi <= 1.e3) be = ((2.+a6)*(1.+bet)+xi*a9)*log(1.+xii)+(a5-bet)/xi1-a9;
else be = (3.-a6+a1*a7)/(2*xi);
G4double fe = (ale-cre)*be;
if ( fe < 0.) fe = 0. ;
G4double ymu = 4.+a6 +3.*bet*a7 ;
G4double ymd = a7*(1.5+a1)*log(3.+xi)+1.-1.5*a6 ;
G4double ym1 = 1.+ymu/ymd ;
G4double alm_crm = log(bbb*massratio/(1.5*z23*(1.+screen*ym1)));
G4double a10,bm;
if ( xi >= 1.e-3)
// Gaussian integration in ln(1-ro) ( with 8 points)
for (G4int i=0; i<8; i++)
{
a10 = (1.+a1)*a5 ;
bm = (a7*(1.+1.5*bet)-a10*xii)*log(xi1)+xi*(a5-bet)/xi1+a10;
G4double a4 = exp(tmn*xgi[i]); // a4 = (1.-asymmetry)
G4double a5 = a4*(2.-a4) ;
G4double a6 = 1.-a5 ;
G4double a7 = 1.+a6 ;
G4double a9 = 3.+a6 ;
G4double xi = xi0*a5 ;
G4double xii = 1./xi ;
G4double xi1 = 1.+xi ;
G4double screen = screen0*xi1/a5 ;
G4double yeu = 5.-a6+4.*bet*a7 ;
G4double yed = 2.*(1.+3.*bet)*log(3.+xii)-a6-a1*(2.-a6) ;
G4double ye1 = 1.+yeu/yed ;
G4double ale=log(bbb/z13*sqrt(xi1*ye1)/(1.+screen*ye1)) ;
G4double cre = 0.5*log(1.+2.25*z23*xi1*ye1/massratio2) ;
G4double be;
if (xi <= 1.e3) be = ((2.+a6)*(1.+bet)+xi*a9)*log(1.+xii)+(a5-bet)/xi1-a9;
else be = (3.-a6+a1*a7)/(2.*xi);
G4double fe = (ale-cre)*be;
if ( fe < 0.) fe = 0. ;
G4double ymu = 4.+a6 +3.*bet*a7 ;
G4double ymd = a7*(1.5+a1)*log(3.+xi)+1.-1.5*a6 ;
G4double ym1 = 1.+ymu/ymd ;
G4double alm_crm = log(bbb*massratio/(1.5*z23*(1.+screen*ym1)));
G4double a10,bm;
if ( xi >= 1.e-3)
{
a10 = (1.+a1)*a5 ;
bm = (a7*(1.+1.5*bet)-a10*xii)*log(xi1)+xi*(a5-bet)/xi1+a10;
} else {
bm = (5.-a6+bet*a9)*(xi/2.);
}
G4double fm = alm_crm*bm;
if ( fm < 0.) fm = 0. ;
sum += wgi[i]*a4*(fe+fm/massratio2);
}
else
bm = (5.-a6+bet*a9)*(xi/2.);
G4double fm = alm_crm*bm;
if ( fm < 0.) fm = 0. ;
DDCrossSection = (fe+fm/massratio2);
DDCrossSection *= 4.*fine_structure_const*fine_structure_const
*classic_electr_radius*classic_electr_radius/(3.*pi);
DDCrossSection *= z2*energyLoss/(totalEnergy*pairEnergy);
return DDCrossSection;
cross = -tmn*sum*factorForCross*z2*residEnergy/(totalEnergy*pairEnergy);
return cross;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double
G4MuPairProductionModel::CrossSection(const G4MaterialCutsCouple* couple,
const G4ParticleDefinition*,
G4double kineticEnergy,
G4double cutEnergy, G4double maxEnergy)
G4double G4MuPairProductionModel::CrossSection(const G4MaterialCutsCouple* couple,
const G4ParticleDefinition*,
G4double kineticEnergy,
G4double cutEnergy,
G4double maxEnergy)
{
G4double cross = 0.0;
G4double tmax = std::min(maxEnergy, MaxSecondaryEnergy(particle, kineticEnergy));
G4double cut = std::max(cutEnergy, minPairEnergy);
G4double tmax = std::min(maxEnergy, kineticEnergy);
if (cutEnergy >= tmax) return cross;
if (cut >= tmax || kineticEnergy <= lowestKinEnergy) return cross;
const G4Material* material = couple->GetMaterial();
const G4ElementVector* theElementVector = material->GetElementVector();
@@ -464,11 +378,9 @@ G4MuPairProductionModel::CrossSection(const G4MaterialCutsCouple* couple,
for (size_t i=0; i<material->GetNumberOfElements(); i++) {
G4double Z = (*theElementVector)[i]->GetZ();
G4double cr = ComputeMicroscopicCrossSection(kineticEnergy, Z, cutEnergy);
G4double cr = ComputeMicroscopicCrossSection(kineticEnergy, Z, cut)
- ComputeMicroscopicCrossSection(kineticEnergy, Z, tmax);
if (maxEnergy < kineticEnergy) {
cr -= ComputeMicroscopicCrossSection(kineticEnergy, Z, maxEnergy);
}
cross += theAtomNumDensityVector[i] * cr;
}
return cross;
@@ -476,94 +388,46 @@ G4MuPairProductionModel::CrossSection(const G4MaterialCutsCouple* couple,
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4DataVector* G4MuPairProductionModel::ComputePartialSumSigma(
const G4Material* material,
G4double kineticEnergy,
G4double cut)
// Build the table of cross section per element.
// This table is used by DoIt to select randomly an element in the material.
{
G4int nElements = material->GetNumberOfElements();
const G4ElementVector* theElementVector = material->GetElementVector();
const G4double* theAtomNumDensityVector=material->GetAtomicNumDensityVector();
G4DataVector* dv = new G4DataVector();
G4double cross = 0.0;
for (G4int i=0; i<nElements; i++ ) {
G4double Z = (*theElementVector)[i]->GetZ();
cross += theAtomNumDensityVector[i] * ComputeMicroscopicCrossSection(
kineticEnergy, Z, cut);
dv->push_back(cross);
}
return dv;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
void G4MuPairProductionModel::MakeSamplingTables()
{
static const G4double sqrte = sqrt(exp(1.)) ;
G4double particleMass = (G4MuonPlus::MuonPlus())->GetPDGMass();
for (G4int iz=0; iz<nzdat; iz++)
{
G4double atomicNumber = zdat[iz];
G4double z13 = exp(log(atomicNumber)/3.) ;
G4double Z = zdat[iz];
SetCurrentElement(Z);
for (G4int it=0; it<ntdat; it++)
{
G4double kineticEnergy = tdat[it];
G4double maxPairEnergy = kineticEnergy+particleMass*(1.-0.75*sqrte*z13) ;
G4double maxPairEnergy = MaxSecondaryEnergy(particle,kineticEnergy);
G4double CrossSection = 0.0 ;
G4double ymin = -5. ;
G4double ymax = 0. ;
G4double dy = (ymax-ymin)/NBIN ;
G4double y = ymin - 0.5*dy ;
G4double yy = ymin - dy ;
G4double x = exp(y);
G4double fac = exp(dy);
G4double dx = exp(yy)*(fac - 1.0);
if (maxPairEnergy > minPairEnergy) {
G4double c = log(maxPairEnergy/minPairEnergy);
for (G4int i=0 ; i<NBIN; i++)
{
y += dy ;
x *= fac;
G4double c = log(maxPairEnergy/minPairEnergy);
for (G4int i=0 ; i<nbiny; i++)
{
y += dy ;
if(c > 0.0) {
x *= fac;
dx*= fac;
G4double ep = minPairEnergy*exp(c*x) ;
CrossSection += ep*dx*ComputeDMicroscopicCrossSection(
kineticEnergy, atomicNumber, ep);
ya[i] = y;
proba[iz][it][i] = CrossSection;
kineticEnergy, Z, ep);
}
} else {
for (G4int i=0 ; i<NBIN; i++)
{
y += dy ;
ya[i] = y ;
proba[iz][it][i] = 0.0 ;
}
ya[i] = y;
proba[iz][it][i] = CrossSection;
}
ya[NBIN]=0. ;
ya[nbiny]=ymax;
proba[iz][it][NBIN] = CrossSection;
proba[iz][it][nbiny] = CrossSection;
if(CrossSection > 0.)
{
for(G4int ib=0; ib<=NBIN; ib++)
{
proba[iz][it][ib] /= CrossSection ;
}
}
}
}
samplingTablesAreFilled = true;
@@ -585,129 +449,104 @@ G4DynamicParticle* G4MuPairProductionModel::SampleSecondary(
std::vector<G4DynamicParticle*>* G4MuPairProductionModel::SampleSecondaries(
const G4MaterialCutsCouple* couple,
const G4DynamicParticle* aDynamicParticle,
G4double minEnergy,
G4double maxEnergy)
G4double cut,
G4double tmax)
{
static const G4double esq = sqrt(exp(1.));
G4double kineticEnergy = aDynamicParticle->GetKineticEnergy();
G4double particleMass = aDynamicParticle->GetDefinition()->GetPDGMass();
G4ParticleMomentum ParticleDirection =
aDynamicParticle->GetMomentumDirection();
G4double kineticEnergy = aDynamicParticle->GetKineticEnergy();
G4double totalEnergy = kineticEnergy + particleMass ;
G4ParticleMomentum ParticleDirection = aDynamicParticle->GetMomentumDirection();
// select randomly one element constituing the material
const G4Element* anElement = SelectRandomAtom(couple);
G4int it;
for(it=1; it<ntdat; it++) {if(kineticEnergy <= tdat[it]) break;}
if(it == ntdat) it--;
G4double dt = log(kineticEnergy/tdat[it-1])/log(tdat[it]/tdat[it-1]);
// limits of the energy sampling
G4double totalEnergy = kineticEnergy + particleMass ;
//G4double TotalMomentum = sqrt(KineticEnergy*(TotalEnergy+particleMass)) ;
G4double Z3 = anElement->GetIonisation()->GetZ3() ;
G4double maxPairEnergy = totalEnergy-0.75*esq*particleMass*Z3 ;
if(maxPairEnergy > maxEnergy) maxPairEnergy = maxEnergy;
G4double maxPairEnergy = MaxSecondaryEnergy(particle,kineticEnergy);
G4double maxEnergy = std::min(tmax, maxPairEnergy);
G4double minEnergy = std::min(maxEnergy, cut);
// check against insufficient energy
if(minEnergy >= maxPairEnergy) return 0;
// sample e-e+ energy, pair energy first
G4double PairEnergy,x,yc,y ;
// G4int iZ,iT;
G4int iy ;
// select sampling table ;
G4double lnZ = log(anElement->GetZ()) ;
G4double delmin = 1.e10 ;
G4double del ;
G4int izz = 0;
G4int itt = 0;
G4int NBINminus1 = NBIN-1;
for (G4int iz=0; iz<nzdat; iz++)
{
del = abs(lnZ-log(zdat[iz])) ;
if(del<delmin)
{
delmin=del ;
izz=iz ;
}
}
delmin = 1.e10 ;
for (G4int it=0; it<ntdat; it++)
{
del = abs(log(kineticEnergy)-log(tdat[it])) ;
if(del<delmin)
{
delmin=del;
itt=it ;
}
}
if( minEnergy <= minPairEnergy)
iy = 0 ;
else
{
G4int iymin = 0;
G4int iymax = nbiny;
if( minEnergy > minPairEnergy)
{
G4double xc = log(minEnergy/minPairEnergy)/log(maxPairEnergy/minPairEnergy);
yc = log(xc) ;
iy = -1 ;
do { iy += 1;} while ((ya[iy] < yc )&&(iy < NBINminus1));
}
iymin = (G4int)((log(xc) - ymin)/dy);
xc = log(maxEnergy/minPairEnergy)/log(maxPairEnergy/minPairEnergy);
iymax = (G4int)((log(xc) - ymin)/dy) + 1;
if(iymax > nbiny) iymax = nbiny;
}
G4double norm = proba[izz][itt][iy];
// select randomly one element constituing the material
const G4Element* anElement = SelectRandomAtom(dt, it, iymin, couple);
SetCurrentElement(anElement->GetZ());
G4double r = norm+G4UniformRand()*(1.-norm);
iy -= 1;
do { iy += 1;} while ((proba[izz][itt][iy] < r)&&(iy < NBINminus1));
// sample e-e+ energy, pair energy first
G4int iz, iy;
//sampling is uniformly in y in the bin
if( iy < NBIN ) y = ya[iy] + G4UniformRand() * ( ya[iy+1] - ya[iy]);
else y = ya[iy];
for(iz=1; iz<nzdat; iz++) {if(currentZ <= zdat[iz]) break;}
if(iz == nzdat) iz--;
x = exp(y);
G4double dz = log(currentZ/zdat[iz-1])/log(zdat[iz]/zdat[iz-1]);
PairEnergy = minPairEnergy*exp(x*log(maxPairEnergy/minPairEnergy));
G4double pmin = InterpolatedIntegralCrossSection(dt, dz, iz, it, iymin, currentZ);
G4double pmax = InterpolatedIntegralCrossSection(dt, dz, iz, it, iymax, currentZ);
G4double p = pmin+G4UniformRand()*(pmax - pmin);
// interpolate sampling vector;
G4double p1 = pmin;
G4double p2 = pmin;
for(iy=iymin+1; iy<=iymax; iy++) {
p1 = p2;
p2 = InterpolatedIntegralCrossSection(dt, dz, iz, it, iy, currentZ);
if(p <= p2) break;
}
G4double y = ya[iy-1] + dy*(p - p1)/(p2 - p1);
G4double PairEnergy = minPairEnergy*exp(exp(y)*log(maxPairEnergy/minPairEnergy));
if(PairEnergy < minEnergy) PairEnergy = minEnergy;
if(PairEnergy > maxEnergy) PairEnergy = maxEnergy;
// sample r=(E+-E-)/PairEnergy ( uniformly .....)
G4double rmax = (1.-6.*particleMass*particleMass/(totalEnergy*
G4double rmax = (1.-6.*particleMass*particleMass/(totalEnergy*
(totalEnergy-PairEnergy)))
*sqrt(1.-minPairEnergy/PairEnergy);
r = rmax * (-1.+2.*G4UniformRand()) ;
G4double r = rmax * (-1.+2.*G4UniformRand()) ;
// compute energies from PairEnergy,r
G4double ElectronEnergy=(1.-r)*PairEnergy/2. ;
G4double PositronEnergy=(1.+r)*PairEnergy/2. ;
G4double ElectronEnergy=(1.-r)*PairEnergy/2. ;
G4double PositronEnergy=(1.+r)*PairEnergy/2. ;
// angles of the emitted particles ( Z - axis along the parent particle)
// (mean theta for the moment)
G4double Teta = electron_mass_c2/totalEnergy ;
// angles of the emitted particles ( Z - axis along the parent particle)
// (mean theta for the moment)
G4double Teta = electron_mass_c2/totalEnergy ;
G4double Phi = twopi * G4UniformRand() ;
G4double dirx = sin(Teta)*cos(Phi) , diry = sin(Teta)*sin(Phi) ,
dirz = cos(Teta) ;
G4double Phi = twopi * G4UniformRand() ;
G4double dirx = sin(Teta)*cos(Phi);
G4double diry = sin(Teta)*sin(Phi);
G4double dirz = cos(Teta) ;
G4double ElectronMomentum , PositronMomentum ;
//G4double finalPx,finalPy,finalPz ;
G4double ElectKineEnergy = ElectronEnergy - electron_mass_c2 ;
//G4double finalPx,finalPy,finalPz ;
G4double ElectKineEnergy = ElectronEnergy - electron_mass_c2 ;
ElectronMomentum = sqrt(ElectKineEnergy*(ElectronEnergy+electron_mass_c2));
G4ThreeVector ElectDirection ( dirx, diry, dirz );
ElectDirection.rotateUz(ParticleDirection);
G4ThreeVector ElectDirection ( dirx, diry, dirz );
ElectDirection.rotateUz(ParticleDirection);
// create G4DynamicParticle object for the particle1
G4DynamicParticle* aParticle1= new G4DynamicParticle();
aParticle1->SetDefinition(G4Electron::Electron());
aParticle1->SetMomentumDirection(ElectDirection);
aParticle1->SetKineticEnergy(ElectKineEnergy);
// create G4DynamicParticle object for the particle1
G4DynamicParticle* aParticle1= new G4DynamicParticle(G4Electron::Electron(),
ElectDirection,
ElectKineEnergy);
G4double PositKineEnergy = PositronEnergy - electron_mass_c2 ;
G4double PositKineEnergy = PositronEnergy - electron_mass_c2 ;
PositronMomentum = sqrt(PositKineEnergy*(PositronEnergy+electron_mass_c2));
G4ThreeVector PositDirection ( -dirx, -diry, dirz );
PositDirection.rotateUz(ParticleDirection);
G4ThreeVector PositDirection ( -dirx, -diry, dirz );
PositDirection.rotateUz(ParticleDirection);
// create G4DynamicParticle object for the particle2
G4DynamicParticle* aParticle2= new G4DynamicParticle();
aParticle2->SetDefinition(G4Positron::Positron());
aParticle2->SetMomentumDirection(PositDirection);
aParticle2->SetKineticEnergy(PositKineEnergy);
// create G4DynamicParticle object for the particle2
G4DynamicParticle* aParticle2= new G4DynamicParticle(G4Positron::Positron(),
PositDirection,
PositKineEnergy);
std::vector<G4DynamicParticle*>* vdp = new std::vector<G4DynamicParticle*>;
@@ -719,23 +558,43 @@ std::vector<G4DynamicParticle*>* G4MuPairProductionModel::SampleSecondaries(
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
const G4Element* G4MuPairProductionModel::SelectRandomAtom(
const G4MaterialCutsCouple* couple) const
const G4Element* G4MuPairProductionModel::SelectRandomAtom(G4double dt, G4int it, G4int iy,
const G4MaterialCutsCouple* couple)
{
// select randomly 1 element within the material
const G4Material* material = couple->GetMaterial();
G4int nElements = material->GetNumberOfElements();
size_t nElements = material->GetNumberOfElements();
const G4ElementVector* theElementVector = material->GetElementVector();
if (nElements == 1) return (*theElementVector)[0];
else if (nElements < 1) return 0;
G4DataVector* dv = partialSumSigma[couple->GetIndex()];
G4double rval = G4UniformRand()*((*dv)[nElements-1]);
for (G4int i=0; i<nElements; i++) {
if (rval <= (*dv)[i]) return (*theElementVector)[i];
if(nElements > nmaxElements) {
nmaxElements = nElements;
partialSum.resize(nmaxElements);
}
return (*theElementVector)[nElements-1];
const G4double* theAtomNumDensityVector=material->GetAtomicNumDensityVector();
G4double sum = 0.0;
size_t i;
for (i=0; i<nElements; i++) {
G4double Z = ((*theElementVector)[i])->GetZ();
G4int iz;
for(iz=1; iz<nzdat; iz++) {if(Z <= zdat[iz]) break;}
if(iz == nzdat) iz--;
G4double dz = log(Z/zdat[iz-1])/log(zdat[iz]/zdat[iz-1]);
G4double sigtot = InterpolatedIntegralCrossSection(dt, dz, iz, it, nbiny, Z);
G4double sigcut = InterpolatedIntegralCrossSection(dt, dz, iz, it, iy, Z);
sum += (sigtot - sigcut)*theAtomNumDensityVector[i];
partialSum[i] = sum;
}
G4double rval = G4UniformRand()*sum;
for (i=0; i<nElements; i++) {if(rval<=partialSum[i]) break;}
return (*theElementVector)[i];
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......