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geant4/source/processes/hadronic/models/coherent_elastic/src/G4DiffuseElastic.cc
T
Gabriele Cosmo 286caacf06 Import Geant4 10.0.0 source tree
2016-06-10 11:51:14 +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: G4DiffuseElastic.cc 70682 2013-06-04 07:57:01Z gcosmo $
//
//
// Physics model class G4DiffuseElastic
//
//
// G4 Model: optical diffuse elastic scattering with 4-momentum balance
//
// 24-May-07 V. Grichine
//
#include "G4DiffuseElastic.hh"
#include "G4ParticleTable.hh"
#include "G4ParticleDefinition.hh"
#include "G4IonTable.hh"
#include "G4NucleiProperties.hh"
#include "Randomize.hh"
#include "G4Integrator.hh"
#include "globals.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4Proton.hh"
#include "G4Neutron.hh"
#include "G4Deuteron.hh"
#include "G4Alpha.hh"
#include "G4PionPlus.hh"
#include "G4PionMinus.hh"
#include "G4Element.hh"
#include "G4ElementTable.hh"
#include "G4PhysicsTable.hh"
#include "G4PhysicsLogVector.hh"
#include "G4PhysicsFreeVector.hh"
/////////////////////////////////////////////////////////////////////////
//
// Test Constructor. Just to check xsc
G4DiffuseElastic::G4DiffuseElastic()
: G4HadronElastic("DiffuseElastic"), fParticle(0)
{
SetMinEnergy( 0.01*GeV );
SetMaxEnergy( 1.*TeV );
verboseLevel = 0;
lowEnergyRecoilLimit = 100.*keV;
lowEnergyLimitQ = 0.0*GeV;
lowEnergyLimitHE = 0.0*GeV;
lowestEnergyLimit= 0.0*keV;
plabLowLimit = 20.0*MeV;
theProton = G4Proton::Proton();
theNeutron = G4Neutron::Neutron();
theDeuteron = G4Deuteron::Deuteron();
theAlpha = G4Alpha::Alpha();
thePionPlus = G4PionPlus::PionPlus();
thePionMinus= G4PionMinus::PionMinus();
fEnergyBin = 200;
fAngleBin = 200;
fEnergyVector = new G4PhysicsLogVector( theMinEnergy, theMaxEnergy, fEnergyBin );
fAngleTable = 0;
fParticle = 0;
fWaveVector = 0.;
fAtomicWeight = 0.;
fAtomicNumber = 0.;
fNuclearRadius = 0.;
fBeta = 0.;
fZommerfeld = 0.;
fAm = 0.;
fAddCoulomb = false;
}
//////////////////////////////////////////////////////////////////////////////
//
// Destructor
G4DiffuseElastic::~G4DiffuseElastic()
{
if(fEnergyVector) delete fEnergyVector;
if( fAngleTable )
{
fAngleTable->clearAndDestroy();
delete fAngleTable ;
}
}
//////////////////////////////////////////////////////////////////////////////
//
// Initialisation for given particle using element table of application
void G4DiffuseElastic::Initialise()
{
// fEnergyVector = new G4PhysicsLogVector( theMinEnergy, theMaxEnergy, fEnergyBin );
const G4ElementTable* theElementTable = G4Element::GetElementTable();
size_t jEl, numOfEl = G4Element::GetNumberOfElements();
for(jEl = 0 ; jEl < numOfEl; ++jEl) // application element loop
{
fAtomicNumber = (*theElementTable)[jEl]->GetZ(); // atomic number
fAtomicWeight = (*theElementTable)[jEl]->GetN(); // number of nucleons
fNuclearRadius = CalculateNuclearRad(fAtomicWeight);
if(verboseLevel > 0)
{
G4cout<<"G4DiffuseElastic::Initialise() the element: "
<<(*theElementTable)[jEl]->GetName()<<G4endl;
}
fElementNumberVector.push_back(fAtomicNumber);
fElementNameVector.push_back((*theElementTable)[jEl]->GetName());
BuildAngleTable();
fAngleBank.push_back(fAngleTable);
}
return;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic cross section d(sigma)/d(omega)
G4double
G4DiffuseElastic::GetDiffuseElasticXsc( const G4ParticleDefinition* particle,
G4double theta,
G4double momentum,
G4double A )
{
fParticle = particle;
fWaveVector = momentum/hbarc;
fAtomicWeight = A;
fAddCoulomb = false;
fNuclearRadius = CalculateNuclearRad(A);
G4double sigma = fNuclearRadius*fNuclearRadius*GetDiffElasticProb(theta);
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return invariant differential elastic cross section d(sigma)/d(tMand)
G4double
G4DiffuseElastic::GetInvElasticXsc( const G4ParticleDefinition* particle,
G4double tMand,
G4double plab,
G4double A, G4double Z )
{
G4double m1 = particle->GetPDGMass();
G4LorentzVector lv1(0.,0.,plab,std::sqrt(plab*plab+m1*m1));
G4int iZ = static_cast<G4int>(Z+0.5);
G4int iA = static_cast<G4int>(A+0.5);
G4ParticleDefinition * theDef = 0;
if (iZ == 1 && iA == 1) theDef = theProton;
else if (iZ == 1 && iA == 2) theDef = theDeuteron;
else if (iZ == 1 && iA == 3) theDef = G4Triton::Triton();
else if (iZ == 2 && iA == 3) theDef = G4He3::He3();
else if (iZ == 2 && iA == 4) theDef = theAlpha;
else theDef = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIon(iZ,iA,0);
G4double tmass = theDef->GetPDGMass();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double ptot = p1.mag();
G4double ptot2 = ptot*ptot;
G4double cost = 1 - 0.5*std::fabs(tMand)/ptot2;
if( cost >= 1.0 ) cost = 1.0;
else if( cost <= -1.0) cost = -1.0;
G4double thetaCMS = std::acos(cost);
G4double sigma = GetDiffuseElasticXsc( particle, thetaCMS, ptot, A);
sigma *= pi/ptot2;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic cross section d(sigma)/d(omega) with Coulomb
// correction
G4double
G4DiffuseElastic::GetDiffuseElasticSumXsc( const G4ParticleDefinition* particle,
G4double theta,
G4double momentum,
G4double A, G4double Z )
{
fParticle = particle;
fWaveVector = momentum/hbarc;
fAtomicWeight = A;
fAtomicNumber = Z;
fNuclearRadius = CalculateNuclearRad(A);
fAddCoulomb = false;
G4double z = particle->GetPDGCharge();
G4double kRt = fWaveVector*fNuclearRadius*theta;
G4double kRtC = 1.9;
if( z && (kRt > kRtC) )
{
fAddCoulomb = true;
fBeta = CalculateParticleBeta( particle, momentum);
fZommerfeld = CalculateZommerfeld( fBeta, z, fAtomicNumber);
fAm = CalculateAm( momentum, fZommerfeld, fAtomicNumber);
}
G4double sigma = fNuclearRadius*fNuclearRadius*GetDiffElasticSumProb(theta);
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return invariant differential elastic cross section d(sigma)/d(tMand) with Coulomb
// correction
G4double
G4DiffuseElastic::GetInvElasticSumXsc( const G4ParticleDefinition* particle,
G4double tMand,
G4double plab,
G4double A, G4double Z )
{
G4double m1 = particle->GetPDGMass();
G4LorentzVector lv1(0.,0.,plab,std::sqrt(plab*plab+m1*m1));
G4int iZ = static_cast<G4int>(Z+0.5);
G4int iA = static_cast<G4int>(A+0.5);
G4ParticleDefinition* theDef = 0;
if (iZ == 1 && iA == 1) theDef = theProton;
else if (iZ == 1 && iA == 2) theDef = theDeuteron;
else if (iZ == 1 && iA == 3) theDef = G4Triton::Triton();
else if (iZ == 2 && iA == 3) theDef = G4He3::He3();
else if (iZ == 2 && iA == 4) theDef = theAlpha;
else theDef = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIon(iZ,iA,0);
G4double tmass = theDef->GetPDGMass();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double ptot = p1.mag();
G4double ptot2 = ptot*ptot;
G4double cost = 1 - 0.5*std::fabs(tMand)/ptot2;
if( cost >= 1.0 ) cost = 1.0;
else if( cost <= -1.0) cost = -1.0;
G4double thetaCMS = std::acos(cost);
G4double sigma = GetDiffuseElasticSumXsc( particle, thetaCMS, ptot, A, Z );
sigma *= pi/ptot2;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return invariant differential elastic cross section d(sigma)/d(tMand) with Coulomb
// correction
G4double
G4DiffuseElastic::GetInvCoulombElasticXsc( const G4ParticleDefinition* particle,
G4double tMand,
G4double plab,
G4double A, G4double Z )
{
G4double m1 = particle->GetPDGMass();
G4LorentzVector lv1(0.,0.,plab,std::sqrt(plab*plab+m1*m1));
G4int iZ = static_cast<G4int>(Z+0.5);
G4int iA = static_cast<G4int>(A+0.5);
G4ParticleDefinition * theDef = 0;
if (iZ == 1 && iA == 1) theDef = theProton;
else if (iZ == 1 && iA == 2) theDef = theDeuteron;
else if (iZ == 1 && iA == 3) theDef = G4Triton::Triton();
else if (iZ == 2 && iA == 3) theDef = G4He3::He3();
else if (iZ == 2 && iA == 4) theDef = theAlpha;
else theDef = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIon(iZ,iA,0);
G4double tmass = theDef->GetPDGMass();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double ptot = p1.mag();
G4double ptot2 = ptot*ptot;
G4double cost = 1 - 0.5*std::fabs(tMand)/ptot2;
if( cost >= 1.0 ) cost = 1.0;
else if( cost <= -1.0) cost = -1.0;
G4double thetaCMS = std::acos(cost);
G4double sigma = GetCoulombElasticXsc( particle, thetaCMS, ptot, Z );
sigma *= pi/ptot2;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic probability d(probability)/d(omega)
G4double
G4DiffuseElastic::GetDiffElasticProb( // G4ParticleDefinition* particle,
G4double theta
// G4double momentum,
// G4double A
)
{
G4double sigma, bzero, bzero2, bonebyarg, bonebyarg2, damp, damp2;
G4double delta, diffuse, gamma;
G4double e1, e2, bone, bone2;
// G4double wavek = momentum/hbarc; // wave vector
// G4double r0 = 1.08*fermi;
// G4double rad = r0*std::pow(A, 1./3.);
G4double kr = fWaveVector*fNuclearRadius; // wavek*rad;
G4double kr2 = kr*kr;
G4double krt = kr*theta;
bzero = BesselJzero(krt);
bzero2 = bzero*bzero;
bone = BesselJone(krt);
bone2 = bone*bone;
bonebyarg = BesselOneByArg(krt);
bonebyarg2 = bonebyarg*bonebyarg;
if (fParticle == theProton)
{
diffuse = 0.63*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
else // as proton, if were not defined
{
diffuse = 0.63*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
G4double lambda = 15.; // 15 ok
// G4double kgamma = fWaveVector*gamma; // wavek*delta;
G4double kgamma = lambda*(1.-std::exp(-fWaveVector*gamma/lambda)); // wavek*delta;
G4double kgamma2 = kgamma*kgamma;
// G4double dk2t = delta*fWaveVector*fWaveVector*theta; // delta*wavek*wavek*theta;
// G4double dk2t2 = dk2t*dk2t;
// G4double pikdt = pi*fWaveVector*diffuse*theta;// pi*wavek*diffuse*theta;
G4double pikdt = lambda*(1.-std::exp(-pi*fWaveVector*diffuse*theta/lambda)); // wavek*delta;
damp = DampFactor(pikdt);
damp2 = damp*damp;
G4double mode2k2 = (e1*e1+e2*e2)*fWaveVector*fWaveVector;
G4double e2dk3t = -2.*e2*delta*fWaveVector*fWaveVector*fWaveVector*theta;
sigma = kgamma2;
// sigma += dk2t2;
sigma *= bzero2;
sigma += mode2k2*bone2 + e2dk3t*bzero*bone;
sigma += kr2*bonebyarg2;
sigma *= damp2; // *rad*rad;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic probability d(probability)/d(omega) with
// Coulomb correction
G4double
G4DiffuseElastic::GetDiffElasticSumProb( // G4ParticleDefinition* particle,
G4double theta
// G4double momentum,
// G4double A
)
{
G4double sigma, bzero, bzero2, bonebyarg, bonebyarg2, damp, damp2;
G4double delta, diffuse, gamma;
G4double e1, e2, bone, bone2;
// G4double wavek = momentum/hbarc; // wave vector
// G4double r0 = 1.08*fermi;
// G4double rad = r0*std::pow(A, 1./3.);
G4double kr = fWaveVector*fNuclearRadius; // wavek*rad;
G4double kr2 = kr*kr;
G4double krt = kr*theta;
bzero = BesselJzero(krt);
bzero2 = bzero*bzero;
bone = BesselJone(krt);
bone2 = bone*bone;
bonebyarg = BesselOneByArg(krt);
bonebyarg2 = bonebyarg*bonebyarg;
if (fParticle == theProton)
{
diffuse = 0.63*fermi;
// diffuse = 0.6*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
else // as proton, if were not defined
{
diffuse = 0.63*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
G4double lambda = 15.; // 15 ok
// G4double kgamma = fWaveVector*gamma; // wavek*delta;
G4double kgamma = lambda*(1.-std::exp(-fWaveVector*gamma/lambda)); // wavek*delta;
// G4cout<<"kgamma = "<<kgamma<<G4endl;
if(fAddCoulomb) // add Coulomb correction
{
G4double sinHalfTheta = std::sin(0.5*theta);
G4double sinHalfTheta2 = sinHalfTheta*sinHalfTheta;
kgamma += 0.5*fZommerfeld/kr/(sinHalfTheta2+fAm); // correction at J0()
// kgamma += 0.65*fZommerfeld/kr/(sinHalfTheta2+fAm); // correction at J0()
}
G4double kgamma2 = kgamma*kgamma;
// G4double dk2t = delta*fWaveVector*fWaveVector*theta; // delta*wavek*wavek*theta;
// G4cout<<"dk2t = "<<dk2t<<G4endl;
// G4double dk2t2 = dk2t*dk2t;
// G4double pikdt = pi*fWaveVector*diffuse*theta;// pi*wavek*diffuse*theta;
G4double pikdt = lambda*(1.-std::exp(-pi*fWaveVector*diffuse*theta/lambda)); // wavek*delta;
// G4cout<<"pikdt = "<<pikdt<<G4endl;
damp = DampFactor(pikdt);
damp2 = damp*damp;
G4double mode2k2 = (e1*e1+e2*e2)*fWaveVector*fWaveVector;
G4double e2dk3t = -2.*e2*delta*fWaveVector*fWaveVector*fWaveVector*theta;
sigma = kgamma2;
// sigma += dk2t2;
sigma *= bzero2;
sigma += mode2k2*bone2;
sigma += e2dk3t*bzero*bone;
// sigma += kr2*(1 + 8.*fZommerfeld*fZommerfeld/kr2)*bonebyarg2; // correction at J1()/()
sigma += kr2*bonebyarg2; // correction at J1()/()
sigma *= damp2; // *rad*rad;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic probability d(probability)/d(t) with
// Coulomb correction
G4double
G4DiffuseElastic::GetDiffElasticSumProbA( G4double alpha )
{
G4double theta;
theta = std::sqrt(alpha);
// theta = std::acos( 1 - alpha/2. );
G4double sigma, bzero, bzero2, bonebyarg, bonebyarg2, damp, damp2;
G4double delta, diffuse, gamma;
G4double e1, e2, bone, bone2;
// G4double wavek = momentum/hbarc; // wave vector
// G4double r0 = 1.08*fermi;
// G4double rad = r0*std::pow(A, 1./3.);
G4double kr = fWaveVector*fNuclearRadius; // wavek*rad;
G4double kr2 = kr*kr;
G4double krt = kr*theta;
bzero = BesselJzero(krt);
bzero2 = bzero*bzero;
bone = BesselJone(krt);
bone2 = bone*bone;
bonebyarg = BesselOneByArg(krt);
bonebyarg2 = bonebyarg*bonebyarg;
if (fParticle == theProton)
{
diffuse = 0.63*fermi;
// diffuse = 0.6*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
else // as proton, if were not defined
{
diffuse = 0.63*fermi;
gamma = 0.3*fermi;
delta = 0.1*fermi*fermi;
e1 = 0.3*fermi;
e2 = 0.35*fermi;
}
G4double lambda = 15.; // 15 ok
// G4double kgamma = fWaveVector*gamma; // wavek*delta;
G4double kgamma = lambda*(1.-std::exp(-fWaveVector*gamma/lambda)); // wavek*delta;
// G4cout<<"kgamma = "<<kgamma<<G4endl;
if(fAddCoulomb) // add Coulomb correction
{
G4double sinHalfTheta = theta*0.5; // std::sin(0.5*theta);
G4double sinHalfTheta2 = sinHalfTheta*sinHalfTheta;
kgamma += 0.5*fZommerfeld/kr/(sinHalfTheta2+fAm); // correction at J0()
// kgamma += 0.65*fZommerfeld/kr/(sinHalfTheta2+fAm); // correction at J0()
}
G4double kgamma2 = kgamma*kgamma;
// G4double dk2t = delta*fWaveVector*fWaveVector*theta; // delta*wavek*wavek*theta;
// G4cout<<"dk2t = "<<dk2t<<G4endl;
// G4double dk2t2 = dk2t*dk2t;
// G4double pikdt = pi*fWaveVector*diffuse*theta;// pi*wavek*diffuse*theta;
G4double pikdt = lambda*(1.-std::exp(-pi*fWaveVector*diffuse*theta/lambda)); // wavek*delta;
// G4cout<<"pikdt = "<<pikdt<<G4endl;
damp = DampFactor(pikdt);
damp2 = damp*damp;
G4double mode2k2 = (e1*e1+e2*e2)*fWaveVector*fWaveVector;
G4double e2dk3t = -2.*e2*delta*fWaveVector*fWaveVector*fWaveVector*theta;
sigma = kgamma2;
// sigma += dk2t2;
sigma *= bzero2;
sigma += mode2k2*bone2;
sigma += e2dk3t*bzero*bone;
// sigma += kr2*(1 + 8.*fZommerfeld*fZommerfeld/kr2)*bonebyarg2; // correction at J1()/()
sigma += kr2*bonebyarg2; // correction at J1()/()
sigma *= damp2; // *rad*rad;
return sigma;
}
////////////////////////////////////////////////////////////////////////////
//
// return differential elastic probability 2*pi*sin(theta)*d(probability)/d(omega)
G4double
G4DiffuseElastic::GetIntegrandFunction( G4double alpha )
{
G4double result;
result = GetDiffElasticSumProbA(alpha);
// result *= 2*pi*std::sin(theta);
return result;
}
////////////////////////////////////////////////////////////////////////////
//
// return integral elastic cross section d(sigma)/d(omega) integrated 0 - theta
G4double
G4DiffuseElastic::IntegralElasticProb( const G4ParticleDefinition* particle,
G4double theta,
G4double momentum,
G4double A )
{
G4double result;
fParticle = particle;
fWaveVector = momentum/hbarc;
fAtomicWeight = A;
fNuclearRadius = CalculateNuclearRad(A);
G4Integrator<G4DiffuseElastic,G4double(G4DiffuseElastic::*)(G4double)> integral;
// result = integral.Legendre10(this,&G4DiffuseElastic::GetIntegrandFunction, 0., theta );
result = integral.Legendre96(this,&G4DiffuseElastic::GetIntegrandFunction, 0., theta );
return result;
}
////////////////////////////////////////////////////////////////////////////
//
// Return inv momentum transfer -t > 0
G4double G4DiffuseElastic::SampleT( const G4ParticleDefinition* aParticle, G4double p, G4double A)
{
G4double theta = SampleThetaCMS( aParticle, p, A); // sample theta in cms
G4double t = 2*p*p*( 1 - std::cos(theta) ); // -t !!!
return t;
}
////////////////////////////////////////////////////////////////////////////
//
// Return scattering angle sampled in cms
G4double
G4DiffuseElastic::SampleThetaCMS(const G4ParticleDefinition* particle,
G4double momentum, G4double A)
{
G4int i, iMax = 100;
G4double norm, result, theta1, theta2, thetaMax, sum = 0.;
fParticle = particle;
fWaveVector = momentum/hbarc;
fAtomicWeight = A;
fNuclearRadius = CalculateNuclearRad(A);
thetaMax = 10.174/fWaveVector/fNuclearRadius;
if (thetaMax > pi) thetaMax = pi;
G4Integrator<G4DiffuseElastic,G4double(G4DiffuseElastic::*)(G4double)> integral;
// result = integral.Legendre10(this,&G4DiffuseElastic::GetIntegrandFunction, 0., theta );
norm = integral.Legendre96(this,&G4DiffuseElastic::GetIntegrandFunction, 0., thetaMax );
norm *= G4UniformRand();
for(i = 1; i <= iMax; i++)
{
theta1 = (i-1)*thetaMax/iMax;
theta2 = i*thetaMax/iMax;
sum += integral.Legendre10(this,&G4DiffuseElastic::GetIntegrandFunction, theta1, theta2);
if ( sum >= norm )
{
result = 0.5*(theta1 + theta2);
break;
}
}
if (i > iMax ) result = 0.5*(theta1 + theta2);
G4double sigma = pi*thetaMax/iMax;
result += G4RandGauss::shoot(0.,sigma);
if(result < 0.) result = 0.;
if(result > thetaMax) result = thetaMax;
return result;
}
/////////////////////////////////////////////////////////////////////////////
///////////////////// Table preparation and reading ////////////////////////
////////////////////////////////////////////////////////////////////////////
//
// Return inv momentum transfer -t > 0 from initialisation table
G4double G4DiffuseElastic::SampleInvariantT( const G4ParticleDefinition* aParticle, G4double p,
G4int Z, G4int A)
{
fParticle = aParticle;
G4double m1 = fParticle->GetPDGMass();
G4double totElab = std::sqrt(m1*m1+p*p);
G4double mass2 = G4NucleiProperties::GetNuclearMass(A, Z);
G4LorentzVector lv1(p,0.0,0.0,totElab);
G4LorentzVector lv(0.0,0.0,0.0,mass2);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double momentumCMS = p1.mag();
G4double t = SampleTableT( aParticle, momentumCMS, G4double(Z), G4double(A) ); // sample theta2 in cms
return t;
}
////////////////////////////////////////////////////////////////////////////
//
// Return inv momentum transfer -t > 0 from initialisation table
G4double G4DiffuseElastic::SampleTableT( const G4ParticleDefinition* aParticle, G4double p,
G4double Z, G4double A)
{
G4double alpha = SampleTableThetaCMS( aParticle, p, Z, A); // sample theta2 in cms
// G4double t = 2*p*p*( 1 - std::cos(std::sqrt(alpha)) ); // -t !!!
G4double t = p*p*alpha; // -t !!!
return t;
}
////////////////////////////////////////////////////////////////////////////
//
// Return scattering angle2 sampled in cms according to precalculated table.
G4double
G4DiffuseElastic::SampleTableThetaCMS(const G4ParticleDefinition* particle,
G4double momentum, G4double Z, G4double A)
{
size_t iElement;
G4int iMomentum, iAngle;
G4double randAngle, position, theta1, theta2, E1, E2, W1, W2, W;
G4double m1 = particle->GetPDGMass();
for(iElement = 0; iElement < fElementNumberVector.size(); iElement++)
{
if( std::fabs(Z - fElementNumberVector[iElement]) < 0.5) break;
}
if ( iElement == fElementNumberVector.size() )
{
InitialiseOnFly(Z,A); // table preparation, if needed
// iElement--;
// G4cout << "G4DiffuseElastic: Element with atomic number " << Z
// << " is not found, return zero angle" << G4endl;
// return 0.; // no table for this element
}
// G4cout<<"iElement = "<<iElement<<G4endl;
fAngleTable = fAngleBank[iElement];
G4double kinE = std::sqrt(momentum*momentum + m1*m1) - m1;
for( iMomentum = 0; iMomentum < fEnergyBin; iMomentum++)
{
if( kinE < fEnergyVector->GetLowEdgeEnergy(iMomentum) ) break;
}
if ( iMomentum >= fEnergyBin ) iMomentum = fEnergyBin-1; // kinE is more then theMaxEnergy
if ( iMomentum < 0 ) iMomentum = 0; // against negative index, kinE < theMinEnergy
// G4cout<<"iMomentum = "<<iMomentum<<G4endl;
if (iMomentum == fEnergyBin -1 || iMomentum == 0 ) // the table edges
{
position = (*(*fAngleTable)(iMomentum))(fAngleBin-2)*G4UniformRand();
// G4cout<<"position = "<<position<<G4endl;
for(iAngle = 0; iAngle < fAngleBin-1; iAngle++)
{
if( position < (*(*fAngleTable)(iMomentum))(iAngle) ) break;
}
if (iAngle >= fAngleBin-1) iAngle = fAngleBin-2;
// G4cout<<"iAngle = "<<iAngle<<G4endl;
randAngle = GetScatteringAngle(iMomentum, iAngle, position);
// G4cout<<"randAngle = "<<randAngle<<G4endl;
}
else // kinE inside between energy table edges
{
// position = (*(*fAngleTable)(iMomentum))(fAngleBin-2)*G4UniformRand();
position = (*(*fAngleTable)(iMomentum))(0)*G4UniformRand();
// G4cout<<"position = "<<position<<G4endl;
for(iAngle = 0; iAngle < fAngleBin-1; iAngle++)
{
// if( position < (*(*fAngleTable)(iMomentum))(iAngle) ) break;
if( position > (*(*fAngleTable)(iMomentum))(iAngle) ) break;
}
if (iAngle >= fAngleBin-1) iAngle = fAngleBin-2;
// G4cout<<"iAngle = "<<iAngle<<G4endl;
theta2 = GetScatteringAngle(iMomentum, iAngle, position);
// G4cout<<"theta2 = "<<theta2<<G4endl;
E2 = fEnergyVector->GetLowEdgeEnergy(iMomentum);
// G4cout<<"E2 = "<<E2<<G4endl;
iMomentum--;
// position = (*(*fAngleTable)(iMomentum))(fAngleBin-2)*G4UniformRand();
// G4cout<<"position = "<<position<<G4endl;
for(iAngle = 0; iAngle < fAngleBin-1; iAngle++)
{
// if( position < (*(*fAngleTable)(iMomentum))(iAngle) ) break;
if( position > (*(*fAngleTable)(iMomentum))(iAngle) ) break;
}
if (iAngle >= fAngleBin-1) iAngle = fAngleBin-2;
theta1 = GetScatteringAngle(iMomentum, iAngle, position);
// G4cout<<"theta1 = "<<theta1<<G4endl;
E1 = fEnergyVector->GetLowEdgeEnergy(iMomentum);
// G4cout<<"E1 = "<<E1<<G4endl;
W = 1.0/(E2 - E1);
W1 = (E2 - kinE)*W;
W2 = (kinE - E1)*W;
randAngle = W1*theta1 + W2*theta2;
// randAngle = theta2;
// G4cout<<"randAngle = "<<randAngle<<G4endl;
}
// G4double angle = randAngle;
// if (randAngle > 0.) randAngle /= 2*pi*std::sin(angle);
return randAngle;
}
//////////////////////////////////////////////////////////////////////////////
//
// Initialisation for given particle on fly using new element number
void G4DiffuseElastic::InitialiseOnFly(G4double Z, G4double A)
{
fAtomicNumber = Z; // atomic number
fAtomicWeight = A; // number of nucleons
fNuclearRadius = CalculateNuclearRad(fAtomicWeight);
if( verboseLevel > 0 )
{
G4cout<<"G4DiffuseElastic::Initialise() the element with Z = "
<<Z<<"; and A = "<<A<<G4endl;
}
fElementNumberVector.push_back(fAtomicNumber);
BuildAngleTable();
fAngleBank.push_back(fAngleTable);
return;
}
///////////////////////////////////////////////////////////////////////////////
//
// Build for given particle and element table of momentum, angle probability.
// For the moment in lab system.
void G4DiffuseElastic::BuildAngleTable()
{
G4int i, j;
G4double partMom, kinE, a = 0., z = fParticle->GetPDGCharge(), m1 = fParticle->GetPDGMass();
G4double alpha1, alpha2, alphaMax, alphaCoulomb, delta = 0., sum = 0.;
G4Integrator<G4DiffuseElastic,G4double(G4DiffuseElastic::*)(G4double)> integral;
fAngleTable = new G4PhysicsTable(fEnergyBin);
for( i = 0; i < fEnergyBin; i++)
{
kinE = fEnergyVector->GetLowEdgeEnergy(i);
partMom = std::sqrt( kinE*(kinE + 2*m1) );
fWaveVector = partMom/hbarc;
G4double kR = fWaveVector*fNuclearRadius;
G4double kR2 = kR*kR;
G4double kRmax = 18.6; // 10.6; 10.6, 18, 10.174; ~ 3 maxima of J1 or 15., 25.
G4double kRcoul = 1.9; // 1.2; 1.4, 2.5; // on the first slope of J1
// G4double kRlim = 1.2;
// G4double kRlim2 = kRlim*kRlim/kR2;
alphaMax = kRmax*kRmax/kR2;
if (alphaMax > 4.) alphaMax = 4.; // vmg05-02-09: was pi2
alphaCoulomb = kRcoul*kRcoul/kR2;
if( z )
{
a = partMom/m1; // beta*gamma for m1
fBeta = a/std::sqrt(1+a*a);
fZommerfeld = CalculateZommerfeld( fBeta, z, fAtomicNumber);
fAm = CalculateAm( partMom, fZommerfeld, fAtomicNumber);
}
G4PhysicsFreeVector* angleVector = new G4PhysicsFreeVector(fAngleBin-1);
// G4PhysicsLogVector* angleBins = new G4PhysicsLogVector( 0.001*alphaMax, alphaMax, fAngleBin );
G4double delth = alphaMax/fAngleBin;
sum = 0.;
// fAddCoulomb = false;
fAddCoulomb = true;
// for(j = 1; j < fAngleBin; j++)
for(j = fAngleBin-1; j >= 1; j--)
{
// alpha1 = angleBins->GetLowEdgeEnergy(j-1);
// alpha2 = angleBins->GetLowEdgeEnergy(j);
// alpha1 = alphaMax*(j-1)/fAngleBin;
// alpha2 = alphaMax*( j )/fAngleBin;
alpha1 = delth*(j-1);
// if(alpha1 < kRlim2) alpha1 = kRlim2;
alpha2 = alpha1 + delth;
// if( ( alpha2 > alphaCoulomb ) && z ) fAddCoulomb = true;
if( ( alpha1 < alphaCoulomb ) && z ) fAddCoulomb = false;
delta = integral.Legendre10(this, &G4DiffuseElastic::GetIntegrandFunction, alpha1, alpha2);
// delta = integral.Legendre96(this, &G4DiffuseElastic::GetIntegrandFunction, alpha1, alpha2);
sum += delta;
angleVector->PutValue( j-1 , alpha1, sum ); // alpha2
// G4cout<<"j-1 = "<<j-1<<"; alpha2 = "<<alpha2<<"; sum = "<<sum<<G4endl;
}
fAngleTable->insertAt(i,angleVector);
// delete[] angleVector;
// delete[] angleBins;
}
return;
}
/////////////////////////////////////////////////////////////////////////////////
//
//
G4double
G4DiffuseElastic:: GetScatteringAngle( G4int iMomentum, G4int iAngle, G4double position )
{
G4double x1, x2, y1, y2, randAngle;
if( iAngle == 0 )
{
randAngle = (*fAngleTable)(iMomentum)->GetLowEdgeEnergy(iAngle);
// iAngle++;
}
else
{
if ( iAngle >= G4int((*fAngleTable)(iMomentum)->GetVectorLength()) )
{
iAngle = (*fAngleTable)(iMomentum)->GetVectorLength() - 1;
}
y1 = (*(*fAngleTable)(iMomentum))(iAngle-1);
y2 = (*(*fAngleTable)(iMomentum))(iAngle);
x1 = (*fAngleTable)(iMomentum)->GetLowEdgeEnergy(iAngle-1);
x2 = (*fAngleTable)(iMomentum)->GetLowEdgeEnergy(iAngle);
if ( x1 == x2 ) randAngle = x2;
else
{
if ( y1 == y2 ) randAngle = x1 + ( x2 - x1 )*G4UniformRand();
else
{
randAngle = x1 + ( position - y1 )*( x2 - x1 )/( y2 - y1 );
}
}
}
return randAngle;
}
////////////////////////////////////////////////////////////////////////////
//
// Return scattering angle sampled in lab system (target at rest)
G4double
G4DiffuseElastic::SampleThetaLab( const G4HadProjectile* aParticle,
G4double tmass, G4double A)
{
const G4ParticleDefinition* theParticle = aParticle->GetDefinition();
G4double m1 = theParticle->GetPDGMass();
G4double plab = aParticle->GetTotalMomentum();
G4LorentzVector lv1 = aParticle->Get4Momentum();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double ptot = p1.mag();
G4double tmax = 4.0*ptot*ptot;
G4double t = 0.0;
//
// Sample t
//
t = SampleT( theParticle, ptot, A);
// NaN finder
if(!(t < 0.0 || t >= 0.0))
{
if (verboseLevel > 0)
{
G4cout << "G4DiffuseElastic:WARNING: A = " << A
<< " mom(GeV)= " << plab/GeV
<< " S-wave will be sampled"
<< G4endl;
}
t = G4UniformRand()*tmax;
}
if(verboseLevel>1)
{
G4cout <<" t= " << t << " tmax= " << tmax
<< " ptot= " << ptot << G4endl;
}
// Sampling of angles in CM system
G4double phi = G4UniformRand()*twopi;
G4double cost = 1. - 2.0*t/tmax;
G4double sint;
if( cost >= 1.0 )
{
cost = 1.0;
sint = 0.0;
}
else if( cost <= -1.0)
{
cost = -1.0;
sint = 0.0;
}
else
{
sint = std::sqrt((1.0-cost)*(1.0+cost));
}
if (verboseLevel>1)
{
G4cout << "cos(t)=" << cost << " std::sin(t)=" << sint << G4endl;
}
G4ThreeVector v1(sint*std::cos(phi),sint*std::sin(phi),cost);
v1 *= ptot;
G4LorentzVector nlv1(v1.x(),v1.y(),v1.z(),std::sqrt(ptot*ptot + m1*m1));
nlv1.boost(bst);
G4ThreeVector np1 = nlv1.vect();
// G4double theta = std::acos( np1.z()/np1.mag() ); // degree;
G4double theta = np1.theta();
return theta;
}
////////////////////////////////////////////////////////////////////////////
//
// Return scattering angle in lab system (target at rest) knowing theta in CMS
G4double
G4DiffuseElastic::ThetaCMStoThetaLab( const G4DynamicParticle* aParticle,
G4double tmass, G4double thetaCMS)
{
const G4ParticleDefinition* theParticle = aParticle->GetDefinition();
G4double m1 = theParticle->GetPDGMass();
// G4double plab = aParticle->GetTotalMomentum();
G4LorentzVector lv1 = aParticle->Get4Momentum();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
lv1.boost(-bst);
G4ThreeVector p1 = lv1.vect();
G4double ptot = p1.mag();
G4double phi = G4UniformRand()*twopi;
G4double cost = std::cos(thetaCMS);
G4double sint;
if( cost >= 1.0 )
{
cost = 1.0;
sint = 0.0;
}
else if( cost <= -1.0)
{
cost = -1.0;
sint = 0.0;
}
else
{
sint = std::sqrt((1.0-cost)*(1.0+cost));
}
if (verboseLevel>1)
{
G4cout << "cos(tcms)=" << cost << " std::sin(tcms)=" << sint << G4endl;
}
G4ThreeVector v1(sint*std::cos(phi),sint*std::sin(phi),cost);
v1 *= ptot;
G4LorentzVector nlv1(v1.x(),v1.y(),v1.z(),std::sqrt(ptot*ptot + m1*m1));
nlv1.boost(bst);
G4ThreeVector np1 = nlv1.vect();
G4double thetaLab = np1.theta();
return thetaLab;
}
////////////////////////////////////////////////////////////////////////////
//
// Return scattering angle in CMS system (target at rest) knowing theta in Lab
G4double
G4DiffuseElastic::ThetaLabToThetaCMS( const G4DynamicParticle* aParticle,
G4double tmass, G4double thetaLab)
{
const G4ParticleDefinition* theParticle = aParticle->GetDefinition();
G4double m1 = theParticle->GetPDGMass();
G4double plab = aParticle->GetTotalMomentum();
G4LorentzVector lv1 = aParticle->Get4Momentum();
G4LorentzVector lv(0.0,0.0,0.0,tmass);
lv += lv1;
G4ThreeVector bst = lv.boostVector();
// lv1.boost(-bst);
// G4ThreeVector p1 = lv1.vect();
// G4double ptot = p1.mag();
G4double phi = G4UniformRand()*twopi;
G4double cost = std::cos(thetaLab);
G4double sint;
if( cost >= 1.0 )
{
cost = 1.0;
sint = 0.0;
}
else if( cost <= -1.0)
{
cost = -1.0;
sint = 0.0;
}
else
{
sint = std::sqrt((1.0-cost)*(1.0+cost));
}
if (verboseLevel>1)
{
G4cout << "cos(tlab)=" << cost << " std::sin(tlab)=" << sint << G4endl;
}
G4ThreeVector v1(sint*std::cos(phi),sint*std::sin(phi),cost);
v1 *= plab;
G4LorentzVector nlv1(v1.x(),v1.y(),v1.z(),std::sqrt(plab*plab + m1*m1));
nlv1.boost(-bst);
G4ThreeVector np1 = nlv1.vect();
G4double thetaCMS = np1.theta();
return thetaCMS;
}
///////////////////////////////////////////////////////////////////////////////
//
// Test for given particle and element table of momentum, angle probability.
// For the moment in lab system.
void G4DiffuseElastic::TestAngleTable(const G4ParticleDefinition* theParticle, G4double partMom,
G4double Z, G4double A)
{
fAtomicNumber = Z; // atomic number
fAtomicWeight = A; // number of nucleons
fNuclearRadius = CalculateNuclearRad(fAtomicWeight);
G4cout<<"G4DiffuseElastic::TestAngleTable() init the element with Z = "
<<Z<<"; and A = "<<A<<G4endl;
fElementNumberVector.push_back(fAtomicNumber);
G4int i=0, j;
G4double a = 0., z = theParticle->GetPDGCharge(), m1 = fParticle->GetPDGMass();
G4double alpha1=0., alpha2=0., alphaMax=0., alphaCoulomb=0.;
G4double deltaL10 = 0., deltaL96 = 0., deltaAG = 0.;
G4double sumL10 = 0.,sumL96 = 0.,sumAG = 0.;
G4double epsilon = 0.001;
G4Integrator<G4DiffuseElastic,G4double(G4DiffuseElastic::*)(G4double)> integral;
fAngleTable = new G4PhysicsTable(fEnergyBin);
fWaveVector = partMom/hbarc;
G4double kR = fWaveVector*fNuclearRadius;
G4double kR2 = kR*kR;
G4double kRmax = 10.6; // 10.6, 18, 10.174; ~ 3 maxima of J1 or 15., 25.
G4double kRcoul = 1.2; // 1.4, 2.5; // on the first slope of J1
alphaMax = kRmax*kRmax/kR2;
if (alphaMax > 4.) alphaMax = 4.; // vmg05-02-09: was pi2
alphaCoulomb = kRcoul*kRcoul/kR2;
if( z )
{
a = partMom/m1; // beta*gamma for m1
fBeta = a/std::sqrt(1+a*a);
fZommerfeld = CalculateZommerfeld( fBeta, z, fAtomicNumber);
fAm = CalculateAm( partMom, fZommerfeld, fAtomicNumber);
}
G4PhysicsFreeVector* angleVector = new G4PhysicsFreeVector(fAngleBin-1);
// G4PhysicsLogVector* angleBins = new G4PhysicsLogVector( 0.001*alphaMax, alphaMax, fAngleBin );
fAddCoulomb = false;
for(j = 1; j < fAngleBin; j++)
{
// alpha1 = angleBins->GetLowEdgeEnergy(j-1);
// alpha2 = angleBins->GetLowEdgeEnergy(j);
alpha1 = alphaMax*(j-1)/fAngleBin;
alpha2 = alphaMax*( j )/fAngleBin;
if( ( alpha2 > alphaCoulomb ) && z ) fAddCoulomb = true;
deltaL10 = integral.Legendre10(this, &G4DiffuseElastic::GetIntegrandFunction, alpha1, alpha2);
deltaL96 = integral.Legendre96(this, &G4DiffuseElastic::GetIntegrandFunction, alpha1, alpha2);
deltaAG = integral.AdaptiveGauss(this, &G4DiffuseElastic::GetIntegrandFunction,
alpha1, alpha2,epsilon);
// G4cout<<alpha1<<"\t"<<std::sqrt(alpha1)/degree<<"\t"
// <<deltaL10<<"\t"<<deltaL96<<"\t"<<deltaAG<<G4endl;
sumL10 += deltaL10;
sumL96 += deltaL96;
sumAG += deltaAG;
G4cout<<alpha1<<"\t"<<std::sqrt(alpha1)/degree<<"\t"
<<sumL10<<"\t"<<sumL96<<"\t"<<sumAG<<G4endl;
angleVector->PutValue( j-1 , alpha1, sumL10 ); // alpha2
}
fAngleTable->insertAt(i,angleVector);
fAngleBank.push_back(fAngleTable);
/*
// Integral over all angle range - Bad accuracy !!!
sumL10 = integral.Legendre10(this, &G4DiffuseElastic::GetIntegrandFunction, 0., alpha2);
sumL96 = integral.Legendre96(this, &G4DiffuseElastic::GetIntegrandFunction, 0., alpha2);
sumAG = integral.AdaptiveGauss(this, &G4DiffuseElastic::GetIntegrandFunction,
0., alpha2,epsilon);
G4cout<<G4endl;
G4cout<<alpha2<<"\t"<<std::sqrt(alpha2)/degree<<"\t"
<<sumL10<<"\t"<<sumL96<<"\t"<<sumAG<<G4endl;
*/
return;
}
//
//
/////////////////////////////////////////////////////////////////////////////////
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