Gabriele Cosmo
186 lines
7.8 KiB
Plaintext
186 lines
7.8 KiB
Plaintext
//
|
|
// ********************************************************************
|
|
// * 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: G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy.icc,v 1.2 2006/06/29 19:34:49 gunter Exp $
|
|
// GEANT4 tag $Name: geant4-08-01 $
|
|
//
|
|
|
|
#ifdef G4DNAMILLERANDGREENEXCITATIONTOTALCROSSSECTIONPOLICY_HH
|
|
#include "Randomize.hh"
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: TotalCrossSection(G4double k, G4int z ) const
|
|
{
|
|
if (k < EnergyLimitsPolicy::lowEnergyLimit)
|
|
{
|
|
if (EnergyLimitsPolicy::zeroBelowLowEnergyLimit)
|
|
return 0;
|
|
|
|
k=EnergyLimitsPolicy::lowEnergyLimit;
|
|
}
|
|
else if (k > EnergyLimitsPolicy::highEnergyLimit)
|
|
{
|
|
if (EnergyLimitsPolicy::zeroAboveHighEnergyLimit)
|
|
return 0;
|
|
|
|
k=EnergyLimitsPolicy::highEnergyLimit;
|
|
}
|
|
|
|
G4int i(5);
|
|
G4double totalCrossSection(0.);
|
|
|
|
while (i>0)
|
|
{
|
|
i--;
|
|
totalCrossSection+=PartialCrossSection(k, z, i);
|
|
}
|
|
|
|
return totalCrossSection;
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4int G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: RandomizePartialCrossSection(G4double k, G4int z) const
|
|
{
|
|
G4int i(5);
|
|
G4double values[5];
|
|
G4double value(0);
|
|
|
|
while (i>0)
|
|
{
|
|
i--;
|
|
values[i]=PartialCrossSection(k, z, i);
|
|
value+=values[i];
|
|
}
|
|
|
|
value*=G4UniformRand();
|
|
|
|
i=5;
|
|
while (i>0)
|
|
{
|
|
i--;
|
|
|
|
if (values[i]>value)
|
|
return i;
|
|
|
|
value-=values[i];
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: EnergyConstant(G4int excitationLevelIndex) const
|
|
{
|
|
const G4double ej[]={8.17*eV, 10.13*eV, 11.31*eV, 12.91*eV, 14.50*eV};
|
|
|
|
return ej[excitationLevelIndex];
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: PartialCrossSection(G4double t, G4int z, G4int excitationLevelIndex) const
|
|
{
|
|
// ( ( z * aj ) ^ omegaj ) * ( t - ej ) ^ nu
|
|
// sigma(t) = zEff^2 * sigma0 * --------------------------------------------
|
|
// jj ^ ( omegaj + nu ) + t ^ ( omegaj + nu )
|
|
//
|
|
// where t is the kinetic energy corrected by Helium mass over proton mass for Helium ions
|
|
//
|
|
// zEff is:
|
|
// 1 for protons
|
|
// 2 for alpha++
|
|
// and 2 - c1 S_1s - c2 S_2s - c3 S_2p for alpha+ and He
|
|
//
|
|
// Dingfelder et al., RPC 59 p. 266 (2000) from Miller and Green (1973)
|
|
|
|
const G4double sigma0(1.E+8 * barn);
|
|
const G4double nu(1.);
|
|
const G4double aj[]={876.*eV, 2084.*eV, 1373.*eV, 692.*eV, 900.*eV};
|
|
const G4double jj[]={19820.*eV, 23490.*eV, 27770.*eV, 30830.*eV, 33080.*eV};
|
|
const G4double omegaj[]={0.85, 0.88, 0.88, 0.78, 0.78};
|
|
|
|
G4double tCorrected;
|
|
tCorrected=t*IncomingParticlePolicy::kineticEnergyCorrection;
|
|
|
|
G4double numerator;
|
|
numerator=std::pow(z*aj[excitationLevelIndex], omegaj[excitationLevelIndex]) * std::pow(tCorrected - EnergyConstant(excitationLevelIndex), nu);
|
|
|
|
G4double power;
|
|
power=omegaj[excitationLevelIndex]+nu;
|
|
|
|
G4double denominator;
|
|
denominator=std::pow(jj[excitationLevelIndex], power) + std::pow(tCorrected, power);
|
|
|
|
G4ParticleDefinition const * particle(IncomingParticlePolicy::IncomingParticleDefinition());
|
|
G4double zEff=particle->GetPDGCharge()/eplus+particle->GetLeptonNumber();
|
|
|
|
zEff-=( IncomingParticlePolicy::sCoefficient[0]*S_1s(t, EnergyConstant(excitationLevelIndex), IncomingParticlePolicy::slaterEffectiveCharge[0], 1.) +
|
|
IncomingParticlePolicy::sCoefficient[1]*S_2s(t, EnergyConstant(excitationLevelIndex), IncomingParticlePolicy::slaterEffectiveCharge[1], 2.) +
|
|
IncomingParticlePolicy::sCoefficient[2]*S_2p(t, EnergyConstant(excitationLevelIndex), IncomingParticlePolicy::slaterEffectiveCharge[2], 2.) );
|
|
|
|
return sigma0 * zEff * zEff * numerator / denominator;
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: S_1s(G4double t, G4double energyTransferred, G4double slaterEffectiveCharge, G4double shellNumber) const
|
|
{
|
|
// 1 - e^(-2r) * ( 1 + 2 r + 2 r^2)
|
|
|
|
G4double r(R(t, energyTransferred, slaterEffectiveCharge, shellNumber));
|
|
|
|
return 1.-std::exp(-2*r) * ( ( 2. * r + 2. ) * r + 1. );
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: S_2s(G4double t, G4double energyTransferred, G4double slaterEffectiveCharge, G4double shellNumber) const
|
|
{
|
|
// 1 - e^(-2 r) * ( 1 + 2 r + 2 r^2 + 2 r^4)
|
|
|
|
G4double r(R(t, energyTransferred, slaterEffectiveCharge, shellNumber));
|
|
|
|
return 1.-std::exp(-2*r) * ( ( ( 2. * r * r + 2. ) * r + 2. ) * r + 1. );
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: S_2p(G4double t, G4double energyTransferred, G4double slaterEffectiveCharge, G4double shellNumber) const
|
|
{
|
|
// 1 - e^(-2 r) * ( 1 + 2 r + 2 r^2 + 4/3 r^3 + 2/3 r^4)
|
|
|
|
G4double r(R(t, energyTransferred, slaterEffectiveCharge, shellNumber));
|
|
|
|
return 1.-std::exp(-2*r) * ( ( ( ( 2./3. * r + 4./3. ) * r + 2. ) * r + 2. ) * r + 1. );
|
|
}
|
|
|
|
template <typename IncomingParticlePolicy, typename EnergyLimitsPolicy>
|
|
G4double G4DNAMillerAndGreenExcitationTotalCrossSectionPolicy<IncomingParticlePolicy, EnergyLimitsPolicy> :: R(G4double t, G4double energyTransferred, G4double slaterEffectiveCharge, G4double shellNumber) const
|
|
{
|
|
// tElectron = m_electron / m_alpha * t
|
|
|
|
G4double tElectron = 0.511/3728 * t;
|
|
|
|
return 2.*tElectron*slaterEffectiveCharge/(energyTransferred*shellNumber);
|
|
}
|
|
#endif /* G4DNAMILLERANDGREENEXCITATIONTOTALCROSSSECTIONPOLICY_HH */
|