Gabriele Cosmo
113 lines
4.9 KiB
C++
113 lines
4.9 KiB
C++
//
|
|
// ********************************************************************
|
|
// * 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. *
|
|
// ********************************************************************
|
|
//
|
|
|
|
#include "G4AdjointAlongStepWeightCorrection.hh"
|
|
|
|
#include "G4AdjointCSManager.hh"
|
|
#include "G4ParticleChange.hh"
|
|
#include "G4ParticleDefinition.hh"
|
|
#include "G4Step.hh"
|
|
#include "G4VParticleChange.hh"
|
|
|
|
///////////////////////////////////////////////////////
|
|
G4AdjointAlongStepWeightCorrection::G4AdjointAlongStepWeightCorrection(
|
|
const G4String& name, G4ProcessType type)
|
|
: G4VContinuousProcess(name, type)
|
|
{
|
|
fParticleChange = new G4ParticleChange();
|
|
fCSManager = G4AdjointCSManager::GetAdjointCSManager();
|
|
}
|
|
|
|
///////////////////////////////////////////////////////
|
|
G4AdjointAlongStepWeightCorrection::~G4AdjointAlongStepWeightCorrection()
|
|
{
|
|
delete fParticleChange;
|
|
}
|
|
|
|
///////////////////////////////////////////////////////
|
|
void G4AdjointAlongStepWeightCorrection::ProcessDescription(
|
|
std::ostream& out) const
|
|
{
|
|
out <<
|
|
"Continuous processes act on adjoint particles to continuously correct their "
|
|
"weight during the adjoint reverse tracking. This process is needed when "
|
|
"the adjoint cross sections are not scaled such that the total adjoint cross "
|
|
"section matches the total forward cross section. By default the mode where "
|
|
"the total adjoint cross section is equal to the total forward cross section "
|
|
"is used and therefore this along step weightcorrection factor is 1. However "
|
|
"in some cases (some energy ranges) the total forward cross section or the "
|
|
"total adjoint cross section can be zero. In this case the along step weight "
|
|
"correction is needed and is given by exp(-(Sigma_tot_adj-Sigma_tot_fwd).dx)"
|
|
"\n";
|
|
}
|
|
|
|
///////////////////////////////////////////////////////
|
|
G4VParticleChange* G4AdjointAlongStepWeightCorrection::AlongStepDoIt(
|
|
const G4Track& track, const G4Step& step)
|
|
{
|
|
fParticleChange->Initialize(track);
|
|
|
|
// Get the actual (true) Step length
|
|
G4double length = step.GetStepLength();
|
|
|
|
G4double Tkin = step.GetPostStepPoint()->GetKineticEnergy();
|
|
G4ParticleDefinition* thePartDef = const_cast<G4ParticleDefinition*>(
|
|
track.GetDynamicParticle()->GetDefinition());
|
|
G4double weight_correction = fCSManager->GetContinuousWeightCorrection(
|
|
thePartDef, fPreStepKinEnergy, Tkin, fCurrentCouple, length);
|
|
|
|
// Caution!!!
|
|
// It is important to select the weight of the post_step_point as the current
|
|
// weight and not the weight of the track, as the weight of the track is
|
|
// changed after having applied all the along_step_do_it.
|
|
G4double new_weight =
|
|
weight_correction * step.GetPostStepPoint()->GetWeight();
|
|
|
|
// The following test check for zero weight.
|
|
// This happens after weight correction of gamma for photo electric effect.
|
|
// When the new weight is 0 it will be later on considered as NaN by G4.
|
|
// Therefore we put a lower limit of 1.e-300. for new_weight
|
|
if(new_weight == 0. || (new_weight <= 0. && new_weight > 0.))
|
|
{
|
|
new_weight = 1.e-300;
|
|
}
|
|
|
|
fParticleChange->SetParentWeightByProcess(false);
|
|
fParticleChange->SetSecondaryWeightByProcess(false);
|
|
fParticleChange->ProposeParentWeight(new_weight);
|
|
|
|
return fParticleChange;
|
|
}
|
|
|
|
///////////////////////////////////////////////////////
|
|
G4double G4AdjointAlongStepWeightCorrection::GetContinuousStepLimit(
|
|
const G4Track& track, G4double, G4double, G4double&)
|
|
{
|
|
DefineMaterial(track.GetMaterialCutsCouple());
|
|
fPreStepKinEnergy = track.GetKineticEnergy();
|
|
return DBL_MAX;
|
|
}
|