Files
geant4/source/processes/electromagnetic/adjoint/include/G4UrbanAdjointMscModel.hh
T
2016-12-09 12:35:28 +01:00

284 lines
8.1 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. *
// ********************************************************************
//
// $Id: $
// GEANT4 tag $Name: $
//
// -------------------------------------------------------------------
//
//
// GEANT4 Class header file
//
//
// File name: G4UrbanAdjointMscModel
//
// Author: Laszlo Urban
//
// Creation date: 19.02.2013
//
// Created from G4UrbanAdjointMscModel96
//
// New parametrization for theta0
// Correction for very small step length
//
// Class Description:
//
// Implementation of the model of multiple scattering based on
// H.W.Lewis Phys Rev 78 (1950) 526 and L.Urban model
// -------------------------------------------------------------------
//
#ifndef G4UrbanAdjointMscModel_h
#define G4UrbanAdjointMscModel_h 1
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include <CLHEP/Units/SystemOfUnits.h>
#include "G4VMscModel.hh"
#include "G4MscStepLimitType.hh"
#include "G4Log.hh"
#include "G4Exp.hh"
#include "G4Electron.hh"
class G4ParticleChangeForMSC;
class G4SafetyHelper;
class G4LossTableManager;
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
class G4UrbanAdjointMscModel : public G4VMscModel
{
public:
explicit G4UrbanAdjointMscModel(const G4String& nam = "UrbanMsc");
virtual ~G4UrbanAdjointMscModel();
virtual void Initialise(const G4ParticleDefinition*,
const G4DataVector&) override;
virtual void StartTracking(G4Track*) override;
virtual G4double
ComputeCrossSectionPerAtom(const G4ParticleDefinition* particle,
G4double KineticEnergy,
G4double AtomicNumber,
G4double AtomicWeight=0.,
G4double cut =0.,
G4double emax=DBL_MAX) override;
virtual G4ThreeVector& SampleScattering(const G4ThreeVector&,
G4double safety) override;
virtual G4double
ComputeTruePathLengthLimit(const G4Track& track,
G4double& currentMinimalStep) override;
virtual G4double ComputeGeomPathLength(G4double truePathLength) override;
virtual G4double ComputeTrueStepLength(G4double geomStepLength) override;
G4double ComputeTheta0(G4double truePathLength, G4double KineticEnergy);
inline void SetNewDisplacementFlag(G4bool);
private:
G4double SampleCosineTheta(G4double trueStepLength, G4double KineticEnergy);
void SampleDisplacement(G4double sinTheta, G4double phi);
void SampleDisplacementNew(G4double sinTheta, G4double phi);
inline void SetParticle(const G4ParticleDefinition*);
inline void UpdateCache();
inline G4double Randomizetlimit();
inline G4double SimpleScattering(G4double xmeanth, G4double x2meanth);
// hide assignment operator
G4UrbanAdjointMscModel & operator=(const G4UrbanAdjointMscModel &right) = delete;
G4UrbanAdjointMscModel(const G4UrbanAdjointMscModel&) = delete;
CLHEP::HepRandomEngine* rndmEngineMod;
const G4ParticleDefinition* particle;
const G4ParticleDefinition* positron;
G4ParticleChangeForMSC* fParticleChange;
const G4MaterialCutsCouple* couple;
G4LossTableManager* theManager;
G4double mass;
G4double charge,ChargeSquare;
G4double masslimite,lambdalimit,fr;
G4double taubig;
G4double tausmall;
G4double taulim;
G4double currentTau;
G4double tlimit;
G4double tlimitmin;
G4double tlimitminfix,tlimitminfix2;
G4double tgeom;
G4double geombig;
G4double geommin;
G4double geomlimit;
G4double skindepth;
G4double smallstep;
G4double presafety;
G4double lambda0;
G4double lambdaeff;
G4double tPathLength;
G4double zPathLength;
G4double par1,par2,par3;
G4double stepmin;
G4double currentKinEnergy;
G4double currentRange;
G4double rangeinit;
G4double currentRadLength;
G4int currentMaterialIndex;
G4double Zold;
G4double Zeff,Z2,Z23,lnZ;
G4double coeffth1,coeffth2;
G4double coeffc1,coeffc2,coeffc3,coeffc4;
G4bool firstStep;
G4bool insideskin;
G4bool latDisplasmentbackup ;
G4bool displacementFlag;
G4double rangecut;
G4double drr,finalr;
};
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
inline void G4UrbanAdjointMscModel::SetNewDisplacementFlag(G4bool val)
{
displacementFlag = val;
}
inline
void G4UrbanAdjointMscModel::SetParticle(const G4ParticleDefinition* p)
{ const G4ParticleDefinition* p1 =p;
if (p->GetParticleName() =="adj_e-") p1= G4Electron::Electron();
if (p1 != particle) {
particle = p1;
mass = p1->GetPDGMass();
charge = p1->GetPDGCharge()/CLHEP::eplus;
ChargeSquare = charge*charge;
}
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
inline G4double G4UrbanAdjointMscModel::Randomizetlimit()
{
G4double temptlimit = tlimit;
if(tlimit > tlimitmin)
{
G4double delta = tlimit-tlimitmin;
do {
temptlimit = G4RandGauss::shoot(rndmEngineMod,tlimit,0.1*delta);
// Loop checking, 10-Apr-2016, Laszlo Urban
} while ((temptlimit < tlimit-delta) ||
(temptlimit > tlimit+delta));
}
else { temptlimit = tlimitmin; }
return temptlimit;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
inline void G4UrbanAdjointMscModel::UpdateCache()
{
lnZ = G4Log(Zeff);
// correction in theta0 formula
G4double w = G4Exp(lnZ/6.);
G4double facz = 0.990395+w*(-0.168386+w*0.093286) ;
coeffth1 = facz*(1. - 8.7780e-2/Zeff);
coeffth2 = facz*(4.0780e-2 + 1.7315e-4*Zeff);
// tail parameters
G4double Z13 = w*w;
coeffc1 = 2.3785 - Z13*(4.1981e-1 - Z13*6.3100e-2);
coeffc2 = 4.7526e-1 + Z13*(1.7694 - Z13*3.3885e-1);
coeffc3 = 2.3683e-1 - Z13*(1.8111 - Z13*3.2774e-1);
coeffc4 = 1.7888e-2 + Z13*(1.9659e-2 - Z13*2.6664e-3);
Z2 = Zeff*Zeff;
Z23 = Z13*Z13;
Zold = Zeff;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
inline
G4double G4UrbanAdjointMscModel::SimpleScattering(G4double xmeanth, G4double x2meanth)
{
// 'large angle scattering'
// 2 model functions with correct xmean and x2mean
G4double a = (2.*xmeanth+9.*x2meanth-3.)/(2.*xmeanth-3.*x2meanth+1.);
G4double prob = (a+2.)*xmeanth/a;
// sampling
G4double cth = 1.;
if(rndmEngineMod->flat() < prob) {
cth = -1.+2.*G4Exp(G4Log(rndmEngineMod->flat())/(a+1.));
} else {
cth = -1.+2.*rndmEngineMod->flat();
}
return cth;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#endif