G4eBremParametrizedModel.cc File Reference

#include "G4eBremParametrizedModel.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4Electron.hh"
#include "G4Positron.hh"
#include "G4Gamma.hh"
#include "Randomize.hh"
#include "G4Material.hh"
#include "G4Element.hh"
#include "G4ElementVector.hh"
#include "G4ProductionCutsTable.hh"
#include "G4ParticleChangeForLoss.hh"
#include "G4LossTableManager.hh"
#include "G4ModifiedTsai.hh"

Go to the source code of this file.

Functions
G4double	ScreenFunction1 (G4double ScreenVariable)
G4double	ScreenFunction2 (G4double ScreenVariable)
G4double	ComputeParametrizedDXSectionPerAtom (G4double kineticEnergy, G4double gammaEnergy, G4double Z)

Function Documentation

ComputeParametrizedDXSectionPerAtom()

G4double ComputeParametrizedDXSectionPerAtom	(	G4double	kineticEnergy,
		G4double	gammaEnergy,
		G4double	Z
	)

Definition at line 357 of file G4eBremParametrizedModel.cc.

                                                                                                       {
  G4double lnZ = std::log(Z); // 3.*(anElement->GetIonisation()->GetlogZ3());
  G4double FZ = lnZ* (4.- 0.55*lnZ);
  G4double ZZ = std::pow (Z*(Z+1.),1./3.); // anElement->GetIonisation()->GetZZ3();
  G4double Z3 = std::pow (Z,1./3.); // (anElement->GetIonisation()->GetZ3())
 
  G4double totalEnergy = kineticEnergy + electron_mass_c2;
 
  //  G4double x, epsil, greject, migdal, grejmax, q;
  G4double epsil, greject;
  G4double U  = log(kineticEnergy/electron_mass_c2);
  G4double U2 = U*U;
 
  // precalculated parameters
  G4double ah, bh;
 
if (kineticEnergy > tlow) {
       
    G4double ah1 = ah10 + ZZ* (ah11 + ZZ* ah12);
    G4double ah2 = ah20 + ZZ* (ah21 + ZZ* ah22);
    G4double ah3 = ah30 + ZZ* (ah31 + ZZ* ah32);
 
    G4double bh1 = bh10 + ZZ* (bh11 + ZZ* bh12);
    G4double bh2 = bh20 + ZZ* (bh21 + ZZ* bh22);
    G4double bh3 = bh30 + ZZ* (bh31 + ZZ* bh32);
 
    ah = 1.   + (ah1*U2 + ah2*U + ah3) / (U2*U);
    bh = 0.75 + (bh1*U2 + bh2*U + bh3) / (U2*U);
 
    // limit of the screening variable
    G4double screenfac =
      136.*electron_mass_c2/(Z3*totalEnergy);
 
    epsil = gammaEnergy/totalEnergy; //         epsil = x*kineticEnergy/totalEnergy;
        G4double screenvar = screenfac*epsil/(1.0-epsil);
        G4double F1 = max(ScreenFunction1(screenvar) - FZ ,0.);
        G4double F2 = max(ScreenFunction2(screenvar) - FZ ,0.);
 
 
    greject = (F1 - epsil* (ah*F1 - bh*epsil*F2))/8.; //  1./(42.392 - FZ);
 
    std::cout << " yy = "<<epsil<<std::endl;
    std::cout << " F1/(...) "<<F1/(42.392 - FZ)<<std::endl;
    std::cout << " F2/(...) "<<F2/(42.392 - FZ)<<std::endl;
    std::cout << " (42.392 - FZ) " << (42.392 - FZ) <<std::endl;
 
  } else {  
 
    G4double al0 = al00 + ZZ* (al01 + ZZ* al02);
    G4double al1 = al10 + ZZ* (al11 + ZZ* al12);
    G4double al2 = al20 + ZZ* (al21 + ZZ* al22);
 
    G4double bl0 = bl00 + ZZ* (bl01 + ZZ* bl02);
    G4double bl1 = bl10 + ZZ* (bl11 + ZZ* bl12);
    G4double bl2 = bl20 + ZZ* (bl21 + ZZ* bl22);
 
    ah = al0 + al1*U + al2*U2;
    bh = bl0 + bl1*U + bl2*U2;
 
    G4double x=gammaEnergy/kineticEnergy;
    greject=(1. + x* (ah + bh*x));
 
    /*
    // Compute the maximum of the rejection function
    grejmax = max(1. + xmin* (ah + bh*xmin), 1.+ah+bh);
    G4double xm = -ah/(2.*bh);
    if ( xmin < xm && xm < xmax) grejmax = max(grejmax, 1.+ xm* (ah + bh*xm));
    */
  }
 
 return greject;
}

ScreenFunction1()

G4double ScreenFunction1

(

G4double

ScreenVariable

)

Definition at line 323 of file G4eBremParametrizedModel.cc.

{
  G4double screenVal;
 
  if (ScreenVariable > 1.)
    screenVal = 42.24 - 8.368*std::log(ScreenVariable+0.952);
  else
    screenVal = 42.392 - ScreenVariable* (7.796 - 1.961*ScreenVariable);
 
  return screenVal;
} 

Referenced by ComputeParametrizedDXSectionPerAtom().

ScreenFunction2()

G4double ScreenFunction2

(

G4double

ScreenVariable

)

Definition at line 340 of file G4eBremParametrizedModel.cc.

{
  G4double screenVal;
 
  if (ScreenVariable > 1.)
    screenVal = 42.24 - 8.368*std::log(ScreenVariable+0.952);
  else
    screenVal = 41.734 - ScreenVariable* (6.484 - 1.250*ScreenVariable);
 
  return screenVal;
} 

Referenced by ComputeParametrizedDXSectionPerAtom().