Geant4 9.6.0
Toolkit for the simulation of the passage of particles through matter
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G4FermiMomentum.hh
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28#ifndef G4FermiMomentum_h
29#define G4FermiMomentum_h 1
30
31#include "globals.hh"
32#include "G4ThreeVector.hh"
33#include "Randomize.hh"
34
36{
37
38 public:
41
42 inline void Init(G4int anA, G4int aZ) {theA = anA; theZ = aZ;}
43
45 {
46 return constofpmax * cbrt(density * theA);
47 }
48
50 G4double maxMomentum=-1.)
51 {
52 if (maxMomentum < 0 ) maxMomentum=GetFermiMomentum(density);
54
55 do {
57 2.*G4UniformRand()-1.,
58 2.*G4UniformRand()-1.);
59 } while ( p.mag() > 1. );
60 return p*maxMomentum;
61 }
62
63 private:
64
65 G4double cbrt(G4double x) { return std::pow(x,1./3.); }
66
67 private:
68
69 G4int theA;
70 G4int theZ;
71 // pmax= hbar * c * ( 3* pi**2 * rho )**(1/3) =
72 // hbar * c * ( 3* pi**2 )**(1/3) * rho**(1/3)=
73 // constofpmax * rho**(1/3)
74 G4double constofpmax;
75
76};
77
78#endif
79
CLHEP::Hep3Vector G4ThreeVector
double G4double
Definition: G4Types.hh:64
int G4int
Definition: G4Types.hh:66
#define G4UniformRand()
Definition: Randomize.hh:53
double mag() const
G4ThreeVector GetMomentum(G4double density, G4double maxMomentum=-1.)
G4double GetFermiMomentum(G4double density)
void Init(G4int anA, G4int aZ)