Geant4  10.00.p02
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);
53  G4ThreeVector p;
54 
55  do {
56  p=G4ThreeVector(2.*G4UniformRand()-1.,
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 
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)
75 
76 };
77 
78 #endif
79 
G4double cbrt(G4double x)
CLHEP::Hep3Vector G4ThreeVector
int G4int
Definition: G4Types.hh:78
G4double density
Definition: TRTMaterials.hh:39
#define G4UniformRand()
Definition: Randomize.hh:87
G4double GetFermiMomentum(G4double density)
void Init(G4int anA, G4int aZ)
G4ThreeVector GetMomentum(G4double density, G4double maxMomentum=-1.)
double G4double
Definition: G4Types.hh:76