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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 #include "G4Pow.hh"
35 
37 {
38 
39  public:
42 
43  inline void Init(G4int anA, G4int aZ) {theA = anA; theZ = aZ;}
44 
46  {
47  return constofpmax * cbrt(density * theA);
48  }
49 
51  G4double maxMomentum=-1.)
52  {
53  if (maxMomentum < 0 ) maxMomentum=GetFermiMomentum(density);
55 
56  do {
57  p=G4ThreeVector(2.*G4UniformRand()-1.,
58  2.*G4UniformRand()-1.,
59  2.*G4UniformRand()-1.);
60  } while ( p.mag() > 1. ); /* Loop checking, 30-Oct-2015, G.Folger */
61  return p*maxMomentum;
62  }
63 
64  private:
65 
66  G4double cbrt(G4double x) { return G4Pow::GetInstance()->A13(x); }
67 
68  private:
69 
70  G4int theA;
71  G4int theZ;
72  // pmax= hbar * c * ( 3* pi**2 * rho )**(1/3) =
73  // hbar * c * ( 3* pi**2 )**(1/3) * rho**(1/3)=
74  // constofpmax * rho**(1/3)
75  G4double constofpmax;
76 
77 };
78 
79 #endif
80 
static G4Pow * GetInstance()
Definition: G4Pow.cc:55
CLHEP::Hep3Vector G4ThreeVector
const char * p
Definition: xmltok.h:285
int G4int
Definition: G4Types.hh:78
#define G4UniformRand()
Definition: Randomize.hh:97
G4double GetFermiMomentum(G4double density)
void Init(G4int anA, G4int aZ)
G4double A13(G4double A) const
Definition: G4Pow.hh:132
G4ThreeVector GetMomentum(G4double density, G4double maxMomentum=-1.)
double G4double
Definition: G4Types.hh:76
double mag() const