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G4SampleResonance.hh
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26 
27 #ifndef G4SampleResonance_h
28 #define G4SampleResonance_h 1
29 
30 // ------------------------------------------------------------
31 // GEANT 4 class header file
32 //
33 // ---------------- G4SampleResonance ----------------
34 // by Henning Weber, March 2001.
35 // helper class for sampling resonance masses
36 // ------------------------------------------------------------
37 
38 #include "globals.hh"
39 #include <map>
40 #include "G4ParticleDefinition.hh"
41 #include "G4Log.hh"
42 
44 {
45 public:
46 
48  G4double SampleMass(const G4double poleMass,
49  const G4double gamma,
50  const G4double minMass,
51  const G4double maxMass) const;
52  G4double SampleMass(const G4ParticleDefinition* p, const G4double maxMass) const;
53 
54 private:
55 
56  G4double BrWigInt0(const G4double x, const G4double gamma, const G4double m0) const
57  { return 2.0*gamma*std::atan( 2.0 * (x-m0)/ gamma ); }
58 
59  G4double BrWigInt1(const G4double x, const G4double gamma, const G4double m0) const
60  { return 0.5*gamma*gamma*G4Log( (x-m0)*(x-m0)+gamma*gamma/4.0 ) + m0*BrWigInt0(x,gamma,m0); }
61 
62  G4double BrWigInv(const G4double x, const G4double gamma, const G4double m0) const
63  { return 0.5*gamma*std::tan( 0.5*x/gamma )+m0; }
64 
65 public:
66 
67  typedef std::map<const G4ParticleDefinition*, G4double, std::less<const G4ParticleDefinition*> >::const_iterator minMassMapIterator;
68  typedef std::map<const G4ParticleDefinition*, G4double, std::less<const G4ParticleDefinition*> > minMassMapType;
69 
70 private:
71 
73 
74 };
75 
76 
77 #endif
78 
79 
80 
81 
82 
83