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G4HadPhaseSpaceGenbod.hh
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26 // $Id$
27 //
28 // Multibody "phase space" generator using GENBOD (CERNLIB W515) method.
29 //
30 // Author: Michael Kelsey (SLAC) <kelsey@slac.stanford.edu>
31 
32 #ifndef G4HadPhaseSpaceGenbod_HH
33 #define G4HadPhaseSpaceGenbod_HH 1
34 
36 
37 
39 public:
40  G4HadPhaseSpaceGenbod(G4int verbose=0);
41  virtual ~G4HadPhaseSpaceGenbod() {;}
42 
43 protected:
44  virtual void GenerateMultiBody(G4double initialMass,
45  const std::vector<G4double>& masses,
46  std::vector<G4LorentzVector>& finalState);
47 
48 protected:
49  void Initialize(G4double initialMass,
50  const std::vector<G4double>& masses);
51 
52  void FillRandomBuffer();
53 
54  void ComputeWeightScale(const std::vector<G4double>& masses);
55 
56  void FillEnergySteps(G4double initialMass,
57  const std::vector<G4double>& masses);
58 
59  void GenerateMomenta(const std::vector<G4double>& masses,
60  std::vector<G4LorentzVector>& finalState);
61 
62  void AccumulateFinalState(size_t i,
63  const std::vector<G4double>& masses,
64  std::vector<G4LorentzVector>& finalState);
65 
66  G4bool AcceptEvent() const; // Use accept-reject to generate distribution
67  G4double ComputeWeight() const;
68 
69 private:
70  size_t nFinal; // Number of final state particles
71  G4double totalMass; // Sum of final state masses
72  G4double massExcess; // Available kinetic energy
73  G4double weightMax; // Maximum possible weight
74  G4int nTrials; // Accept/reject cycles taken
75 
76  std::vector<G4double> msum; // Cumulative sum of masses
77  std::vector<G4double> msq; // Final state squared masses
78  std::vector<G4double> rndm; // Random sequence for effective masses
79  std::vector<G4double> meff; // Random final-state effective masses
80  std::vector<G4double> pd; // Random momentum magnitudes
81 };
82 
83 #endif /* G4HadPhaseSpaceGenbod_HH */
void FillEnergySteps(G4double initialMass, const std::vector< G4double > &masses)
void GenerateMomenta(const std::vector< G4double > &masses, std::vector< G4LorentzVector > &finalState)
void ComputeWeightScale(const std::vector< G4double > &masses)
void AccumulateFinalState(size_t i, const std::vector< G4double > &masses, std::vector< G4LorentzVector > &finalState)
G4double ComputeWeight() const
virtual void GenerateMultiBody(G4double initialMass, const std::vector< G4double > &masses, std::vector< G4LorentzVector > &finalState)
int G4int
Definition: G4Types.hh:78
G4HadPhaseSpaceGenbod(G4int verbose=0)
bool G4bool
Definition: G4Types.hh:79
void Initialize(G4double initialMass, const std::vector< G4double > &masses)
double G4double
Definition: G4Types.hh:76