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G4LorentzConvertor.hh
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26 //
27 // 20100108 Michael Kelsey -- Use G4LorentzVector internally
28 // 20100120 M. Kelsey -- BUG FIX: scm_momentum should be G4ThreeVector
29 // 20100126 M. Kelsey -- Remove G4CascadeMomentum, use G4LorentzVector directly
30 // 20100519 M. Kelsey -- Add interfaces to pass G4InuclParticles directly
31 // 20100616 M. Kelsey -- Report bullet and target four-momenta when set
32 // 20100915 M. Kelsey -- Move constructors to .cc file, add initializers
33 // 20110602 M. Kelsey -- Drop some unnecessary kinematics intermediates
34 
35 #ifndef G4LORENTZ_CONVERTOR_HH
36 #define G4LORENTZ_CONVERTOR_HH
37 
38 #include "globals.hh"
39 #include "G4LorentzVector.hh"
40 #include "G4ThreeVector.hh"
41 
42 class G4InuclParticle;
43 
44 class G4LorentzConvertor {
45 public:
46  G4LorentzConvertor();
47 
48  G4LorentzConvertor(const G4LorentzVector& bmom, G4double bmass,
49  const G4LorentzVector& tmom, G4double tmass);
50 
51  G4LorentzConvertor(const G4InuclParticle* bullet,
52  const G4InuclParticle* target);
53 
54  void setVerbose(G4int vb=0) { verboseLevel = vb; }
55 
56  void setBullet(const G4InuclParticle* bullet);
57  void setTarget(const G4InuclParticle* target);
58 
59  void setBullet(const G4InuclParticle& bullet) { setBullet(&bullet); }
60  void setTarget(const G4InuclParticle& target) { setTarget(&target); }
61 
62  // Use correct four-vectors as input
63  void setBullet(const G4LorentzVector& bmom) {
64  bullet_mom = bmom;
65  if (verboseLevel > 3) printBullet();
66  }
67 
68  void setTarget(const G4LorentzVector& bmom) {
69  target_mom = bmom;
70  if (verboseLevel > 3) printTarget();
71  }
72 
73  // These functions "repair" input 4-vectors using specified mass
74  void setBullet(const G4LorentzVector& bmom, G4double bmass) {
75  bullet_mom.setVectM(bmom.vect(), bmass);
76  if (verboseLevel > 3) printBullet();
77  }
78 
79  void setTarget(const G4LorentzVector& tmom, G4double tmass) {
80  target_mom.setVectM(tmom.vect(), tmass);
81  if (verboseLevel > 3) printTarget();
82  }
83 
84  // Select reference frame for boosts, rotations, etc.
85  void toTheCenterOfMass();
86  void toTheTargetRestFrame();
87  void fillKinematics(); // Common calculations after either of above
88 
89  G4LorentzVector backToTheLab(const G4LorentzVector& mom) const;
90 
91  // Four-vectors of bullet and target in last chosen reference frame
92  const G4LorentzVector& getBullet() const { return bullet_mom; }
93  const G4LorentzVector& getTarget() const { return target_mom; }
94 
95  G4double getKinEnergyInTheTRS() const;
96  G4double getTotalSCMEnergy() const { return ecm_tot; }
97  G4double getSCMMomentum() const { return scm_momentum.rho(); }
98  G4double getTRSMomentum() const;
99 
100  G4LorentzVector rotate(const G4LorentzVector& mom) const;
101 
102  G4LorentzVector rotate(const G4LorentzVector& mom1,
103  const G4LorentzVector& mom) const;
104 
105  G4bool reflectionNeeded() const;
106 
107  G4bool trivial() const { return degenerated; }
108 
109  // Reporting functions for diagnostics
110  void printBullet() const;
111  void printTarget() const;
112 
113 private:
114  static const G4double small;
115 
116  G4int verboseLevel;
117  G4LorentzVector bullet_mom;
118  G4LorentzVector target_mom;
119 
120  G4LorentzVector scm_momentum; // CM momentum relative to target/bullet
121  G4ThreeVector scm_direction; // Unit vector to reduce repeated calcs
122 
123  // Buffer variables for doing ::rotate() calculations
124  G4ThreeVector velocity;
125  G4double v2;
126  G4double ecm_tot;
127  G4double valong;
128  G4bool degenerated;
129 };
130 
131 #endif // G4LORENTZ_CONVERTOR_HH