include/Geant4/G4LorentzConvertor.hh

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0025 //
0026 //
0027 // 20100108  Michael Kelsey -- Use G4LorentzVector internally
0028 // 20100120  M. Kelsey -- BUG FIX:  scm_momentum should be G4ThreeVector
0029 // 20100126  M. Kelsey -- Remove G4CascadeMomentum, use G4LorentzVector directly
0030 // 20100519  M. Kelsey -- Add interfaces to pass G4InuclParticles directly
0031 // 20100616  M. Kelsey -- Report bullet and target four-momenta when set
0032 // 20100915  M. Kelsey -- Move constructors to .cc file, add initializers
0033 // 20110602  M. Kelsey -- Drop some unnecessary kinematics intermediates
0034
0035 #ifndef G4LORENTZ_CONVERTOR_HH
0036 #define G4LORENTZ_CONVERTOR_HH
0037
0038 #include "globals.hh"
0039 #include "G4LorentzVector.hh"
0040 #include "G4ThreeVector.hh"
0041
0042 class G4InuclParticle;
0043
0044 class G4LorentzConvertor {
0045 public:
0046   G4LorentzConvertor();
0047
0048   G4LorentzConvertor(const G4LorentzVector& bmom, G4double bmass,
0049              const G4LorentzVector& tmom, G4double tmass);
0050
0051   G4LorentzConvertor(const G4InuclParticle* bullet,
0052              const G4InuclParticle* target);
0053
0054   void setVerbose(G4int vb=0) { verboseLevel = vb; }
0055
0056   void setBullet(const G4InuclParticle* bullet);
0057   void setTarget(const G4InuclParticle* target);
0058
0059   void setBullet(const G4InuclParticle& bullet) { setBullet(&bullet); }
0060   void setTarget(const G4InuclParticle& target) { setTarget(&target); }
0061
0062   // Use correct four-vectors as input
0063   void setBullet(const G4LorentzVector& bmom) {
0064     bullet_mom = bmom;
0065     if (verboseLevel > 3) printBullet();
0066   }
0067
0068   void setTarget(const G4LorentzVector& bmom) {
0069     target_mom = bmom;
0070     if (verboseLevel > 3) printTarget();
0071   }
0072
0073   // These functions "repair" input 4-vectors using specified mass
0074   void setBullet(const G4LorentzVector& bmom, G4double bmass) {
0075     bullet_mom.setVectM(bmom.vect(), bmass);
0076     if (verboseLevel > 3) printBullet();
0077   }
0078
0079   void setTarget(const G4LorentzVector& tmom, G4double tmass) {
0080     target_mom.setVectM(tmom.vect(), tmass);
0081     if (verboseLevel > 3) printTarget();
0082   }
0083
0084   // Select reference frame for boosts, rotations, etc.
0085   void toTheCenterOfMass();
0086   void toTheTargetRestFrame();
0087   void fillKinematics();    // Common calculations after either of above
0088
0089   G4LorentzVector backToTheLab(const G4LorentzVector& mom) const;
0090
0091   // Four-vectors of bullet and target in last chosen reference frame
0092   const G4LorentzVector& getBullet() const { return bullet_mom; }
0093   const G4LorentzVector& getTarget() const { return target_mom; }
0094
0095   G4double getKinEnergyInTheTRS() const;
0096   G4double getTotalSCMEnergy() const { return ecm_tot; }
0097   G4double getSCMMomentum() const { return scm_momentum.rho(); }
0098   G4double getTRSMomentum() const;
0099
0100   G4LorentzVector rotate(const G4LorentzVector& mom) const;
0101
0102   G4LorentzVector rotate(const G4LorentzVector& mom1,
0103              const G4LorentzVector& mom) const;
0104
0105   G4bool reflectionNeeded() const;
0106
0107   G4bool trivial() const { return degenerated; }
0108
0109   // Reporting functions for diagnostics
0110   void printBullet() const;
0111   void printTarget() const;
0112
0113 private:
0114   static const G4double small;
0115
0116   G4int verboseLevel;
0117   G4LorentzVector bullet_mom;
0118   G4LorentzVector target_mom;
0119
0120   G4LorentzVector scm_momentum;     // CM momentum relative to target/bullet
0121   G4ThreeVector   scm_direction;    // Unit vector to reduce repeated calcs
0122
0123   // Buffer variables for doing ::rotate() calculations
0124   G4ThreeVector velocity;
0125   G4double v2;
0126   G4double ecm_tot;
0127   G4double valong;
0128   G4bool degenerated;
0129 };
0130
0131 #endif // G4LORENTZ_CONVERTOR_HH