include/EvtGenBase/EvtTwoBodyKine.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVT_TWO_BODY_KINE_HH
0022 #define EVT_TWO_BODY_KINE_HH
0023
0024 #include <iostream>
0025
0026 // Descriptions of the kinematics of a two-body decay.
0027
0028 class EvtTwoBodyKine {
0029   public:
0030     enum Index
0031     {
0032         A,
0033         B,
0034         AB
0035     };
0036
0037     EvtTwoBodyKine();
0038     EvtTwoBodyKine( double mA, double mB, double mAB );
0039
0040     // Accessors
0041
0042     inline double mA() const { return _mA; }
0043     inline double mB() const { return _mB; }
0044     inline double mAB() const { return _mAB; }
0045     double m( Index i = AB ) const;
0046
0047     // Momentum of the other two particles in the
0048     // rest-frame of particle i.
0049
0050     double p( Index i = AB ) const;
0051
0052     // Energy of particle i in the rest frame of particle j
0053
0054     double e( Index i, Index j ) const;
0055
0056     void print( std::ostream& os ) const;
0057
0058   private:
0059     double _mA;
0060     double _mB;
0061     double _mAB;
0062 };
0063
0064 std::ostream& operator<<( std::ostream& os, const EvtTwoBodyKine& p );
0065
0066 #endif