EvtResonance.hh

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#ifndef EVTRESONANCE_HH
#define EVTRESONANCE_HH
 
#include "EvtGenBase/EvtVector4R.hh"
 
class EvtComplex;
 
class EvtResonance final {
  public:
    EvtResonance& operator=( const EvtResonance& );
 
    //constructor with all information about the resonance
    EvtResonance( const EvtVector4R& p4_p, const EvtVector4R& p4_d1,
                  const EvtVector4R& p4_d2, double ampl = 0.0, double theta = 0.0,
                  double gamma = 0.0, double bwm = 0.0, int spin = 0 );
 
    //accessors
    //return 4-momenta of the particles involved
    inline const EvtVector4R& p4_p() { return m_p4_p; }
    inline const EvtVector4R& p4_d1() { return m_p4_d1; }
    inline const EvtVector4R& p4_d2() { return m_p4_d2; }
 
    //return amplitude
    inline double amplitude() { return m_ampl; }
 
    //return theta
    inline double theta() { return m_theta; }
 
    //return gamma
    inline double gamma() { return m_gamma; }
 
    //return bwm
    inline double bwm() { return m_bwm; }
 
    //return spin
    inline int spin() { return m_spin; }
 
    //calculate amplitude for this resonance
    EvtComplex resAmpl();
 
    //calculate relativistic Breit-Wigner amplitude for P-decays of scalars
    EvtComplex relBrWig( int i );
 
  private:
    EvtVector4R m_p4_p, m_p4_d1, m_p4_d2;
    double m_ampl, m_theta, m_gamma, m_bwm;
    int m_spin;
};
 
#endif