Evtbs2llGammaISRFSRAmp.hh

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#ifndef EVTBSTOLLGAMMAISRFSR_AMP_HH
#define EVTBSTOLLGAMMAISRFSR_AMP_HH
 
class EvtId;
class EvtAmp;
class EvtParticle;
class Evtbs2llGammaFF;
class EvtbTosllWilsCoeffNLO;
 
// Description: Preparation of the decay amplitude for the process:
//              B^0_{q}(p,M1) -> gamma(k) ell^+(p1,m) ell^-(p2,m).
//              See the Internal LHCb Note LHCb-INT-2011-011.
//
// Note: The code of this module is based on the EvtbTosllVectorAmp.cpp
//       module code.
//       The main functiom for the amplitude calculation retuns the
//       amplitude for the decay  B -> gamma ell^+ ell^-
//       In our calculations we assume, that photon is the first
//       daughter particle (iG=0) and leptons are the second and thirds
//       daughter particles (il1=1 and il2=2).
 
class Evtbs2llGammaISRFSRAmp {
  public:
    void CalcAmp( EvtParticle* parent, EvtAmp& amp, Evtbs2llGammaFF* formFactors,
                  EvtbTosllWilsCoeffNLO* WilsCoeff, double mu, int Nf, int sr,
                  int res_swch, int ias, double Egamma_min, double CKM_A,
                  double CKM_lambda, double CKM_barrho, double CKM_bareta,
                  double mumumass_min );
 
    double CalcMaxProb( EvtId parnum, EvtId photnum, EvtId l1num, EvtId l2num,
                        Evtbs2llGammaFF* formFactors,
                        EvtbTosllWilsCoeffNLO* WilsCoeff, double mu, int Nf,
                        int sr, int res_swch, int ias, double Egamma_min,
                        double CKM_A, double CKM_lambda, double CKM_barrho,
                        double CKM_bareta, double mumumass_min );
 
    double lambda( double a, double b, double c );
};
 
#endif