include/EvtGenModels/Evtbs2llGammaAmp.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVTBSTOLLGAMMA_AMP_HH
0022 #define EVTBSTOLLGAMMA_AMP_HH
0023
0024 class EvtId;
0025 class EvtAmp;
0026 class EvtParticle;
0027 class Evtbs2llGammaFF;
0028 class EvtbTosllWilsCoeffNLO;
0029
0030 // Description: Preparation of the decay amplitude for the process:
0031 //              B^0_{q}(p,M1) -> gamma(k) ell^+(p1,m) ell^-(p2,m).
0032 //
0033 // Note: The code of this module is based on the EvtbTosllVectorAmp.cpp
0034 //   module code.
0035 //   The main functiom for the amplitude calculation retuns the
0036 //   amplitude for the decay  B -> gamma ell^+ ell^-
0037 //   In our calculations we assume, that photon is the first
0038 //       daughter particle (iG=0) and leptons are the second and thirds
0039 //       daughter particles (il1=1 and il2=2).
0040
0041 class Evtbs2llGammaAmp {
0042   public:
0043     void CalcAmp( EvtParticle* parent, EvtAmp& amp, Evtbs2llGammaFF* formFactors,
0044                   EvtbTosllWilsCoeffNLO* WilsCoeff, double mu, int Nf,
0045                   int res_swch, int ias, double Egamma_min, double CKM_A,
0046                   double CKM_lambda, double CKM_barrho, double CKM_bareta );
0047
0048     double CalcMaxProb( EvtId parnum, EvtId photnum, EvtId l1num, EvtId l2num,
0049                         Evtbs2llGammaFF* formFactors,
0050                         EvtbTosllWilsCoeffNLO* WilsCoeff, double mu, int Nf,
0051                         int res_swch, int ias, double Egamma_min, double CKM_A,
0052                         double CKM_lambda, double CKM_barrho, double CKM_bareta );
0053
0054     double lambda( double a, double b, double c );
0055 };
0056
0057 #endif