EvtBtoXsgammaKagan.hh

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#ifndef EVTBTOXSGAMMAKAGAN_HH
#define EVTBTOXSGAMMAKAGAN_HH
 
#include "EvtGenModels/EvtBtoXsgammaAbsModel.hh"
 
#include <vector>
 
// Description:
//       Implimentation of the Kagan-Neubert model for non-resonant
//       B->Xs,gamma decays.
// Description:
//       Routine to perform two-body non-resonant B->Xs,gamma decays.
//       The X_s mass spectrum generated is based on the Kagan-Neubert model.
//       See hep-ph/9805303 for the model details and input parameters.
//
//       The input parameters are 1:fermi_model, 2:mB, 3:mb, 4:mu, 5:lam1,
//       6:delta, 7:z, 8:nIntervalS, 9:nIntervalmH. Choosing fermi_model=1
//       uses an exponential shape function, fermi_model=2 uses a gaussian
//       shape function and fermi_model=3 a roman shape function. The complete mass
//       spectrum for a given set of input parameters is calculated from
//       scratch in bins of nIntervalmH. The s22, s27 and s28 coefficients are calculated
//       in bins of nIntervalS. As the program includes lots of integration, the
//       theoretical hadronic mass spectra is computed for the first time
//       the init method is called. Then, all the other times (eg if we want to decay a B0
//       as well as an anti-B0) the vector mass info stored the first time is used again.
 
class EvtBtoXsgammaKagan : public EvtBtoXsgammaAbsModel {
  public:
    void init( int, double* ) override;
 
    void computeHadronicMass( int, double* );
 
    void getDefaultHadronicMass();
 
    double GetMass( int code ) override;
 
    double CalcAlphaS( double );
 
    void CalcWilsonCoeffs();
    void CalcDelta();
    double Fz( double );
 
  private:
    //Input parameters
    double m_mb;
    double m_mB;
    double m_delta;
    double m_nIntervalS;
    double m_nIntervalmH;
    double m_lambdabar;
    double m_lam1;
    double m_mHmin;
    double m_mHmax;
    //Other parameters
    double m_r7;
    double m_gam77;
    double m_gam27;
    double m_gam87;
    double m_beta0;
    double m_beta1;
    double m_alphasmZ;
    double m_mZ;
    double m_z;
    double m_fz;
    double m_lam2;
    double m_kappabar;
    double m_rer2;
    double m_rer8;
    double m_kSLemmu;
    double m_mW;
    double m_mt;
    double m_ms;
    double m_mu;
 
    double m_c2mu;
    double m_c70mu;
    double m_c80mu;
    double m_c71mu;
    double m_c7emmu;
 
    double m_cDeltatot;
 
    double m_alpha;
    double m_alphasmW;
    double m_alphasmt;
    double m_alphasmu;
    double m_alphasmubar;
    double m_etamu;
 
    std::vector<double> m_mHVect;
 
    static double ReG( double );
    static double ImG( double );
    static double s77( double );
    static double s88( double, double, double );
    static double s78( double );
    static double s22Func( double var, const std::vector<double>& coeffs );
    static double s27Func( double var, const std::vector<double>& coeffs );
 
    static double Delta( double, double );
    static double DeltaFermiFunc( double, const std::vector<double>& coeffs1,
                                  const std::vector<double>& coeffs2,
                                  const std::vector<double>& coeffs3 );
    static double s77FermiFunc( double, const std::vector<double>& coeffs1,
                                const std::vector<double>& coeffs2 );
    static double s88FermiFunc( double, const std::vector<double>& coeffs1,
                                const std::vector<double>& coeffs2,
                                const std::vector<double>& coeffs3 );
    static double s78FermiFunc( double, const std::vector<double>& coeffs1,
                                const std::vector<double>& coeffs2 );
    static double s22FermiFunc( double, std::vector<double>& coeffs );
    static double s27FermiFunc( double, std::vector<double>& coeffs );
    static double s28FermiFunc( double, std::vector<double>& coeffs );
    static double GetArrayVal( double, double, double, double,
                               std::vector<double> );
    static double sFermiFunc( double, const std::vector<double>& coeffs1,
                              const std::vector<double>& coeffs2,
                              const std::vector<double>& coeffs3,
                              const std::vector<double>& coeffs4 );
    static double FermiFunc( double, const std::vector<double>& coeffs );
    static double diLogFunc( double );
    static double diLogMathematica( double );
    std::vector<double> m_massHad, m_brHad;
    static double m_intervalMH;
    static bool m_bbprod;
};
 
#endif