EvtVubBLNPHybrid.hh

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#ifndef EVTVUBBLNPHYBRID_HH
#define EVTVUBBLNPHYBRID_HH
 
#include "EvtGenBase/EvtDecayIncoherent.hh"
 
#include <vector>
 
class EvtParticle;
 
// tripleDiff from BLNPHybrid's notebook, based on hep-ph/0504071
//
// Description:
// Class to generate inclusive B to X_u l nu decays.
// This class is based on EvtVubBLNP by Sheila Mclachlin with an update to
// generate the inclusive decays in such a way that the right
// mix of inclusive and exclusive decays is obtained.
//
//NOTE:
// - A set of weights (for bins in the kinematic variables mX, q2, El)
//   is read from DECAY.DEC. This set of weights must be consistent
//   with the other parameters specified (excl. BF, non-res BF, mb, a).
// - If no binning/weights are specified in DECAY.DEC the hybrid
//   reweighting is not activated
 
class EvtVubBLNPHybrid : public EvtDecayIncoherent {
  public:
    std::string getName() const override;
 
    EvtDecayBase* clone() const override;
 
    void initProbMax() override;
 
    void init() override;
 
    void decay( EvtParticle* Bmeson ) override;
 
    void readWeights( int startArg = 0 );
 
    double getWeight( double mX, double q2, double El );
 
  private:
    //Input for hybrid modell
    enum
    {
        nParameters = 10,
        nVariables = 3
    };
    bool m_noHybrid = false;
    bool m_storeWhat = true;
    int m_nbins = 0;
    double m_masscut = 0.28;
    std::vector<double> m_bins_mX;
    std::vector<double> m_bins_q2;
    std::vector<double> m_bins_El;
    std::vector<double> m_weights;
 
    // Input parameters
    double m_mBB;
    double m_lambda2;
 
    // Shape function parameters
    double m_b;
    double m_Lambda;
    double m_Ecut;
    double m_wzero;
 
    // SF and SSF modes
    int m_itype;
    double m_dtype;
    int m_isubl;
 
    // flags
    int m_flag1;
    int m_flag2;
    int m_flag3;
 
    // Quark mass
    double m_mb;
 
    // Matching scales
    double m_muh;
    double m_mui;
    double m_mubar;
 
    // Perturbative quantities
    double m_CF;
    double m_CA;
 
    double m_beta0;
    double m_beta1;
    double m_beta2;
 
    double m_zeta3;
 
    double m_Gamma0;
    double m_Gamma1;
    double m_Gamma2;
 
    double m_gp0;
    double m_gp1;
 
    double m_Lbar;
    double m_mupisq;
    double m_moment2;
 
    int m_flagpower;
    int m_flag2loop;
 
    int m_maxLoop;
    double m_precision;
 
    std::vector<double> m_gvars;
 
    double rate3( double Pp, double Pl, double Pm );
    double F1( double Pp, double Pm, double muh, double mui, double mubar,
               double doneJS, double done1 );
    double F2( double Pp, double Pm, double muh, double mui, double mubar,
               double done3 );
    double F3( double Pp, double Pm, double muh, double mui, double mubar,
               double done2 );
    double DoneJS( double Pp, double Pm, double mui );
    double Done1( double Pp, double Pm, double mui );
    double Done2( double Pp, double Pm, double mui );
    double Done3( double Pp, double Pm, double mui );
    static double IntJS( double what, const std::vector<double>& vars );
    static double Int1( double what, const std::vector<double>& vars );
    static double Int2( double what, const std::vector<double>& vars );
    static double Int3( double what, const std::vector<double>& vars );
    static double g1( double w, const std::vector<double>& vars );
    static double g2( double w, const std::vector<double>& vars );
    static double g3( double w, const std::vector<double>& vars );
    static double Shat( double w, const std::vector<double>& vars );
    static double Mzero( double muf, double mu, double mupisq,
                         const std::vector<double>& vars );
    double wS( double w );
    double t( double w );
    double u( double w );
    double v( double w );
    double myfunction( double w, double Lbar, double mom2 );
    double myfunctionBIK( double w, double Lbar, double mom2 );
    double dU1nlo( double muh, double mui );
    double U1lo( double muh, double mui );
    double Sfun( double mu1, double mu2, double epsilon );
    double S0( double a1, double r );
    double S1( double a1, double r );
    double S2( double a1, double r );
    double aGamma( double mu1, double mu2, double epsilon );
    double agp( double mu1, double mu2, double epsilon );
    double alo( double muh, double mui );
    double anlo( double muh, double mui );    // d/depsilon of aGamma
    static double alphas( double mu, const std::vector<double>& vars );
    double PolyLog( double v, double z );
    static double Gamma( double z );
    static double Gamma( double a, double x );
    static double gamser( double a, double x, double LogGamma );
    static double gammcf( double a, double x, double LogGamma );
    double findBLNPWhat();
    std::vector<double> m_pf;
};
 
#endif