EvtPFermi.hh

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#ifndef EVTPFERMI_HH
#define EVTPFERMI_HH

// Description:
//   DFN model:
//      F(k+) = N (1-x)^a exp((1+a)x) ,x=k+/(mB-mb)
//      the fermi motion distribution according to
//      hep-ph/9905351 v2
//   BLNP model:
//      F(what,Lambda,b) = pow(_b,_b)/(tgamma(_b)*_Lambda)*pow(what/_Lambda,_b-1)*
//                           exp(-_b*what/Lambda);
//      the leading order shape function (exp) (hep-ph/0504071)

class EvtPFermi final {
  public:
    // Constructors

    EvtPFermi( const double& a, const double& mB, const double& mb );
    EvtPFermi( const double& Lambda, const double& b );

    // Operators

    // Selectors

    // Modifiers

    // Methods

    double getFPFermi( const double& kplus );
    double getSFBLNP( const double& what );

  protected:
    // Helper functions

  private:
    // Friends

    // Data members

    double _a;
    double _mb;
    double _mB;
    double _Lambda;
    double _b;
};

#endif    // EVTPFERMI_HH