EIC code displayed by LXR master/​include/​Herwig/​Decay/​FormFactors/​BtoSGammaHadronicMass.h	Source navigation Diff markup Identifier search General search
	Version: master test Revert   Change

File indexing completed on 2026-08-06 09:24:00

 // -*- C++ -*-
 //
 // BtoSGammaHadronicMass.h is a part of Herwig - A multi-purpose Monte Carlo event generator
 // Copyright (C) 2002-2019 The Herwig Collaboration
 //
 // Herwig is licenced under version 3 of the GPL, see COPYING for details.
 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
 //
 #ifndef HERWIG_BtoSGammaHadronicMass_H
 #define HERWIG_BtoSGammaHadronicMass_H
 //
 // This is the declaration of the BtoSGammaHadronicMass class.
 //
 
 #include "ThePEG/Interface/Interfaced.h"
 #include "BtoSGammaHadronicMass.fh"
 
 namespace Herwig {
 
 using namespace ThePEG;
 
 /** \ingroup Decay
  *
  * The BtoSGammaHadronicMass class is the base class for the implementation
  * of models of the hadronic mass spectrum in \f$B\to s\gamma\f$ decays.
  * Classes inheriting from this class should implement the hadronicMass()
  * member which should return a value of the hadronic mass selected from
  * the distribution.
  *
  * The parameters relating to the minimum and maximum values of the mass are stored
  * in this class.
  *
  */
 class BtoSGammaHadronicMass: public Interfaced {
 
 public:
 
   /**
    * The default constructor.
    */
   BtoSGammaHadronicMass() : _minMass(825*MeV),_maxMass(5300*MeV) {}
 
   /**
    * Virtual member which must be implemented in classes inheriting from this
    * class to return the hadronic mass.
    * @param mb The mass of the decaying B meson
    * @param mquark The minimum mass of the hadronic system based on the consistuent quark
    * masses.
    * @return The hadronic mass
    */
   virtual Energy hadronicMass(Energy mb,Energy mquark) =0;
 
   /**
    * Output the setup information for the particle database
    * @param os The stream to output the information to
    * @param header Whether or not to output the information for MySQL
    * @param create Whether or not to add a statement creating the object
    */
   virtual void dataBaseOutput(ofstream & os,bool header,bool create) const;
 
 public:
 
   /** @name Functions used by the persistent I/O system. */
   //@{
   /**
    * Function used to write out object persistently.
    * @param os the persistent output stream written to.
    */
   void persistentOutput(PersistentOStream & os) const;
 
   /**
    * Function used to read in object persistently.
    * @param is the persistent input stream read from.
    * @param version the version number of the object when written.
    */
   void persistentInput(PersistentIStream & is, int version);
   //@}
 
   /**
    * The standard Init function used to initialize the interfaces.
    * Called exactly once for each class by the class description system
    * before the main function starts or
    * when this class is dynamically loaded.
    */
   static void Init();
 
 protected:
 
   /** @name Access to the limits on the mass. */
   //@{
   /**
    *  Minimum mass
    */
   Energy minMass() const {return _minMass;}
 
   /**
    *  Maximum mass
    */
   Energy maxMass() const {return _maxMass;}
   //@}
 
   /** @name Functions for the fermi motion needed in classes inheriting from this */
   //@{
   /**
    * Exponential function of the form, \f$N(1-x)^ae^{-3\bar{\Lambda}^2x/\lambda_1}\f$,
    * where 
    * \f$x=k_+/\bar{\Lambda}\f$ taken from hep-ph/9805303
    * @param scale The energy scale, \f$k_+\f$, at which to evaluate the function.
    * @param lambda The hadronic scale, \f$\bar{\Lambda}\f$
    * @param a The shape parameter, \f$a\f$.
    * @param norm The normalisation, \f$N\f$.
    * @param lambda1 Scale related to kinetic energy of b quark, \f$\lambda_1\f$.
    */
   InvEnergy exponentialFermiFunction(Energy scale,Energy lambda, double a,
                      InvEnergy norm,Energy2 lambda1 ) const {
     double x(scale/lambda);
     return norm*pow(1.-x,a)*exp(-3.*sqr(lambda)/lambda1*x);
   }
   //@}
 
 private:
 
   /**
    * The assignment operator is private and must never be called.
    * In fact, it should not even be implemented.
    */
   BtoSGammaHadronicMass & operator=(const BtoSGammaHadronicMass &) = delete;
 
 private:
 
   /**
    * The minimum value of the hadronic mass
    */
   Energy _minMass;
 
   /**
    * The maximum value of the hadronic mass
    */
   Energy _maxMass;
 
 };
 
 }
 
 #endif /* HERWIG_BtoSGammaHadronicMass_H */

This page was automatically generated by the 2.3.7 LXR engine. The LXR team