PHOTONS%2B%2B/Tools/Weight_YFS.H

0001 #ifndef PHOTONS_Tools_Weight_YFS_H
0002 #define PHOTONS_Tools_Weight_YFS_H
0003
0004 #include "PHOTONS++/Tools/Weight_Base.H"
0005
0006 namespace PHOTONS {
0007   class Weight_YFS: public Weight_Base {
0008     private:
0009       double          m_nbar;
0010       double          m_Y;
0011       double          m_Ymax;
0012
0013       virtual void CalculateWeight();
0014       virtual void CalculateMax();
0015
0016     public:
0017       Weight_YFS(const ATOOLS::Particle_Vector&, const ATOOLS::Particle_Vector&,
0018                  const double&, const double&);
0019       virtual ~Weight_YFS();
0020   };
0021
0022
0023
0024
0025   /*!
0026     \file Weight_YFS.H
0027     \brief contains the class Weight_YFS
0028   */
0029
0030   /*!
0031     \class Weight_YFS
0032     \brief calculates \f$ W_{YFS} \f$ of the the event given
0033   */
0034   ////////////////////////////////////////////////////////////////////////////////////////////////////
0035   // Description of member variable of Weight_YFS
0036   ////////////////////////////////////////////////////////////////////////////////////////////////////
0037   /*!
0038     \var double Weight_YFS::m_nbar
0039     \brief avarage photon number of the configuration
0040   */
0041
0042   /*!
0043     \var double Weight_YFS::m_Y
0044     \brief YFS_Form_Factor of the event
0045   */
0046
0047   /*!
0048     \var double Weight_YFS::m_Ymax
0049     \brief YFS_Form_Factor of an event with \f$ K=0 \f$
0050   */
0051   ////////////////////////////////////////////////////////////////////////////////////////////////////
0052   // Description of member methods for Weight_YFS
0053   ////////////////////////////////////////////////////////////////////////////////////////////////////
0054   /*!
0055     \fn Weight_YFS::Weight_YFS(const Particle_Vector, const Particle_Vector, const double, const double)
0056     \brief initialises weight variables, calculates both form factors and calculates the weight and the maximum weight
0057
0058     The values to be passed are the multipole after corrections, the multipole before corrections, the infrared cut-off used in the photon generation and the avarage photon number of the configuration.
0059
0060     The maximum weight actually contains the weight of a event with \f$ K=0 \f$ which is allways smaller than the actual weight of any event with finite photon momentum, but this contribution is needed for the maximum weight of the overall event.
0061
0062     Uses the <tt>YFS_Form_Factor</tt> class to calculate the YFS-Form-Factor.
0063   */
0064
0065   /*!
0066     \fn void Weight_YFS::CalculateWeight()
0067     \brief calculates the weight of the event
0068
0069     The weight is \f$ W_{YFS} = \exp(Y+\bar{n}) \f$.
0070   */
0071
0072   /*!
0073     \fn void Weight_YFS::CalculateMax()
0074     \brief calculates the weight of an event with \f$ K=0 \f$
0075
0076     The "maximum weight" is actually a minimum weight if one looks only at the YFS_Form_Factor contribution. But in terms of the overall weight, the value at \f$ K=0 \f$ is needed.
0077   */
0078 }
0079
0080 #endif