Decay/General/GeneralCurrentDecayer.h

0001 // -*- C++ -*-
0002 //
0003 // GeneralCurrentDecayer.h is a part of Herwig - A multi-purpose Monte Carlo event generator
0004 // Copyright (C) 2002-2019 The Herwig Collaboration
0005 //
0006 // Herwig is licenced under version 3 of the GPL, see COPYING for details.
0007 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
0008 //
0009 #ifndef HERWIG_GeneralCurrentDecayer_H
0010 #define HERWIG_GeneralCurrentDecayer_H
0011 //
0012 // This is the declaration of the GeneralCurrentDecayer class.
0013 //
0014
0015 #include "Herwig/Decay/DecayIntegrator.h"
0016 #include "Herwig/Decay/WeakCurrents/WeakCurrent.h"
0017 #include "Herwig/Decay/PhaseSpaceMode.h"
0018 #include "ThePEG/Helicity/Vertex/VertexBase.h"
0019 #include "GeneralCurrentDecayer.fh"
0020
0021 namespace Herwig {
0022 using namespace ThePEG;
0023 using Helicity::VertexBasePtr;
0024
0025 /**
0026  * Here is the documentation of the GeneralCurrentDecayer class.
0027  *
0028  * @see \ref GeneralCurrentDecayerInterfaces "The interfaces"
0029  * defined for GeneralCurrentDecayer.
0030  */
0031 class GeneralCurrentDecayer: public DecayIntegrator {
0032
0033 public:
0034
0035   /**
0036    * The default constructor.
0037    */
0038   GeneralCurrentDecayer() :
0039     maxmass_(5.*GeV), wgtmax_(0.) {}
0040
0041   /** @name Virtual functions required by the Decayer class. */
0042   //@{
0043   /**
0044    * Which of the possible decays is required
0045    * @param cc Is this mode the charge conjugate
0046    * @param parent The decaying particle
0047    * @param children The decay products
0048    */
0049   virtual int modeNumber(bool & cc, tcPDPtr parent,const tPDVector & children) const;
0050
0051   /**
0052    * Function to return partial Width
0053    * @param inpart Pointer to incoming particle data object
0054    * @param outa Pointer to first outgoing particle data object
0055    * @param currout Pointer to particles in the current
0056    */
0057   virtual Energy partialWidth(tPDPtr inpart, tPDPtr outa,
0058                   vector<tPDPtr> currout) = 0;
0059   //@}
0060
0061   /**
0062    *  set up the decay
0063    */
0064   void setDecayInfo(PDPtr in, PDPtr out, const vector<tPDPtr> & outCurrent,
0065             VertexBasePtr vertex, WeakCurrentPtr current,
0066             Energy maxmass);
0067
0068 public:
0069
0070   /** @name Functions used by the persistent I/O system. */
0071   //@{
0072   /**
0073    * Function used to write out object persistently.
0074    * @param os the persistent output stream written to.
0075    */
0076   void persistentOutput(PersistentOStream & os) const;
0077
0078   /**
0079    * Function used to read in object persistently.
0080    * @param is the persistent input stream read from.
0081    * @param version the version number of the object when written.
0082    */
0083   void persistentInput(PersistentIStream & is, int version);
0084   //@}
0085
0086   /**
0087    * The standard Init function used to initialize the interfaces.
0088    * Called exactly once for each class by the class description system
0089    * before the main function starts or
0090    * when this class is dynamically loaded.
0091    */
0092   static void Init();
0093
0094 protected:
0095
0096   /** @name Standard Interfaced functions. */
0097   //@{
0098   /**
0099    * Initialize this object after the setup phase before saving an
0100    * EventGenerator to disk.
0101    * @throws InitException if object could not be initialized properly.
0102    */
0103   virtual void doinit();
0104
0105   /**
0106    * Initialize this object. Called in the run phase just before
0107    * a run begins.
0108    */
0109   virtual void doinitrun();
0110   //@}
0111
0112 protected:
0113
0114   /**
0115    *  The number of the mode
0116    * @param cc Whether of not this is the charge conjugate of the defined mode
0117    * @param id The PDG codes of the particles
0118    */
0119   int modeNumber(bool & cc, vector<long> id) const;
0120
0121   /**
0122    *  Access to the map between the number of the mode and the modes in
0123    *  the current
0124    */
0125   unsigned int mode() const { return mode_; }
0126
0127   /**
0128    *  Access to the weak current
0129    */
0130   WeakCurrentPtr weakCurrent() const { return current_; }
0131
0132   /**
0133    * Get vertex pointer
0134    * @return a pointer to the vertex
0135    */
0136   VertexBasePtr vertex() const { return theVertex_; }
0137
0138 private:
0139
0140   /**
0141    * The assignment operator is private and must never be called.
0142    * In fact, it should not even be implemented.
0143    */
0144   GeneralCurrentDecayer & operator=(const GeneralCurrentDecayer &) = delete;
0145
0146 private:
0147
0148   /**
0149    * Pointer to vertex set in inheriting class
0150    */
0151   VertexBasePtr theVertex_;
0152
0153   /**
0154    * Incoming particle
0155    **/
0156   PDPtr inpart_;
0157
0158   /**
0159    * First outgoing particle
0160    */
0161   PDPtr outpart_;
0162
0163   /**
0164    *  Outgoing particles from the current
0165    */
0166   vector<tPDPtr> currentOut_;
0167
0168   /**
0169    * Pointer to the current
0170    */
0171   WeakCurrentPtr current_;
0172
0173   /**
0174    *  Maximum mass difference
0175    */
0176   Energy maxmass_;
0177
0178   /**
0179    * mapping of the modes to the currents
0180    */
0181   unsigned int mode_;
0182
0183   /**
0184    * location of the weights
0185    */
0186   int wgtloc_;
0187
0188   /**
0189    * the maximum weight
0190    */
0191   double wgtmax_;
0192
0193   /**
0194    *  The weights for the different channels
0195    */
0196   vector<double> weights_;
0197 };
0198
0199 }
0200
0201 #endif /* HERWIG_GeneralCurrentDecayer_H */