Decay/General/FRVDecayer.h

0001 // -*- C++ -*-
0002 //
0003 // FRVDecayer.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_FRVDecayer_H
0010 #define HERWIG_FRVDecayer_H
0011 //
0012 // This is the declaration of the FRVDecayer class.
0013 //
0014
0015 #include "GeneralTwoBodyDecayer.h"
0016 #include "ThePEG/Repository/EventGenerator.h"
0017 #include "ThePEG/Helicity/Vertex/Vector/RFVVertex.h"
0018
0019 namespace Herwig {
0020 using namespace ThePEG;
0021 using Helicity::RFVVertexPtr;
0022
0023   /** \ingroup Decay
0024    * The FRVDecayer class implements the decay of a fermion
0025    * to a spin-3/2 fermion and a vector in a general model. It holds an RFVVertex
0026    * pointer that must be typecast from the VertexBase pointer held in
0027    * GeneralTwoBodyDecayer. It implents the virtual functions me2() and
0028    * partialWidth().
0029    *
0030    * @see GeneralTwoBodyDecayer
0031    */
0032 class FRVDecayer: public GeneralTwoBodyDecayer {
0033
0034 public:
0035
0036   /**
0037    * The default constructor.
0038    */
0039   FRVDecayer() {}
0040
0041 public:
0042
0043   /** @name Virtual functions required by the Decayer class. */
0044   //@{
0045   /**
0046    * Return the matrix element squared for a given mode and phase-space channel.
0047    * @param ichan The channel we are calculating the matrix element for.
0048    * @param part The decaying Particle.
0049    * @param outgoing The particles produced in the decay
0050    * @param momenta  The momenta of the particles produced in the decay
0051    * @param meopt Option for the calculation of the matrix element
0052    * @return The matrix element squared for the phase-space configuration.
0053    */
0054   double me2(const int ichan,const Particle & part,
0055          const tPDVector & outgoing,
0056          const vector<Lorentz5Momentum> & momenta,
0057          MEOption meopt) const;
0058
0059   /**
0060    *   Construct the SpinInfos for the particles produced in the decay
0061    */
0062   virtual void constructSpinInfo(const Particle & part,
0063                  ParticleVector outgoing) const;
0064
0065
0066   /**
0067    * Function to return partial Width
0068    * @param inpart The decaying particle.
0069    * @param outa One of the decay products.
0070    * @param outb The other decay product.
0071    */
0072   virtual Energy partialWidth(PMPair inpart, PMPair outa,
0073                   PMPair outb) const;
0074
0075   /**
0076    *  Set the information on the decay
0077    */
0078   virtual void setDecayInfo(PDPtr incoming, PDPair outgoing,
0079                 vector<VertexBasePtr>,
0080                 map<ShowerInteraction,VertexBasePtr> &,
0081                 const vector<map<ShowerInteraction,VertexBasePtr> > &,
0082                 map<ShowerInteraction,VertexBasePtr>);
0083   //@}
0084
0085 public:
0086
0087   /** @name Functions used by the persistent I/O system. */
0088   //@{
0089   /**
0090    * Function used to write out object persistently.
0091    * @param os the persistent output stream written to.
0092    */
0093   void persistentOutput(PersistentOStream & os) const;
0094
0095   /**
0096    * Function used to read in object persistently.
0097    * @param is the persistent input stream read from.
0098    * @param version the version number of the object when written.
0099    */
0100   void persistentInput(PersistentIStream & is, int version);
0101   //@}
0102
0103   /**
0104    * The standard Init function used to initialize the interfaces.
0105    * Called exactly once for each class by the class description system
0106    * before the main function starts or
0107    * when this class is dynamically loaded.
0108    */
0109   static void Init();
0110
0111 protected:
0112
0113   /** @name Clone Methods. */
0114   //@{
0115   /**
0116    * Make a simple clone of this object.
0117    * @return a pointer to the new object.
0118    */
0119   virtual IBPtr clone() const;
0120
0121   /** Make a clone of this object, possibly modifying the cloned object
0122    * to make it sane.
0123    * @return a pointer to the new object.
0124    */
0125   virtual IBPtr fullclone() const;
0126   //@}
0127
0128 private:
0129
0130   /**
0131    * The assignment operator is private and must never be called.
0132    * In fact, it should not even be implemented.
0133    */
0134   FRVDecayer & operator=(const FRVDecayer &) = delete;
0135
0136 private:
0137
0138   /**
0139    *  Abstract pointer to AbstractFRVVertex
0140    */
0141   vector<AbstractRFVVertexPtr> vertex_;
0142
0143   /**
0144    * Pointer to the perturbative vertex
0145    */
0146   vector<RFVVertexPtr> perturbativeVertex_;
0147
0148   /**
0149    *  Spin density matrix
0150    */
0151   mutable RhoDMatrix rho_;
0152
0153   /**
0154    *  Spinor wavefunction
0155    */
0156   mutable vector<SpinorWaveFunction>    wave_   ;
0157
0158   /**
0159    *  Barred spinor wavefunction
0160    */
0161   mutable vector<SpinorBarWaveFunction> wavebar_;
0162
0163   /**
0164    *  RS Spinor wavefunction
0165    */
0166   mutable vector<RSSpinorWaveFunction>    RSwave_   ;
0167
0168   /**
0169    *  Barred RS spinor wavefunction
0170    */
0171   mutable vector<RSSpinorBarWaveFunction> RSwavebar_;
0172
0173   /**
0174    *  Polarization vectors
0175    */
0176   mutable vector<VectorWaveFunction> vector_;
0177 };
0178
0179 }
0180
0181 #endif /* HERWIG_FRVDecayer_H */