Builtin/Amplitudes/MatchboxAmplitudellbarqqbarg.h

0001 // -*- C++ -*-
0002 //
0003 // MatchboxAmplitudellbarqqbarg.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_MatchboxAmplitudellbarqqbarg_H
0010 #define Herwig_MatchboxAmplitudellbarqqbarg_H
0011 //
0012 // This is the declaration of the MatchboxAmplitudellbarqqbarg class.
0013 //
0014
0015 #include "Herwig/MatrixElement/Matchbox/Builtin/Amplitudes/MatchboxZGammaAmplitude.h"
0016 #include "Herwig/MatrixElement/Matchbox/Builtin/Amplitudes/MatchboxCurrents.h"
0017
0018 namespace Herwig {
0019
0020 using namespace ThePEG;
0021
0022 /**
0023  * \ingroup Matchbox
0024  * \author Simon Platzer
0025  *
0026  * \brief MatchboxAmplitudellbarqqbarg
0027  */
0028 class MatchboxAmplitudellbarqqbarg:
0029     public MatchboxZGammaAmplitude, public MatchboxCurrents {
0030
0031 public:
0032
0033   /**
0034    * The default constructor.
0035    */
0036   MatchboxAmplitudellbarqqbarg();
0037
0038 public:
0039
0040   /**
0041    * Return true, if this amplitude can handle the given process.
0042    */
0043   virtual bool canHandle(const PDVector&) const;
0044
0045   /**
0046    * Return the (tree-level) order in \f$g_S\f$ in which this matrix
0047    * element is given.
0048    */
0049   virtual unsigned int orderInGs() const { return 1; }
0050
0051   /**
0052    * Return the (tree-level) order in \f$g_{EM}\f$ in which this matrix
0053    * element is given.
0054    */
0055   virtual unsigned int orderInGem() const { return 2; }
0056
0057   /**
0058    * Return true, if this amplitude is capable of calculating one-loop
0059    * (QCD) corrections.
0060    */
0061   virtual bool haveOneLoop() const { return true; }
0062
0063   /**
0064    * Calculate the tree level amplitudes for the phasespace point
0065    * stored in lastXComb.
0066    */
0067   virtual void prepareAmplitudes(Ptr<MatchboxMEBase>::tcptr);
0068
0069   /**
0070    * Evaluate the amplitude for the given colour tensor id and
0071    * helicity assignment
0072    */
0073   virtual Complex evaluate(size_t, const vector<int>&, Complex&);
0074
0075   /**
0076    * Evaluate the amplitude for the given colour tensor id and
0077    * helicity assignment
0078    */
0079   virtual Complex evaluateOneLoop(size_t, const vector<int>&);
0080
0081   /**
0082    * Return true, if one loop corrections are given in the conventions
0083    * of BDK.
0084    */
0085   virtual bool isBDK() const { return true; }
0086
0087   /**
0088    * Return the value of the dimensional regularization
0089    * parameter. Note that renormalization scale dependence is fully
0090    * restored in DipoleIOperator.
0091    */
0092   virtual Energy2 mu2() const { return lastSHat(); }
0093
0094   /**
0095    * Flush all cashes.
0096    */
0097   virtual void flushCaches() {
0098     MatchboxCurrents::reset();
0099     MatchboxZGammaAmplitude::flushCaches();
0100   }
0101
0102 public:
0103
0104   /** @name Functions used by the persistent I/O system. */
0105   //@{
0106   /**
0107    * Function used to write out object persistently.
0108    * @param os the persistent output stream written to.
0109    */
0110   void persistentOutput(PersistentOStream & os) const;
0111
0112   /**
0113    * Function used to read in object persistently.
0114    * @param is the persistent input stream read from.
0115    * @param version the version number of the object when written.
0116    */
0117   void persistentInput(PersistentIStream & is, int version);
0118   //@}
0119
0120   /**
0121    * The standard Init function used to initialize the interfaces.
0122    * Called exactly once for each class by the class description system
0123    * before the main function starts or
0124    * when this class is dynamically loaded.
0125    */
0126   static void Init();
0127
0128 protected:
0129
0130   /** @name Clone Methods. */
0131   //@{
0132   /**
0133    * Make a simple clone of this object.
0134    * @return a pointer to the new object.
0135    */
0136   virtual IBPtr clone() const;
0137
0138   /** Make a clone of this object, possibly modifying the cloned object
0139    * to make it sane.
0140    * @return a pointer to the new object.
0141    */
0142   virtual IBPtr fullclone() const;
0143   //@}
0144
0145
0146 // If needed, insert declarations of virtual function defined in the
0147 // InterfacedBase class here (using ThePEG-interfaced-decl in Emacs).
0148
0149 protected:
0150
0151   /** @name Standard Interfaced functions. */
0152   //@{
0153   /**
0154    * Initialize this object after the setup phase before saving an
0155    * EventGenerator to disk.
0156    * @throws InitException if object could not be initialized properly.
0157    */
0158   virtual void doinit();
0159
0160   /**
0161    * Initialize this object. Called in the run phase just before
0162    * a run begins.
0163    */
0164   virtual void doinitrun();
0165   //@}
0166
0167 private:
0168
0169   /**
0170    * The assignment operator is private and must never be called.
0171    * In fact, it should not even be implemented.
0172    */
0173   MatchboxAmplitudellbarqqbarg & operator=(const MatchboxAmplitudellbarqqbarg &) = delete;
0174
0175 };
0176
0177 }
0178
0179 #endif /* Herwig_MatchboxAmplitudellbarqqbarg_H */