Matchbox/Phasespace/FIMassiveInvertedTildeKinematics.h

0001 // -*- C++ -*-
0002 //
0003 // FIMassiveInvertedTildeKinematics.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_FIMassiveInvertedTildeKinematics_H
0010 #define HERWIG_FIMassiveInvertedTildeKinematics_H
0011 //
0012 // This is the declaration of the FIMassiveInvertedTildeKinematics class.
0013 //
0014
0015 #include "Herwig/MatrixElement/Matchbox/Phasespace/InvertedTildeKinematics.h"
0016
0017 namespace Herwig {
0018
0019 using namespace ThePEG;
0020
0021 /**
0022  * \ingroup Matchbox
0023  * \author Simon Platzer, Martin Stoll
0024  *
0025  * \brief FIMassiveInvertedTildeKinematics inverts the final-final tilde
0026  * kinematics.
0027  *
0028  */
0029 class FIMassiveInvertedTildeKinematics: public Herwig::InvertedTildeKinematics {
0030
0031 public:
0032
0033   /**
0034    * Perform the mapping of the tilde kinematics for the
0035    * last selected process and store all dimensionless
0036    * variables in the subtractionParameters() vector.
0037    * Return false, if the calculation of the real
0038    * kinematics was impossible for the selected configuration
0039    * and true on success.
0040    */
0041   virtual bool doMap(const double *);
0042
0043   /**
0044    * Return the pt associated to the last generated splitting.
0045    */
0046   virtual Energy lastPt() const;
0047
0048   /**
0049    * Return the momentum fraction associated to the last splitting.
0050    */
0051   virtual double lastZ() const;
0052
0053   /**
0054    * Return the upper bound on pt
0055    */
0056   virtual Energy ptMax() const;
0057
0058   /**
0059    * Given a pt, return the boundaries on z
0060    */
0061   virtual pair<double,double> zBounds(Energy pt, Energy hardPt = ZERO) const;
0062
0063 public:
0064
0065   /**
0066    * Triangular / Kallen function
0067    */
0068   template <class T>
0069   inline T rootOfKallen (T a, T b, T c) const {
0070     return sqrt( a*a + b*b + c*c - 2.*( a*b+a*c+b*c ) ); }
0071
0072 public:
0073
0074   /** @name Functions used by the persistent I/O system. */
0075   //@{
0076   /**
0077    * Function used to write out object persistently.
0078    * @param os the persistent output stream written to.
0079    */
0080   void persistentOutput(PersistentOStream & os) const;
0081
0082   /**
0083    * Function used to read in object persistently.
0084    * @param is the persistent input stream read from.
0085    * @param version the version number of the object when written.
0086    */
0087   void persistentInput(PersistentIStream & is, int version);
0088   //@}
0089
0090   /**
0091    * The standard Init function used to initialize the interfaces.
0092    * Called exactly once for each class by the class description system
0093    * before the main function starts or
0094    * when this class is dynamically loaded.
0095    */
0096   static void Init();
0097
0098 protected:
0099
0100   /** @name Clone Methods. */
0101   //@{
0102   /**
0103    * Make a simple clone of this object.
0104    * @return a pointer to the new object.
0105    */
0106   virtual IBPtr clone() const;
0107
0108   /** Make a clone of this object, possibly modifying the cloned object
0109    * to make it sane.
0110    * @return a pointer to the new object.
0111    */
0112   virtual IBPtr fullclone() const;
0113   //@}
0114
0115
0116 // If needed, insert declarations of virtual function defined in the
0117 // InterfacedBase class here (using ThePEG-interfaced-decl in Emacs).
0118
0119
0120 private:
0121
0122   /**
0123    * The assignment operator is private and must never be called.
0124    * In fact, it should not even be implemented.
0125    */
0126   FIMassiveInvertedTildeKinematics & operator=(const FIMassiveInvertedTildeKinematics &) = delete;
0127
0128 };
0129
0130 }
0131
0132 #endif /* HERWIG_FIMassiveInvertedTildeKinematics_H */