Line data    Source code

       1             : // HadronLevel.h is a part of the PYTHIA event generator.
       2             : // Copyright (C) 2015 Torbjorn Sjostrand.
       3             : // PYTHIA is licenced under the GNU GPL version 2, see COPYING for details.
       4             : // Please respect the MCnet Guidelines, see GUIDELINES for details.
       5             : 
       6             : // This file contains the main class for hadron-level generation.
       7             : // HadronLevel: handles administration of fragmentation and decay.
       8             : 
       9             : #ifndef Pythia8_HadronLevel_H
      10             : #define Pythia8_HadronLevel_H
      11             : 
      12             : #include "Pythia8/Basics.h"
      13             : #include "Pythia8/BoseEinstein.h"
      14             : #include "Pythia8/ColourTracing.h"
      15             : #include "Pythia8/Event.h"
      16             : #include "Pythia8/FragmentationFlavZpT.h"
      17             : #include "Pythia8/FragmentationSystems.h"
      18             : #include "Pythia8/HadronScatter.h"
      19             : #include "Pythia8/HiddenValleyFragmentation.h"
      20             : #include "Pythia8/Info.h"
      21             : #include "Pythia8/JunctionSplitting.h"
      22             : #include "Pythia8/MiniStringFragmentation.h"
      23             : #include "Pythia8/ParticleData.h"
      24             : #include "Pythia8/ParticleDecays.h"
      25             : #include "Pythia8/PythiaStdlib.h"
      26             : #include "Pythia8/RHadrons.h"
      27             : #include "Pythia8/Settings.h"
      28             : #include "Pythia8/StringFragmentation.h"
      29             : #include "Pythia8/TimeShower.h"
      30             : 
      31             : namespace Pythia8 {
      32             : 
      33             : //==========================================================================
      34             : 
      35             : // The HadronLevel class contains the top-level routines to generate
      36             : // the transition from the partonic to the hadronic stage of an event.
      37             : 
      38           0 : class HadronLevel {
      39             : 
      40             : public:
      41             : 
      42             :   // Constructor.
      43           0 :   HadronLevel() {}
      44             : 
      45             :   // Initialize HadronLevel classes as required.
      46             :   bool init(Info* infoPtrIn, Settings& settings,
      47             :     ParticleData* particleDataPtrIn, Rndm* rndmPtrIn,
      48             :     Couplings* couplingsPtrIn, TimeShower* timesDecPtr,
      49             :     RHadrons* rHadronsPtrIn, DecayHandler* decayHandlePtr,
      50             :     vector<int> handledParticles);
      51             : 
      52             :   // Get pointer to StringFlav instance (needed by BeamParticle).
      53           0 :   StringFlav* getStringFlavPtr() {return &flavSel;}
      54             : 
      55             :   // Generate the next event.
      56             :   bool next(Event& event);
      57             : 
      58             :   // Special routine to allow more decays if on/off switches changed.
      59             :   bool moreDecays(Event& event);
      60             : 
      61             : private:
      62             : 
      63             :   // Initialization data, read from Settings.
      64             :   bool   doHadronize, doDecay, doBoseEinstein, allowRH;
      65             :   double mStringMin, eNormJunction, widthSepBE;
      66             : 
      67             :   // Settings for hadron scattering --rjc
      68             :   bool   doHadronScatter, hsAfterDecay;
      69             : 
      70             :   // Pointer to various information on the generation.
      71             :   Info*         infoPtr;
      72             : 
      73             :   // Pointer to the particle data table.
      74             :   ParticleData* particleDataPtr;
      75             : 
      76             :   // Pointer to the random number generator.
      77             :   Rndm*         rndmPtr;
      78             : 
      79             :   // Pointers to Standard Model couplings.
      80             :   Couplings*    couplingsPtr;
      81             : 
      82             :   // Configuration of colour-singlet systems.
      83             :   ColConfig     colConfig;
      84             : 
      85             :   // Colour and mass information.
      86             :   vector<int>    iParton, iJunLegA, iJunLegB, iJunLegC,
      87             :                  iAntiLegA, iAntiLegB, iAntiLegC, iGluLeg;
      88             :   vector<double> m2Pair;
      89             : 
      90             :   // The generator class for normal string fragmentation.
      91             :   StringFragmentation stringFrag;
      92             : 
      93             :   // The generator class for special low-mass string fragmentation.
      94             :   MiniStringFragmentation ministringFrag;
      95             : 
      96             :   // The generator class for normal decays.
      97             :   ParticleDecays decays;
      98             : 
      99             :   // The generator class for hadron scattering --rjc
     100             :   HadronScatter hadronScatter;
     101             : 
     102             :   // The generator class for Bose-Einstein effects.
     103             :   BoseEinstein boseEinstein;
     104             : 
     105             :   // Classes for flavour, pT and z generation.
     106             :   StringFlav flavSel;
     107             :   StringPT   pTSel;
     108             :   StringZ    zSel;
     109             : 
     110             :   // Class for colour tracing.
     111             :   ColourTracing colTrace;
     112             : 
     113             :   // Junction splitting class.
     114             :   JunctionSplitting junctionSplitting;
     115             : 
     116             :   // The RHadrons class is used to fragment off and decay R-hadrons.
     117             :   RHadrons*  rHadronsPtr;
     118             : 
     119             :   // Special class for Hidden-Valley hadronization. Not always used.
     120             :   HiddenValleyFragmentation hiddenvalleyFrag;
     121             :   bool useHiddenValley;
     122             : 
     123             :   // Special case: colour-octet onium decays, to be done initially.
     124             :   bool decayOctetOnia(Event& event);
     125             : 
     126             :   // Trace colour flow in the event to form colour singlet subsystems.
     127             :   bool findSinglets(Event& event);
     128             : 
     129             : };
     130             : 
     131             : //==========================================================================
     132             : 
     133             : } // end namespace Pythia8
     134             : 
     135             : #endif // Pythia8_HadronLevel_H