| 1 | //
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| 2 | // ********************************************************************
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| 3 | // * License and Disclaimer *
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| 4 | // * *
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| 5 | // * The Geant4 software is copyright of the Copyright Holders of *
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| 6 | // * the Geant4 Collaboration. It is provided under the terms and *
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| 7 | // * conditions of the Geant4 Software License, included in the file *
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| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These *
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| 9 | // * include a list of copyright holders. *
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| 10 | // * *
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| 11 | // * Neither the authors of this software system, nor their employing *
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| 12 | // * institutes,nor the agencies providing financial support for this *
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| 13 | // * work make any representation or warranty, express or implied, *
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| 14 | // * regarding this software system or assume any liability for its *
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| 15 | // * use. Please see the license in the file LICENSE and URL above *
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| 16 | // * for the full disclaimer and the limitation of liability. *
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| 17 | // * *
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| 18 | // * This code implementation is the result of the scientific and *
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| 19 | // * technical work of the GEANT4 collaboration. *
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| 20 | // * By using, copying, modifying or distributing the software (or *
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| 21 | // * any work based on the software) you agree to acknowledge its *
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| 22 | // * use in resulting scientific publications, and indicate your *
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| 23 | // * acceptance of all terms of the Geant4 Software license. *
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| 24 | // ********************************************************************
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| 25 | //
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| 26 | //
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| 27 | // $Id: G4VLongitudinalStringDecay.cc,v 1.13 2008/06/23 08:35:55 vuzhinsk Exp $
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| 28 | // GEANT4 tag $Name: geant4-09-02 $
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| 29 | //
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| 30 | // -----------------------------------------------------------------------------
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| 31 | // GEANT 4 class implementation file
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| 32 | //
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| 33 | // History: first implementation, Maxim Komogorov, 1-Jul-1998
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| 34 | // redesign Gunter Folger, August/September 2001
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| 35 | // -----------------------------------------------------------------------------
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| 36 | #include "G4ios.hh"
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| 37 | #include "Randomize.hh"
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| 38 | #include "G4VLongitudinalStringDecay.hh"
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| 39 | #include "G4FragmentingString.hh"
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| 40 |
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| 41 | #include "G4ParticleDefinition.hh"
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| 42 | #include "G4ParticleTypes.hh"
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| 43 | #include "G4ParticleChange.hh"
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| 44 | #include "G4VShortLivedParticle.hh"
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| 45 | #include "G4ShortLivedConstructor.hh"
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| 46 | #include "G4ParticleTable.hh"
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| 47 | #include "G4ShortLivedTable.hh"
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| 48 | #include "G4PhaseSpaceDecayChannel.hh"
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| 49 | #include "G4VDecayChannel.hh"
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| 50 | #include "G4DecayTable.hh"
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| 51 |
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| 52 | #include "G4DiQuarks.hh"
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| 53 | #include "G4Quarks.hh"
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| 54 | #include "G4Gluons.hh"
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| 55 |
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| 56 | //------------------------debug switches
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| 57 | //#define DEBUG_LightFragmentationTest 1
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| 58 |
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| 59 |
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| 60 | //********************************************************************************
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| 61 | // Constructors
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| 62 |
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| 63 | G4VLongitudinalStringDecay::G4VLongitudinalStringDecay()
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| 64 | {
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| 65 | MassCut = 0.35*GeV;
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| 66 | ClusterMass = 0.15*GeV;
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| 67 |
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| 68 | SmoothParam = 0.9;
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| 69 | StringLoopInterrupt = 1000;
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| 70 | ClusterLoopInterrupt = 500;
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| 71 |
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| 72 | // Changable Parameters below.
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| 73 |
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| 74 | SigmaQT = 0.5 * GeV;
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| 75 |
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| 76 | StrangeSuppress = 0.44; // 27 % strange quarks produced, ie. u:d:s=1:1:0.27
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| 77 | DiquarkSuppress = 0.07;
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| 78 | DiquarkBreakProb = 0.1;
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| 79 |
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| 80 | //... pspin_meson is probability to create vector meson
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| 81 | pspin_meson = 0.5;
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| 82 |
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| 83 | //... pspin_barion is probability to create 3/2 barion
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| 84 | pspin_barion = 0.5;
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| 85 |
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| 86 | //... vectorMesonMix[] is quark mixing parameters for vector mesons (Variable spin = 3)
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| 87 | vectorMesonMix.resize(6);
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| 88 | vectorMesonMix[0] = 0.5;
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| 89 | vectorMesonMix[1] = 0.0;
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| 90 | vectorMesonMix[2] = 0.5;
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| 91 | vectorMesonMix[3] = 0.0;
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| 92 | vectorMesonMix[4] = 1.0;
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| 93 | vectorMesonMix[5] = 1.0;
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| 94 |
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| 95 | //... scalarMesonMix[] is quark mixing parameters for scalar mesons (Variable spin=1)
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| 96 | scalarMesonMix.resize(6);
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| 97 | scalarMesonMix[0] = 0.5;
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| 98 | scalarMesonMix[1] = 0.25;
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| 99 | scalarMesonMix[2] = 0.5;
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| 100 | scalarMesonMix[3] = 0.25;
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| 101 | scalarMesonMix[4] = 1.0;
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| 102 | scalarMesonMix[5] = 0.5;
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| 103 |
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| 104 | // Parameters may be changed until the first fragmentation starts
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| 105 | PastInitPhase=false;
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| 106 | hadronizer = new G4HadronBuilder(pspin_meson,pspin_barion,
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| 107 | scalarMesonMix,vectorMesonMix);
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| 108 | Kappa = 1.0 * GeV/fermi;
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| 109 |
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| 110 |
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| 111 | }
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| 112 |
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| 113 |
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| 114 | G4VLongitudinalStringDecay::~G4VLongitudinalStringDecay()
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| 115 | {
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| 116 | delete hadronizer;
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| 117 | }
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| 118 |
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| 119 | //=============================================================================
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| 120 |
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| 121 | // Operators
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| 122 |
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| 123 | //const & G4VLongitudinalStringDecay::operator=(const G4VLongitudinalStringDecay &)
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| 124 | // {
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| 125 | // }
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| 126 |
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| 127 | //-----------------------------------------------------------------------------
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| 128 |
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| 129 | int G4VLongitudinalStringDecay::operator==(const G4VLongitudinalStringDecay &) const
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| 130 | {
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| 131 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::operator== forbidden");
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| 132 | return false;
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| 133 | }
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| 134 |
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| 135 | //-------------------------------------------------------------------------------------
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| 136 |
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| 137 | int G4VLongitudinalStringDecay::operator!=(const G4VLongitudinalStringDecay &) const
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| 138 | {
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| 139 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::operator!= forbidden");
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| 140 | return true;
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| 141 | }
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| 142 |
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| 143 | //***********************************************************************************
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| 144 |
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| 145 | // For changing Mass Cut used for selection of very small mass strings
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| 146 | void G4VLongitudinalStringDecay::SetMassCut(G4double aValue){MassCut=aValue;}
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| 147 |
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| 148 | //-----------------------------------------------------------------------------
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| 149 |
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| 150 | // For handling a string with very low mass
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| 151 |
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| 152 | G4KineticTrackVector* G4VLongitudinalStringDecay::LightFragmentationTest(const
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| 153 | G4ExcitedString * const string)
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| 154 | {
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| 155 | // Check string decay threshold
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| 156 |
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| 157 | G4KineticTrackVector * result=0; // return 0 when string exceeds the mass cut
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| 158 |
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| 159 | pDefPair hadrons((G4ParticleDefinition *)0,(G4ParticleDefinition *)0);
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| 160 |
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| 161 | G4FragmentingString aString(*string);
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| 162 |
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| 163 | if ( sqr(FragmentationMass(&aString,0,&hadrons)+MassCut) < aString.Mass2()) {
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| 164 | return 0;
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| 165 | }
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| 166 |
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| 167 | // The string mass is very low ---------------------------
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| 168 |
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| 169 | result=new G4KineticTrackVector;
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| 170 |
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| 171 | if ( hadrons.second ==0 )
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| 172 | {
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| 173 | // Substitute string by light hadron, Note that Energy is not conserved here!
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| 174 |
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| 175 | /*
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| 176 | #ifdef DEBUG_LightFragmentationTest
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| 177 | G4cout << "VlongSF Warning replacing string by single hadron " <<G4endl;
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| 178 | G4cout << hadrons.first->GetParticleName()
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| 179 | << "string .. " << string->Get4Momentum() << " "
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| 180 | << string->Get4Momentum().m() << G4endl;
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| 181 | #endif
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| 182 | G4cout << "VlongSF Warning replacing string by single hadron " <<G4endl;
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| 183 | G4cout << hadrons.first->GetParticleName() << " string .. " <<G4endl;
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| 184 | G4cout << string->Get4Momentum() << " " << string->Get4Momentum().m() << G4endl;
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| 185 | */
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| 186 | G4ThreeVector Mom3 = string->Get4Momentum().vect();
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| 187 | G4LorentzVector Mom(Mom3,
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| 188 | std::sqrt(Mom3.mag2() +
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| 189 | sqr(hadrons.first->GetPDGMass())));
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| 190 | result->push_back(new G4KineticTrack(hadrons.first, 0,
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| 191 | string->GetPosition(),
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| 192 | Mom));
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| 193 | } else
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| 194 | {
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| 195 | //... string was qq--qqbar type: Build two stable hadrons,
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| 196 |
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| 197 | #ifdef DEBUG_LightFragmentationTest
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| 198 | G4cout << "VlongSF Warning replacing qq-qqbar string by TWO hadrons "
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| 199 | << hadrons.first->GetParticleName() << " / "
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| 200 | << hadrons.second->GetParticleName()
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| 201 | << "string .. " << string->Get4Momentum() << " "
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| 202 | << string->Get4Momentum().m() << G4endl;
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| 203 | #endif
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| 204 |
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| 205 | // Uzhi Formation time in the case???
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| 206 |
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| 207 | G4LorentzVector Mom1, Mom2;
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| 208 | Sample4Momentum(&Mom1, hadrons.first->GetPDGMass(),
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| 209 | &Mom2,hadrons.second->GetPDGMass(),
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| 210 | string->Get4Momentum().mag());
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| 211 |
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| 212 | result->push_back(new G4KineticTrack(hadrons.first, 0,
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| 213 | string->GetPosition(),
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| 214 | Mom1));
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| 215 | result->push_back(new G4KineticTrack(hadrons.second, 0,
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| 216 | string->GetPosition(),
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| 217 | Mom2));
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| 218 |
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| 219 | G4ThreeVector Velocity = string->Get4Momentum().boostVector();
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| 220 | result->Boost(Velocity);
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| 221 | }
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| 222 |
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| 223 | return result;
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| 224 |
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| 225 | }
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| 226 |
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| 227 | //----------------------------------------------------------------------------------------
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| 228 |
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| 229 | G4double G4VLongitudinalStringDecay::FragmentationMass(
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| 230 | const G4FragmentingString * const string,
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| 231 | Pcreate build, pDefPair * pdefs )
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| 232 | {
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| 233 |
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| 234 | G4double mass;
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| 235 | static G4bool NeedInit(true);
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| 236 | static std::vector<double> nomix;
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| 237 | static G4HadronBuilder * minMassHadronizer;
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| 238 | if ( NeedInit )
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| 239 | {
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| 240 | NeedInit = false;
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| 241 | nomix.resize(6);
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| 242 | for ( G4int i=0; i<6 ; i++ ) nomix[i]=0;
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| 243 |
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| 244 | // minMassHadronizer=new G4HadronBuilder(pspin_meson,pspin_barion,nomix,nomix);
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| 245 | minMassHadronizer=hadronizer;
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| 246 | }
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| 247 |
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| 248 | if ( build==0 ) build=&G4HadronBuilder::BuildLowSpin;
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| 249 |
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| 250 | G4ParticleDefinition *Hadron1, *Hadron2=0;
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| 251 |
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| 252 | if (!string->FourQuarkString() )
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| 253 | {
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| 254 | // spin 0 meson or spin 1/2 barion will be built
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| 255 |
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| 256 | Hadron1 = (minMassHadronizer->*build)(string->GetLeftParton(),
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| 257 | string->GetRightParton());
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| 258 | mass= (Hadron1)->GetPDGMass();
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| 259 | } else
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| 260 | {
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| 261 | //... string is qq--qqbar: Build two stable hadrons,
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| 262 | //... with extra uubar or ddbar quark pair
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| 263 | G4int iflc = (G4UniformRand() < 0.5)? 1 : 2;
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| 264 | if (string->GetLeftParton()->GetPDGEncoding() < 0) iflc = -iflc;
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| 265 |
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| 266 | //... theSpin = 4; spin 3/2 baryons will be built
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| 267 | Hadron1 = (minMassHadronizer->*build)(string->GetLeftParton(),
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| 268 | FindParticle(iflc) );
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| 269 | Hadron2 = (minMassHadronizer->*build)(string->GetRightParton(),
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| 270 | FindParticle(-iflc) );
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| 271 | mass = (Hadron1)->GetPDGMass() + (Hadron2)->GetPDGMass();
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| 272 | }
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| 273 |
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| 274 | if ( pdefs != 0 )
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| 275 | { // need to return hadrons as well....
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| 276 | pdefs->first = Hadron1;
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| 277 | pdefs->second = Hadron2;
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| 278 | }
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| 279 |
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| 280 | return mass;
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| 281 | }
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| 282 |
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| 283 | //----------------------------------------------------------------------------
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| 284 |
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| 285 | G4ParticleDefinition* G4VLongitudinalStringDecay::FindParticle(G4int Encoding)
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| 286 | {
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| 287 | G4ParticleDefinition* ptr = G4ParticleTable::GetParticleTable()->FindParticle(Encoding);
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| 288 | if (ptr == NULL)
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| 289 | {
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| 290 | G4cout << "Particle with encoding "<<Encoding<<" does not exist!!!"<<G4endl;
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| 291 | throw G4HadronicException(__FILE__, __LINE__, "Check your particle table");
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| 292 | }
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| 293 | return ptr;
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| 294 | }
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| 295 |
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| 296 | //-----------------------------------------------------------------------------
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| 297 | // virtual void Sample4Momentum(G4LorentzVector* Mom, G4double Mass,
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| 298 | // G4LorentzVector* AntiMom, G4double AntiMass,
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| 299 | // G4double InitialMass)=0;
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| 300 | //-----------------------------------------------------------------------------
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| 301 |
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| 302 | //*********************************************************************************
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| 303 | // For decision on continue or stop string fragmentation
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| 304 | // virtual G4bool StopFragmenting(const G4FragmentingString * const string)=0;
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| 305 | // virtual G4bool IsFragmentable(const G4FragmentingString * const string)=0;
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| 306 |
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| 307 | // If a string can not fragment, make last break into 2 hadrons
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| 308 | // virtual G4bool SplitLast(G4FragmentingString * string,
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| 309 | // G4KineticTrackVector * LeftVector,
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| 310 | // G4KineticTrackVector * RightVector)=0;
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| 311 | //-----------------------------------------------------------------------------
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| 312 | //
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| 313 | // If a string fragments, do the following
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| 314 | //
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| 315 | // For transver of a string to its CMS frame
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| 316 | //-----------------------------------------------------------------------------
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| 317 |
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| 318 | G4ExcitedString *G4VLongitudinalStringDecay::CPExcited(const G4ExcitedString & in)
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| 319 | {
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| 320 | G4Parton *Left=new G4Parton(*in.GetLeftParton());
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| 321 | G4Parton *Right=new G4Parton(*in.GetRightParton());
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| 322 | return new G4ExcitedString(Left,Right,in.GetDirection());
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| 323 | }
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| 324 |
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| 325 | //-----------------------------------------------------------------------------
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| 326 |
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| 327 | G4KineticTrack * G4VLongitudinalStringDecay::Splitup(
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| 328 | G4FragmentingString *string,
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| 329 | G4FragmentingString *&newString)
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| 330 | {
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| 331 | //G4cout<<"In G4VLong String Dec######################"<<G4endl;
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| 332 |
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| 333 | //... random choice of string end to use for creating the hadron (decay)
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| 334 | SideOfDecay = (G4UniformRand() < 0.5)? 1: -1;
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| 335 | if (SideOfDecay < 0)
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| 336 | {
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| 337 | string->SetLeftPartonStable();
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| 338 | } else
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| 339 | {
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| 340 | string->SetRightPartonStable();
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| 341 | }
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| 342 |
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| 343 | G4ParticleDefinition *newStringEnd;
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| 344 | G4ParticleDefinition * HadronDefinition;
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| 345 | if (string->DecayIsQuark())
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| 346 | {
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| 347 | HadronDefinition= QuarkSplitup(string->GetDecayParton(), newStringEnd);
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| 348 | } else {
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| 349 | HadronDefinition= DiQuarkSplitup(string->GetDecayParton(), newStringEnd);
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| 350 | }
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| 351 | // create new String from old, ie. keep Left and Right order, but replace decay
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| 352 |
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| 353 | newString=new G4FragmentingString(*string,newStringEnd); // To store possible
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| 354 | // quark containt of new string
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| 355 | G4LorentzVector* HadronMomentum=SplitEandP(HadronDefinition, string, newString);
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| 356 |
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| 357 | delete newString; newString=0; // Uzhi 20.06.08
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| 358 |
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| 359 | G4KineticTrack * Hadron =0;
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| 360 | if ( HadronMomentum != 0 ) {
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| 361 |
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| 362 | G4ThreeVector Pos;
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| 363 | Hadron = new G4KineticTrack(HadronDefinition, 0,Pos, *HadronMomentum);
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| 364 |
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| 365 | newString=new G4FragmentingString(*string,newStringEnd,
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| 366 | HadronMomentum);
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| 367 |
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| 368 | //G4cout<<"Out G4VLong String Dec######################"<<G4endl;
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| 369 | //G4cout<<"newString 4Mom"<<newString->Get4Momentum()<<G4endl;
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| 370 | //G4cout<<"newString Pl "<<newString->LightConePlus()<<G4endl;
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| 371 | //G4cout<<"newString Mi "<<newString->LightConeMinus()<<G4endl;
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| 372 | //G4cout<<"newString Pts "<<newString->StablePt()<<G4endl;
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| 373 | //G4cout<<"newString Ptd "<<newString->DecayPt()<<G4endl;
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| 374 | //G4cout<<"newString M2 "<<newString->Mass2()<<G4endl;
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| 375 | //G4cout<<"newString M2 "<<newString->Mass()<<G4endl;
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| 376 | delete HadronMomentum;
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| 377 | }
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| 378 | return Hadron;
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| 379 | }
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| 380 |
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| 381 | //--------------------------------------------------------------------------------------
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| 382 |
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| 383 | G4ParticleDefinition *
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| 384 | G4VLongitudinalStringDecay::QuarkSplitup(G4ParticleDefinition*
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| 385 | decay, G4ParticleDefinition *&created)
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| 386 | {
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| 387 | G4int IsParticle=(decay->GetPDGEncoding()>0) ? -1 : +1; // if we have a quark,
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| 388 | // we need antiquark
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| 389 | // (or diquark)
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| 390 | pDefPair QuarkPair = CreatePartonPair(IsParticle);
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| 391 | created = QuarkPair.second;
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| 392 | return hadronizer->Build(QuarkPair.first, decay);
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| 393 |
|
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| 394 | }
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| 395 |
|
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| 396 | //-----------------------------------------------------------------------------
|
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| 397 |
|
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| 398 | G4ParticleDefinition *G4VLongitudinalStringDecay::DiQuarkSplitup(
|
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| 399 | G4ParticleDefinition* decay,
|
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| 400 | G4ParticleDefinition *&created)
|
|---|
| 401 | {
|
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| 402 | //... can Diquark break or not?
|
|---|
| 403 | if (G4UniformRand() < DiquarkBreakProb ){
|
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| 404 | //... Diquark break
|
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| 405 |
|
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| 406 | G4int stableQuarkEncoding = decay->GetPDGEncoding()/1000;
|
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| 407 | G4int decayQuarkEncoding = (decay->GetPDGEncoding()/100)%10;
|
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| 408 | if (G4UniformRand() < 0.5)
|
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| 409 | {
|
|---|
| 410 | G4int Swap = stableQuarkEncoding;
|
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| 411 | stableQuarkEncoding = decayQuarkEncoding;
|
|---|
| 412 | decayQuarkEncoding = Swap;
|
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| 413 | }
|
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| 414 |
|
|---|
| 415 | G4int IsParticle=(decayQuarkEncoding>0) ? -1 : +1;
|
|---|
| 416 | // if we have a quark, we need antiquark)
|
|---|
| 417 | pDefPair QuarkPair = CreatePartonPair(IsParticle,false); // no diquarks wanted
|
|---|
| 418 | //... Build new Diquark
|
|---|
| 419 | G4int QuarkEncoding=QuarkPair.second->GetPDGEncoding();
|
|---|
| 420 | G4int i10 = std::max(std::abs(QuarkEncoding), std::abs(stableQuarkEncoding));
|
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| 421 | G4int i20 = std::min(std::abs(QuarkEncoding), std::abs(stableQuarkEncoding));
|
|---|
| 422 | G4int spin = (i10 != i20 && G4UniformRand() <= 0.5)? 1 : 3;
|
|---|
| 423 | G4int NewDecayEncoding = -1*IsParticle*(i10 * 1000 + i20 * 100 + spin);
|
|---|
| 424 | created = FindParticle(NewDecayEncoding);
|
|---|
| 425 | G4ParticleDefinition * decayQuark=FindParticle(decayQuarkEncoding);
|
|---|
| 426 | G4ParticleDefinition * had=hadronizer->Build(QuarkPair.first, decayQuark);
|
|---|
| 427 | return had;
|
|---|
| 428 | // return hadronizer->Build(QuarkPair.first, decayQuark);
|
|---|
| 429 |
|
|---|
| 430 | } else {
|
|---|
| 431 | //... Diquark does not break
|
|---|
| 432 |
|
|---|
| 433 | G4int IsParticle=(decay->GetPDGEncoding()>0) ? +1 : -1;
|
|---|
| 434 | // if we have a diquark, we need quark)
|
|---|
| 435 | pDefPair QuarkPair = CreatePartonPair(IsParticle,false); // no diquarks wanted
|
|---|
| 436 | created = QuarkPair.second;
|
|---|
| 437 |
|
|---|
| 438 | G4ParticleDefinition * had=hadronizer->Build(QuarkPair.first, decay);
|
|---|
| 439 | return had;
|
|---|
| 440 | // return G4ParticleDefinition * had=hadronizer->Build(QuarkPair.first, decay);
|
|---|
| 441 | }
|
|---|
| 442 | }
|
|---|
| 443 |
|
|---|
| 444 | //-----------------------------------------------------------------------------
|
|---|
| 445 |
|
|---|
| 446 | G4int G4VLongitudinalStringDecay::SampleQuarkFlavor(void)
|
|---|
| 447 | {
|
|---|
| 448 | return (1 + (int)(G4UniformRand()/StrangeSuppress));
|
|---|
| 449 | }
|
|---|
| 450 |
|
|---|
| 451 | //-----------------------------------------------------------------------------
|
|---|
| 452 |
|
|---|
| 453 | G4VLongitudinalStringDecay::pDefPair G4VLongitudinalStringDecay::CreatePartonPair(G4int NeedParticle,G4bool AllowDiquarks)
|
|---|
| 454 | {
|
|---|
| 455 | // NeedParticle = +1 for Particle, -1 for Antiparticle
|
|---|
| 456 |
|
|---|
| 457 | if ( AllowDiquarks && G4UniformRand() < DiquarkSuppress )
|
|---|
| 458 | {
|
|---|
| 459 | // Create a Diquark - AntiDiquark pair , first in pair is anti to IsParticle
|
|---|
| 460 | G4int q1 = SampleQuarkFlavor();
|
|---|
| 461 | G4int q2 = SampleQuarkFlavor();
|
|---|
| 462 | G4int spin = (q1 != q2 && G4UniformRand() <= 0.5)? 1 : 3;
|
|---|
| 463 | // convention: quark with higher PDG number is first
|
|---|
| 464 | G4int PDGcode = (std::max(q1,q2) * 1000 + std::min(q1,q2) * 100 + spin) * NeedParticle;
|
|---|
| 465 | return pDefPair (FindParticle(-PDGcode),FindParticle(PDGcode));
|
|---|
| 466 |
|
|---|
| 467 |
|
|---|
| 468 | } else {
|
|---|
| 469 | // Create a Quark - AntiQuark pair, first in pair IsParticle
|
|---|
| 470 | G4int PDGcode=SampleQuarkFlavor()*NeedParticle;
|
|---|
| 471 | return pDefPair (FindParticle(PDGcode),FindParticle(-PDGcode));
|
|---|
| 472 | }
|
|---|
| 473 |
|
|---|
| 474 | }
|
|---|
| 475 |
|
|---|
| 476 | //-----------------------------------------------------------------------------
|
|---|
| 477 |
|
|---|
| 478 | // G4ThreeVector G4VLongitudinalStringDecay::SampleQuarkPt()
|
|---|
| 479 | // {
|
|---|
| 480 | // G4double width_param= 2.0 * GeV*GeV;
|
|---|
| 481 | // G4double R = G4UniformRand();
|
|---|
| 482 | // G4double Pt = std::sqrt(width_param*R/(1-R));
|
|---|
| 483 | // G4double phi = 2.*pi*G4UniformRand();
|
|---|
| 484 | // return G4ThreeVector(Pt * std::cos(phi),Pt * std::sin(phi),0);
|
|---|
| 485 | // }
|
|---|
| 486 |
|
|---|
| 487 | G4ThreeVector G4VLongitudinalStringDecay::SampleQuarkPt()
|
|---|
| 488 | {
|
|---|
| 489 | G4double Pt = -std::log(G4UniformRand());
|
|---|
| 490 | Pt = SigmaQT * std::sqrt(Pt);
|
|---|
| 491 | G4double phi = 2.*pi*G4UniformRand();
|
|---|
| 492 | return G4ThreeVector(Pt * std::cos(phi),Pt * std::sin(phi),0);
|
|---|
| 493 | }
|
|---|
| 494 |
|
|---|
| 495 | //******************************************************************************
|
|---|
| 496 |
|
|---|
| 497 | void G4VLongitudinalStringDecay::CalculateHadronTimePosition(G4double theInitialStringMass, G4KineticTrackVector* Hadrons)
|
|---|
| 498 | {
|
|---|
| 499 |
|
|---|
| 500 | // `yo-yo` formation time
|
|---|
| 501 | // const G4double kappa = 1.0 * GeV/fermi/4.; // Uzhi String tension 1.06.08
|
|---|
| 502 | G4double kappa = GetStringTensionParameter();
|
|---|
| 503 | //G4cout<<"Kappa "<<kappa<<G4endl; // Uzhi 20.06.08
|
|---|
| 504 | //G4int Uzhi; G4cin>>Uzhi; // Uzhi 20.06.08
|
|---|
| 505 | for(size_t c1 = 0; c1 < Hadrons->size(); c1++)
|
|---|
| 506 | {
|
|---|
| 507 | G4double SumPz = 0;
|
|---|
| 508 | G4double SumE = 0;
|
|---|
| 509 | for(size_t c2 = 0; c2 < c1; c2++)
|
|---|
| 510 | {
|
|---|
| 511 | SumPz += Hadrons->operator[](c2)->Get4Momentum().pz();
|
|---|
| 512 | SumE += Hadrons->operator[](c2)->Get4Momentum().e();
|
|---|
| 513 | }
|
|---|
| 514 | G4double HadronE = Hadrons->operator[](c1)->Get4Momentum().e();
|
|---|
| 515 | G4double HadronPz = Hadrons->operator[](c1)->Get4Momentum().pz();
|
|---|
| 516 | Hadrons->operator[](c1)->SetFormationTime((theInitialStringMass - 2.*SumPz + HadronE - HadronPz)/(2.*kappa));
|
|---|
| 517 | G4ThreeVector aPosition(0, 0, (theInitialStringMass - 2.*SumE - HadronE + HadronPz)/(2.*kappa));
|
|---|
| 518 | Hadrons->operator[](c1)->SetPosition(aPosition);
|
|---|
| 519 | }
|
|---|
| 520 | }
|
|---|
| 521 |
|
|---|
| 522 | //-----------------------------------------------------------------------------
|
|---|
| 523 |
|
|---|
| 524 | /*
|
|---|
| 525 | void G4VLongitudinalStringDecay::CalculateHadronTimePosition(G4double theInitialStringMass, G4KineticTrackVector* Hadrons)
|
|---|
| 526 | {
|
|---|
| 527 | // 'constituent' formation time
|
|---|
| 528 | const G4double kappa = 1.0 * GeV/fermi;
|
|---|
| 529 | for(G4int c1 = 0; c1 < Hadrons->length(); c1++)
|
|---|
| 530 | {
|
|---|
| 531 | G4double SumPz = 0;
|
|---|
| 532 | G4double SumE = 0;
|
|---|
| 533 | for(G4int c2 = 0; c2 <= c1; c2++)
|
|---|
| 534 | {
|
|---|
| 535 | SumPz += Hadrons->at(c2)->Get4Momentum().pz();
|
|---|
| 536 | SumE += Hadrons->at(c2)->Get4Momentum().e();
|
|---|
| 537 | }
|
|---|
| 538 | Hadrons->at(c1)->SetFormationTime((theInitialStringMass - 2.*SumPz)/(2.*kappa));
|
|---|
| 539 | G4ThreeVector aPosition(0, 0, (theInitialStringMass - 2.*SumE)/(2.*kappa));
|
|---|
| 540 | Hadrons->at(c1)->SetPosition(aPosition);
|
|---|
| 541 | }
|
|---|
| 542 | c1 = Hadrons->length()-1;
|
|---|
| 543 | Hadrons->at(c1)->SetFormationTime(Hadrons->at(c1-1)->GetFormationTime());
|
|---|
| 544 | Hadrons->at(c1)->SetPosition(Hadrons->at(c1-1)->GetPosition());
|
|---|
| 545 | }
|
|---|
| 546 | */
|
|---|
| 547 |
|
|---|
| 548 |
|
|---|
| 549 | //*****************************************************************************
|
|---|
| 550 |
|
|---|
| 551 | void G4VLongitudinalStringDecay::SetSigmaTransverseMomentum(G4double aValue)
|
|---|
| 552 | {
|
|---|
| 553 | if ( PastInitPhase ) {
|
|---|
| 554 | throw G4HadronicException(__FILE__, __LINE__, "4VLongitudinalStringDecay::SetSigmaTransverseMomentum after FragmentString() not allowed");
|
|---|
| 555 | } else {
|
|---|
| 556 | SigmaQT = aValue;
|
|---|
| 557 | }
|
|---|
| 558 | }
|
|---|
| 559 |
|
|---|
| 560 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 561 |
|
|---|
| 562 | void G4VLongitudinalStringDecay::SetStrangenessSuppression(G4double aValue)
|
|---|
| 563 | {
|
|---|
| 564 | if ( PastInitPhase ) {
|
|---|
| 565 | throw G4HadronicException(__FILE__, __LINE__, "4VLongitudinalStringDecay::SetStrangenessSuppression after FragmentString() not allowed");
|
|---|
| 566 | } else {
|
|---|
| 567 | StrangeSuppress = aValue;
|
|---|
| 568 | }
|
|---|
| 569 | }
|
|---|
| 570 |
|
|---|
| 571 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 572 |
|
|---|
| 573 | void G4VLongitudinalStringDecay::SetDiquarkSuppression(G4double aValue)
|
|---|
| 574 | {
|
|---|
| 575 | if ( PastInitPhase ) {
|
|---|
| 576 | throw G4HadronicException(__FILE__, __LINE__, "4VLongitudinalStringDecay::SetDiquarkSuppression after FragmentString() not allowed");
|
|---|
| 577 | } else {
|
|---|
| 578 | DiquarkSuppress = aValue;
|
|---|
| 579 | }
|
|---|
| 580 | }
|
|---|
| 581 |
|
|---|
| 582 | //----------------------------------------------------------------------------------------
|
|---|
| 583 |
|
|---|
| 584 | void G4VLongitudinalStringDecay::SetDiquarkBreakProbability(G4double aValue)
|
|---|
| 585 | {
|
|---|
| 586 | if ( PastInitPhase ) {
|
|---|
| 587 | throw G4HadronicException(__FILE__, __LINE__, "4VLongitudinalStringDecay::SetDiquarkBreakProbability after FragmentString() not allowed");
|
|---|
| 588 | } else {
|
|---|
| 589 | DiquarkBreakProb = aValue;
|
|---|
| 590 | }
|
|---|
| 591 | }
|
|---|
| 592 |
|
|---|
| 593 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 594 |
|
|---|
| 595 | void G4VLongitudinalStringDecay::SetVectorMesonProbability(G4double aValue)
|
|---|
| 596 | {
|
|---|
| 597 | if ( PastInitPhase ) {
|
|---|
| 598 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetVectorMesonProbability after FragmentString() not allowed");
|
|---|
| 599 | } else {
|
|---|
| 600 | pspin_meson = aValue;
|
|---|
| 601 | delete hadronizer;
|
|---|
| 602 | hadronizer = new G4HadronBuilder(pspin_meson,pspin_barion,
|
|---|
| 603 | scalarMesonMix,vectorMesonMix);
|
|---|
| 604 | }
|
|---|
| 605 | }
|
|---|
| 606 |
|
|---|
| 607 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 608 |
|
|---|
| 609 | void G4VLongitudinalStringDecay::SetSpinThreeHalfBarionProbability(G4double aValue)
|
|---|
| 610 | {
|
|---|
| 611 | if ( PastInitPhase ) {
|
|---|
| 612 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetSpinThreeHalfBarionProbability after FragmentString() not allowed");
|
|---|
| 613 | } else {
|
|---|
| 614 | pspin_barion = aValue;
|
|---|
| 615 | delete hadronizer;
|
|---|
| 616 | hadronizer = new G4HadronBuilder(pspin_meson,pspin_barion,
|
|---|
| 617 | scalarMesonMix,vectorMesonMix);
|
|---|
| 618 | }
|
|---|
| 619 | }
|
|---|
| 620 |
|
|---|
| 621 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 622 |
|
|---|
| 623 | void G4VLongitudinalStringDecay::SetScalarMesonMixings(std::vector<G4double> aVector)
|
|---|
| 624 | {
|
|---|
| 625 | if ( PastInitPhase ) {
|
|---|
| 626 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetScalarMesonMixings after FragmentString() not allowed");
|
|---|
| 627 | } else {
|
|---|
| 628 | if ( aVector.size() < 6 )
|
|---|
| 629 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetScalarMesonMixings( argument Vector too small");
|
|---|
| 630 | scalarMesonMix[0] = aVector[0];
|
|---|
| 631 | scalarMesonMix[1] = aVector[1];
|
|---|
| 632 | scalarMesonMix[2] = aVector[2];
|
|---|
| 633 | scalarMesonMix[3] = aVector[3];
|
|---|
| 634 | scalarMesonMix[4] = aVector[4];
|
|---|
| 635 | scalarMesonMix[5] = aVector[5];
|
|---|
| 636 | delete hadronizer;
|
|---|
| 637 | hadronizer = new G4HadronBuilder(pspin_meson,pspin_barion,
|
|---|
| 638 | scalarMesonMix,vectorMesonMix);
|
|---|
| 639 | }
|
|---|
| 640 | }
|
|---|
| 641 |
|
|---|
| 642 | //----------------------------------------------------------------------------------------------------------
|
|---|
| 643 |
|
|---|
| 644 | void G4VLongitudinalStringDecay::SetVectorMesonMixings(std::vector<G4double> aVector)
|
|---|
| 645 | {
|
|---|
| 646 | if ( PastInitPhase ) {
|
|---|
| 647 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetVectorMesonMixings after FragmentString() not allowed");
|
|---|
| 648 | } else {
|
|---|
| 649 | if ( aVector.size() < 6 )
|
|---|
| 650 | throw G4HadronicException(__FILE__, __LINE__, "G4VLongitudinalStringDecay::SetVectorMesonMixings( argument Vector too small");
|
|---|
| 651 | vectorMesonMix[0] = aVector[0];
|
|---|
| 652 | vectorMesonMix[1] = aVector[1];
|
|---|
| 653 | vectorMesonMix[2] = aVector[2];
|
|---|
| 654 | vectorMesonMix[3] = aVector[3];
|
|---|
| 655 | vectorMesonMix[4] = aVector[4];
|
|---|
| 656 | vectorMesonMix[5] = aVector[5];
|
|---|
| 657 | delete hadronizer;
|
|---|
| 658 | hadronizer = new G4HadronBuilder(pspin_meson,pspin_barion,
|
|---|
| 659 | scalarMesonMix,vectorMesonMix);
|
|---|
| 660 |
|
|---|
| 661 | }
|
|---|
| 662 | }
|
|---|
| 663 |
|
|---|
| 664 | //-------------------------------------------------------------------------------------------
|
|---|
| 665 | void G4VLongitudinalStringDecay::SetStringTensionParameter(G4double aValue)// Uzhi 20 June 08
|
|---|
| 666 | {
|
|---|
| 667 | Kappa = aValue * GeV/fermi;
|
|---|
| 668 | }
|
|---|
| 669 | //**************************************************************************************
|
|---|
| 670 |
|
|---|