[819] | 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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[962] | 27 | // $Id: G4StatMFChannel.cc,v 1.10 2008/11/19 14:33:31 vnivanch Exp $ |
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[1228] | 28 | // GEANT4 tag $Name: geant4-09-03 $ |
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[819] | 29 | // |
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| 30 | // Hadronic Process: Nuclear De-excitations |
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| 31 | // by V. Lara |
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[962] | 32 | // |
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| 33 | // Modified: |
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| 34 | // 25.07.08 I.Pshenichnov (in collaboration with Alexander Botvina and Igor |
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| 35 | // Mishustin (FIAS, Frankfurt, INR, Moscow and Kurchatov Institute, |
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| 36 | // Moscow, pshenich@fias.uni-frankfurt.de) fixed semi-infinite loop |
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[819] | 37 | |
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[962] | 38 | |
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[819] | 39 | #include "G4StatMFChannel.hh" |
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| 40 | #include "G4HadronicException.hh" |
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| 41 | #include <numeric> |
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| 42 | |
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| 43 | class SumCoulombEnergy : public std::binary_function<G4double,G4double,G4double> |
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| 44 | { |
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| 45 | public: |
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| 46 | SumCoulombEnergy() : total(0.0) {} |
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| 47 | G4double operator() (G4double& , G4StatMFFragment*& frag) |
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| 48 | { |
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| 49 | total += frag->GetCoulombEnergy(); |
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| 50 | return total; |
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| 51 | } |
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| 52 | |
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| 53 | G4double GetTotal() { return total; } |
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| 54 | public: |
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| 55 | G4double total; |
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| 56 | }; |
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| 57 | |
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| 58 | |
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| 59 | |
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| 60 | |
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| 61 | |
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| 62 | // Copy constructor |
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| 63 | G4StatMFChannel::G4StatMFChannel(const G4StatMFChannel & ) |
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| 64 | { |
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| 65 | throw G4HadronicException(__FILE__, __LINE__, "G4StatMFChannel::copy_constructor meant to not be accessable"); |
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| 66 | } |
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| 67 | |
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| 68 | // Operators |
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| 69 | |
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| 70 | G4StatMFChannel & G4StatMFChannel:: |
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| 71 | operator=(const G4StatMFChannel & ) |
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| 72 | { |
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| 73 | throw G4HadronicException(__FILE__, __LINE__, "G4StatMFChannel::operator= meant to not be accessable"); |
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| 74 | return *this; |
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| 75 | } |
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| 76 | |
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| 77 | |
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| 78 | G4bool G4StatMFChannel::operator==(const G4StatMFChannel & ) const |
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| 79 | { |
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| 80 | // throw G4HadronicException(__FILE__, __LINE__, "G4StatMFChannel::operator== meant to not be accessable"); |
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| 81 | return false; |
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| 82 | } |
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| 83 | |
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| 84 | |
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| 85 | G4bool G4StatMFChannel::operator!=(const G4StatMFChannel & ) const |
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| 86 | { |
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| 87 | // throw G4HadronicException(__FILE__, __LINE__, "G4StatMFChannel::operator!= meant to not be accessable"); |
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| 88 | return true; |
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| 89 | } |
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| 90 | |
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| 91 | |
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| 92 | G4bool G4StatMFChannel::CheckFragments(void) |
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| 93 | { |
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| 94 | std::deque<G4StatMFFragment*>::iterator i; |
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| 95 | for (i = _theFragments.begin(); |
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| 96 | i != _theFragments.end(); ++i) |
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| 97 | { |
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| 98 | G4int A = static_cast<G4int>((*i)->GetA()); |
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| 99 | G4int Z = static_cast<G4int>((*i)->GetZ()); |
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[962] | 100 | if ( (A > 1 && (Z > A || Z <= 0)) || (A==1 && Z > A) || A <= 0 ) return false; |
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[819] | 101 | } |
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| 102 | |
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| 103 | return true; |
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| 104 | } |
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| 105 | |
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| 106 | |
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| 107 | |
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| 108 | |
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| 109 | void G4StatMFChannel::CreateFragment(const G4double A, const G4double Z) |
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| 110 | // Create a new fragment. |
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| 111 | // Fragments are automatically sorted: first charged fragments, |
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| 112 | // then neutral ones. |
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| 113 | { |
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| 114 | if (Z <= 0.5) { |
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| 115 | _theFragments.push_back(new G4StatMFFragment(static_cast<G4int>(A),static_cast<G4int>(Z))); |
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| 116 | _NumOfNeutralFragments++; |
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| 117 | } else { |
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| 118 | _theFragments.push_front(new G4StatMFFragment(static_cast<G4int>(A),static_cast<G4int>(Z))); |
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| 119 | _NumOfChargedFragments++; |
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| 120 | } |
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| 121 | |
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| 122 | return; |
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| 123 | } |
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| 124 | |
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| 125 | |
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| 126 | G4double G4StatMFChannel::GetFragmentsCoulombEnergy(void) |
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| 127 | { |
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| 128 | G4double Coulomb = std::accumulate(_theFragments.begin(),_theFragments.end(), |
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| 129 | 0.0,SumCoulombEnergy()); |
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| 130 | // G4double Coulomb = 0.0; |
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| 131 | // for (unsigned int i = 0;i < _theFragments.size(); i++) |
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| 132 | // Coulomb += _theFragments[i]->GetCoulombEnergy(); |
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| 133 | return Coulomb; |
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| 134 | } |
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| 135 | |
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| 136 | |
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| 137 | |
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| 138 | G4double G4StatMFChannel::GetFragmentsEnergy(const G4double T) const |
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| 139 | { |
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| 140 | G4double Energy = 0.0; |
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| 141 | |
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| 142 | G4double TranslationalEnergy = (3./2.)*T*static_cast<G4double>(_theFragments.size()); |
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| 143 | |
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| 144 | std::deque<G4StatMFFragment*>::const_iterator i; |
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| 145 | for (i = _theFragments.begin(); i != _theFragments.end(); ++i) |
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| 146 | { |
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| 147 | Energy += (*i)->GetEnergy(T); |
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| 148 | } |
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| 149 | return Energy + TranslationalEnergy; |
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| 150 | } |
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| 151 | |
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| 152 | G4FragmentVector * G4StatMFChannel::GetFragments(const G4double anA, |
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| 153 | const G4double anZ, |
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| 154 | const G4double T) |
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| 155 | // |
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| 156 | { |
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| 157 | // calculate momenta of charged fragments |
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| 158 | CoulombImpulse(anA,anZ,T); |
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| 159 | |
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| 160 | // calculate momenta of neutral fragments |
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| 161 | FragmentsMomenta(_NumOfNeutralFragments, _NumOfChargedFragments, T); |
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| 162 | |
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| 163 | |
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| 164 | G4FragmentVector * theResult = new G4FragmentVector; |
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| 165 | std::deque<G4StatMFFragment*>::iterator i; |
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| 166 | for (i = _theFragments.begin(); i != _theFragments.end(); ++i) |
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| 167 | theResult->push_back((*i)->GetFragment(T)); |
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| 168 | |
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| 169 | return theResult; |
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| 170 | |
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| 171 | } |
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| 172 | |
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| 173 | |
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| 174 | |
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| 175 | void G4StatMFChannel::CoulombImpulse(const G4double anA, const G4double anZ, const G4double T) |
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| 176 | // Aafter breakup, fragments fly away under Coulomb field. |
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| 177 | // This method calculates asymptotic fragments momenta. |
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| 178 | { |
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| 179 | // First, we have to place the fragments inside of the original nucleus volume |
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| 180 | PlaceFragments(anA); |
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| 181 | |
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| 182 | // Second, we sample initial charged fragments momenta. There are |
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| 183 | // _NumOfChargedFragments charged fragments and they start at the begining |
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| 184 | // of the vector _theFragments (i.e. 0) |
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| 185 | FragmentsMomenta(_NumOfChargedFragments, 0, T); |
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| 186 | |
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| 187 | // Third, we have to figure out the asymptotic momenta of charged fragments |
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| 188 | // For taht we have to solve equations of motion for fragments |
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| 189 | SolveEqOfMotion(anA,anZ,T); |
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| 190 | |
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| 191 | return; |
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| 192 | } |
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| 193 | |
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| 194 | |
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| 195 | |
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| 196 | void G4StatMFChannel::PlaceFragments(const G4double anA) |
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| 197 | // This gives the position of fragments at the breakup instant. |
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| 198 | // Fragments positions are sampled inside prolongated ellipsoid. |
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| 199 | { |
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| 200 | const G4double R0 = G4StatMFParameters::Getr0(); |
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| 201 | const G4double Rsys = 2.0*R0*std::pow(anA,1./3.); |
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| 202 | |
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| 203 | G4bool TooMuchIterations; |
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| 204 | do |
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| 205 | { |
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| 206 | TooMuchIterations = false; |
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| 207 | |
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| 208 | // Sample the position of the first fragment |
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| 209 | G4double R = (Rsys - R0*std::pow(_theFragments[0]->GetA(),1./3.))* |
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| 210 | std::pow(G4UniformRand(),1./3.); |
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| 211 | _theFragments[0]->SetPosition(IsotropicVector(R)); |
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| 212 | |
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| 213 | |
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| 214 | // Sample the position of the remaining fragments |
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| 215 | G4bool ThereAreOverlaps = false; |
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| 216 | std::deque<G4StatMFFragment*>::iterator i; |
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| 217 | for (i = _theFragments.begin()+1; i != _theFragments.end(); ++i) |
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| 218 | { |
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| 219 | G4int counter = 0; |
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| 220 | do |
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| 221 | { |
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| 222 | R = (Rsys - R0*std::pow((*i)->GetA(),1./3.))*std::pow(G4UniformRand(),1./3.); |
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| 223 | (*i)->SetPosition(IsotropicVector(R)); |
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| 224 | |
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| 225 | // Check that there are not overlapping fragments |
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| 226 | std::deque<G4StatMFFragment*>::iterator j; |
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| 227 | for (j = _theFragments.begin(); j != i; ++j) |
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| 228 | { |
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| 229 | G4ThreeVector FragToFragVector = (*i)->GetPosition() - (*j)->GetPosition(); |
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| 230 | G4double Rmin = R0*(std::pow((*i)->GetA(),1./3.) + |
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| 231 | std::pow((*j)->GetA(),1./3)); |
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| 232 | if ( (ThereAreOverlaps = (FragToFragVector.mag2() < Rmin*Rmin)) ) break; |
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| 233 | } |
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| 234 | counter++; |
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| 235 | } while (ThereAreOverlaps && counter < 1000); |
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| 236 | |
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| 237 | if (counter >= 1000) |
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| 238 | { |
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| 239 | TooMuchIterations = true; |
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| 240 | break; |
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| 241 | } |
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| 242 | } |
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| 243 | } while (TooMuchIterations); |
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| 244 | |
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| 245 | return; |
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| 246 | } |
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| 247 | |
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| 248 | |
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| 249 | void G4StatMFChannel::FragmentsMomenta(const G4int NF, const G4int idx, |
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| 250 | const G4double T) |
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| 251 | // Calculate fragments momenta at the breakup instant |
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| 252 | // Fragment kinetic energies are calculated according to the |
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| 253 | // Boltzmann distribution at given temperature. |
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| 254 | // NF is number of fragments |
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| 255 | // idx is index of first fragment |
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| 256 | { |
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| 257 | G4double KinE = (3./2.)*T*static_cast<G4double>(NF); |
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| 258 | |
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| 259 | G4ThreeVector p; |
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| 260 | |
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| 261 | if (NF <= 0) return; |
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| 262 | else if (NF == 1) |
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| 263 | { |
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| 264 | // We have only one fragment to deal with |
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| 265 | p = IsotropicVector(std::sqrt(2.0*_theFragments[idx]->GetNuclearMass()*KinE)); |
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| 266 | _theFragments[idx]->SetMomentum(p); |
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| 267 | } |
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| 268 | else if (NF == 2) |
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| 269 | { |
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| 270 | // We have only two fragment to deal with |
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| 271 | G4double M1 = _theFragments[idx]->GetNuclearMass(); |
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| 272 | G4double M2 = _theFragments[idx+1]->GetNuclearMass(); |
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| 273 | p = IsotropicVector(std::sqrt(2.0*KinE*(M1*M2)/(M1+M2))); |
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| 274 | _theFragments[idx]->SetMomentum(p); |
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| 275 | _theFragments[idx+1]->SetMomentum(-p); |
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| 276 | } |
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| 277 | else |
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| 278 | { |
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| 279 | // We have more than two fragments |
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| 280 | G4double AvailableE; |
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| 281 | G4int i1,i2; |
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| 282 | G4double SummedE; |
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| 283 | G4ThreeVector SummedP; |
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| 284 | do |
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| 285 | { |
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| 286 | // Fisrt sample momenta of NF-2 fragments |
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| 287 | // according to Boltzmann distribution |
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| 288 | AvailableE = 0.0; |
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| 289 | SummedE = 0.0; |
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| 290 | SummedP.setX(0.0);SummedP.setY(0.0);SummedP.setZ(0.0); |
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| 291 | for (G4int i = idx; i < idx+NF-2; i++) |
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| 292 | { |
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| 293 | G4double E; |
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| 294 | G4double RandE; |
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| 295 | G4double Boltzmann; |
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| 296 | do |
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| 297 | { |
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| 298 | E = 9.0*T*G4UniformRand(); |
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| 299 | Boltzmann = std::sqrt(E)*std::exp(-E/T); |
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| 300 | RandE = std::sqrt(T/2.)*std::exp(-0.5)*G4UniformRand(); |
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| 301 | } |
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| 302 | while (RandE > Boltzmann); |
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| 303 | p = IsotropicVector(std::sqrt(2.0*E*_theFragments[i]->GetNuclearMass())); |
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| 304 | _theFragments[i]->SetMomentum(p); |
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| 305 | SummedE += E; |
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| 306 | SummedP += p; |
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| 307 | } |
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| 308 | // Calculate momenta of last two fragments in such a way |
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| 309 | // that constraints are satisfied |
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| 310 | i1 = idx+NF-2; // before last fragment index |
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| 311 | i2 = idx+NF-1; // last fragment index |
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| 312 | p = -SummedP; |
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| 313 | AvailableE = KinE - SummedE; |
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| 314 | // Available Kinetic Energy should be shared between two last fragments |
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| 315 | } |
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| 316 | while (AvailableE <= p.mag2()/(2.0*(_theFragments[i1]->GetNuclearMass()+ |
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| 317 | _theFragments[i2]->GetNuclearMass()))); |
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| 318 | |
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| 319 | G4double H = 1.0 + _theFragments[i2]->GetNuclearMass()/_theFragments[i1]->GetNuclearMass(); |
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| 320 | G4double CTM12 = H*(1.0 - 2.0*_theFragments[i2]->GetNuclearMass()*AvailableE/p.mag2()); |
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| 321 | G4double CosTheta1; |
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| 322 | G4double Sign; |
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| 323 | |
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[962] | 324 | if (CTM12 > 0.9999) {CosTheta1 = 1.;} |
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| 325 | else { |
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| 326 | do |
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| 327 | { |
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| 328 | do |
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| 329 | { |
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| 330 | CosTheta1 = 1.0 - 2.0*G4UniformRand(); |
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| 331 | } |
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| 332 | while (CosTheta1*CosTheta1 < CTM12); |
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| 333 | } |
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| 334 | while (CTM12 >= 0.0 && CosTheta1 < 0.0); |
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| 335 | } |
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| 336 | |
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[819] | 337 | if (CTM12 < 0.0) Sign = 1.0; |
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| 338 | else if (G4UniformRand() <= 0.5) Sign = -1.0; |
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| 339 | else Sign = 1.0; |
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| 340 | |
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| 341 | |
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| 342 | G4double P1 = (p.mag()*CosTheta1+Sign*std::sqrt(p.mag2()*(CosTheta1*CosTheta1-CTM12)))/H; |
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| 343 | G4double P2 = std::sqrt(P1*P1+p.mag2() - 2.0*P1*p.mag()*CosTheta1); |
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| 344 | G4double Phi = twopi*G4UniformRand(); |
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| 345 | G4double SinTheta1 = std::sqrt(1.0 - CosTheta1*CosTheta1); |
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| 346 | G4double CosPhi1 = std::cos(Phi); |
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| 347 | G4double SinPhi1 = std::sin(Phi); |
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| 348 | G4double CosPhi2 = -CosPhi1; |
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| 349 | G4double SinPhi2 = -SinPhi1; |
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| 350 | G4double CosTheta2 = (p.mag2() + P2*P2 - P1*P1)/(2.0*p.mag()*P2); |
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| 351 | G4double SinTheta2 = 0.0; |
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| 352 | if (CosTheta2 > -1.0 && CosTheta2 < 1.0) SinTheta2 = std::sqrt(1.0 - CosTheta2*CosTheta2); |
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| 353 | |
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| 354 | G4ThreeVector p1(P1*SinTheta1*CosPhi1,P1*SinTheta1*SinPhi1,P1*CosTheta1); |
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| 355 | G4ThreeVector p2(P2*SinTheta2*CosPhi2,P2*SinTheta2*SinPhi2,P2*CosTheta2); |
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| 356 | G4ThreeVector b(1.0,0.0,0.0); |
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| 357 | |
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| 358 | p1 = RotateMomentum(p,b,p1); |
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| 359 | p2 = RotateMomentum(p,b,p2); |
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| 360 | |
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| 361 | SummedP += p1 + p2; |
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| 362 | SummedE += p1.mag2()/(2.0*_theFragments[i1]->GetNuclearMass()) + |
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| 363 | p2.mag2()/(2.0*_theFragments[i2]->GetNuclearMass()); |
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| 364 | |
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| 365 | _theFragments[i1]->SetMomentum(p1); |
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| 366 | _theFragments[i2]->SetMomentum(p2); |
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| 367 | |
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| 368 | } |
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| 369 | |
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| 370 | return; |
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| 371 | } |
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| 372 | |
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| 373 | |
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| 374 | void G4StatMFChannel::SolveEqOfMotion(const G4double anA, const G4double anZ, const G4double T) |
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| 375 | // This method will find a solution of Newton's equation of motion |
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| 376 | // for fragments in the self-consistent time-dependent Coulomb field |
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| 377 | { |
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| 378 | G4double CoulombEnergy = (3./5.)*(elm_coupling*anZ*anZ)* |
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| 379 | std::pow(1.0+G4StatMFParameters::GetKappaCoulomb(),1./3.)/ |
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| 380 | (G4StatMFParameters::Getr0()*std::pow(anA,1./3.)) |
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| 381 | - GetFragmentsCoulombEnergy(); |
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| 382 | if (CoulombEnergy <= 0.0) return; |
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| 383 | |
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| 384 | G4int Iterations = 0; |
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| 385 | G4double TimeN = 0.0; |
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| 386 | G4double TimeS = 0.0; |
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| 387 | G4double DeltaTime = 10.0; |
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| 388 | |
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| 389 | G4ThreeVector * Pos = new G4ThreeVector[_NumOfChargedFragments]; |
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| 390 | G4ThreeVector * Vel = new G4ThreeVector[_NumOfChargedFragments]; |
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| 391 | G4ThreeVector * Accel = new G4ThreeVector[_NumOfChargedFragments]; |
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| 392 | |
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| 393 | G4int i; |
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| 394 | for (i = 0; i < _NumOfChargedFragments; i++) |
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| 395 | { |
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| 396 | Vel[i] = (1.0/(_theFragments[i]->GetNuclearMass()))* |
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| 397 | _theFragments[i]->GetMomentum(); |
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| 398 | Pos[i] = _theFragments[i]->GetPosition(); |
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| 399 | } |
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| 400 | |
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| 401 | do |
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| 402 | { |
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| 403 | |
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| 404 | G4ThreeVector distance; |
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| 405 | G4ThreeVector force; |
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| 406 | |
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| 407 | for (i = 0; i < _NumOfChargedFragments; i++) |
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| 408 | { |
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| 409 | force.setX(0.0); force.setY(0.0); force.setZ(0.0); |
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| 410 | for (G4int j = 0; j < _NumOfChargedFragments; j++) |
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| 411 | { |
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| 412 | if (i != j) |
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| 413 | { |
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| 414 | distance = Pos[i] - Pos[j]; |
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| 415 | force += (elm_coupling*(_theFragments[i]->GetZ()*_theFragments[j]->GetZ())/ |
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| 416 | (distance.mag2()*distance.mag()))*distance; |
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| 417 | } |
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| 418 | } |
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| 419 | Accel[i] = (1./(_theFragments[i]->GetNuclearMass()))*force; |
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| 420 | } |
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| 421 | |
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| 422 | TimeN = TimeS + DeltaTime; |
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| 423 | |
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| 424 | G4ThreeVector SavedVel; |
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| 425 | for ( i = 0; i < _NumOfChargedFragments; i++) |
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| 426 | { |
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| 427 | SavedVel = Vel[i]; |
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| 428 | Vel[i] += Accel[i]*(TimeN-TimeS); |
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| 429 | Pos[i] += (SavedVel+Vel[i])*(TimeN-TimeS)*0.5; |
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| 430 | } |
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| 431 | |
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| 432 | // if (Iterations >= 50 && Iterations < 75) DeltaTime = 4.; |
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| 433 | // else if (Iterations >= 75) DeltaTime = 10.; |
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| 434 | |
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| 435 | TimeS = TimeN; |
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| 436 | |
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| 437 | } |
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| 438 | while (Iterations++ < 100); |
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| 439 | |
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| 440 | // Summed fragment kinetic energy |
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| 441 | G4double TotalKineticEnergy = 0.0; |
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| 442 | for (i = 0; i < _NumOfChargedFragments; i++) |
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| 443 | { |
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| 444 | TotalKineticEnergy += _theFragments[i]->GetNuclearMass()* |
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| 445 | 0.5*Vel[i].mag2(); |
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| 446 | } |
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| 447 | // Scaling of fragment velocities |
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| 448 | G4double KineticEnergy = (3./2.)*static_cast<G4double>(_theFragments.size())*T; |
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| 449 | G4double Eta = ( CoulombEnergy + KineticEnergy ) / TotalKineticEnergy; |
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| 450 | for (i = 0; i < _NumOfChargedFragments; i++) |
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| 451 | { |
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| 452 | Vel[i] *= Eta; |
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| 453 | } |
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| 454 | |
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| 455 | // Finally calculate fragments momenta |
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| 456 | for (i = 0; i < _NumOfChargedFragments; i++) |
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| 457 | { |
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| 458 | _theFragments[i]->SetMomentum(_theFragments[i]->GetNuclearMass()*Vel[i]); |
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| 459 | } |
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| 460 | |
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| 461 | // garbage collection |
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| 462 | delete [] Pos; |
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| 463 | delete [] Vel; |
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| 464 | delete [] Accel; |
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| 465 | |
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| 466 | return; |
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| 467 | } |
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| 468 | |
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| 469 | |
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| 470 | |
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| 471 | G4ThreeVector G4StatMFChannel::RotateMomentum(G4ThreeVector Pa, |
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| 472 | G4ThreeVector V, G4ThreeVector P) |
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| 473 | // Rotates a 3-vector P to close momentum triangle Pa + V + P = 0 |
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| 474 | { |
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| 475 | G4ThreeVector U = Pa.unit(); |
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| 476 | |
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| 477 | G4double Alpha1 = U * V; |
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| 478 | |
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| 479 | G4double Alpha2 = std::sqrt(V.mag2() - Alpha1*Alpha1); |
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| 480 | |
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| 481 | G4ThreeVector N = (1./Alpha2)*U.cross(V); |
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| 482 | |
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| 483 | G4ThreeVector RotatedMomentum( |
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| 484 | ( (V.x() - Alpha1*U.x())/Alpha2 ) * P.x() + N.x() * P.y() + U.x() * P.z(), |
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| 485 | ( (V.y() - Alpha1*U.y())/Alpha2 ) * P.x() + N.y() * P.y() + U.y() * P.z(), |
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| 486 | ( (V.z() - Alpha1*U.z())/Alpha2 ) * P.x() + N.z() * P.y() + U.z() * P.z() |
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| 487 | ); |
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| 488 | return RotatedMomentum; |
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| 489 | } |
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| 490 | |
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| 491 | |
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| 492 | |
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| 493 | |
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| 494 | |
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| 495 | G4ThreeVector G4StatMFChannel::IsotropicVector(const G4double Magnitude) |
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| 496 | // Samples a isotropic random vector with a magnitud given by Magnitude. |
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| 497 | // By default Magnitude = 1 |
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| 498 | { |
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| 499 | G4double CosTheta = 1.0 - 2.0*G4UniformRand(); |
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| 500 | G4double SinTheta = std::sqrt(1.0 - CosTheta*CosTheta); |
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| 501 | G4double Phi = twopi*G4UniformRand(); |
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| 502 | G4ThreeVector Vector(Magnitude*std::cos(Phi)*SinTheta, |
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| 503 | Magnitude*std::cos(Phi)*CosTheta, |
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| 504 | Magnitude*std::sin(Phi)); |
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| 505 | return Vector; |
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| 506 | } |
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