| Geant4 Cross Reference |
1 // 1 //
2 // ******************************************* 2 // ********************************************************************
3 // * License and Disclaimer 3 // * License and Disclaimer *
4 // * 4 // * *
5 // * The Geant4 software is copyright of th 5 // * The Geant4 software is copyright of the Copyright Holders of *
6 // * the Geant4 Collaboration. It is provided 6 // * the Geant4 Collaboration. It is provided under the terms and *
7 // * conditions of the Geant4 Software License 7 // * conditions of the Geant4 Software License, included in the file *
8 // * LICENSE and available at http://cern.ch/ 8 // * LICENSE and available at http://cern.ch/geant4/license . These *
9 // * include a list of copyright holders. 9 // * include a list of copyright holders. *
10 // * 10 // * *
11 // * Neither the authors of this software syst 11 // * Neither the authors of this software system, nor their employing *
12 // * institutes,nor the agencies providing fin 12 // * institutes,nor the agencies providing financial support for this *
13 // * work make any representation or warran 13 // * work make any representation or warranty, express or implied, *
14 // * regarding this software system or assum 14 // * regarding this software system or assume any liability for its *
15 // * use. Please see the license in the file 15 // * use. Please see the license in the file LICENSE and URL above *
16 // * for the full disclaimer and the limitatio 16 // * for the full disclaimer and the limitation of liability. *
17 // * 17 // * *
18 // * This code implementation is the result 18 // * This code implementation is the result of the scientific and *
19 // * technical work of the GEANT4 collaboratio 19 // * technical work of the GEANT4 collaboration. *
20 // * By using, copying, modifying or distri 20 // * By using, copying, modifying or distributing the software (or *
21 // * any work based on the software) you ag 21 // * any work based on the software) you agree to acknowledge its *
22 // * use in resulting scientific publicati 22 // * use in resulting scientific publications, and indicate your *
23 // * acceptance of all terms of the Geant4 Sof 23 // * acceptance of all terms of the Geant4 Software license. *
24 // ******************************************* 24 // ********************************************************************
25 // 25 //
26 // 26 //
>> 27 // $Id: G4ElasticHNScattering.cc 74627 2013-10-17 07:04:38Z gcosmo $
27 // 28 //
28 29
29 // ------------------------------------------- 30 // ------------------------------------------------------------
30 // GEANT 4 class implemetation file 31 // GEANT 4 class implemetation file
31 // 32 //
32 // ---------------- G4ElasticHNScattering 33 // ---------------- G4ElasticHNScattering --------------
33 // by V. Uzhinsky, March 200 34 // by V. Uzhinsky, March 2008.
34 // elastic scattering used by Frit 35 // elastic scattering used by Fritiof model
35 // Take a projectile and a tar 36 // Take a projectile and a target
36 // scatter the projectile and 37 // scatter the projectile and target
37 // ------------------------------------------- 38 // ---------------------------------------------------------------------
38 39
39 #include "globals.hh" 40 #include "globals.hh"
40 #include "Randomize.hh" 41 #include "Randomize.hh"
41 #include "G4PhysicalConstants.hh" 42 #include "G4PhysicalConstants.hh"
42 #include "G4SystemOfUnits.hh" <<
43 43
44 #include "G4ElasticHNScattering.hh" 44 #include "G4ElasticHNScattering.hh"
45 #include "G4LorentzRotation.hh" 45 #include "G4LorentzRotation.hh"
46 #include "G4ThreeVector.hh" 46 #include "G4ThreeVector.hh"
47 #include "G4ParticleDefinition.hh" 47 #include "G4ParticleDefinition.hh"
48 #include "G4VSplitableHadron.hh" 48 #include "G4VSplitableHadron.hh"
49 #include "G4ExcitedString.hh" 49 #include "G4ExcitedString.hh"
50 #include "G4FTFParameters.hh" 50 #include "G4FTFParameters.hh"
>> 51 //#include "G4ios.hh"
51 52
52 #include "G4SampleResonance.hh" <<
53 <<
54 #include "G4Exp.hh" <<
55 #include "G4Log.hh" <<
56 53
57 //============================================ 54 //============================================================================
58 55
59 G4ElasticHNScattering::G4ElasticHNScattering() 56 G4ElasticHNScattering::G4ElasticHNScattering() {}
60 57
61 58
62 //============================================ 59 //============================================================================
63 60
64 G4bool G4ElasticHNScattering::ElasticScatterin 61 G4bool G4ElasticHNScattering::ElasticScattering( G4VSplitableHadron* projectile,
65 62 G4VSplitableHadron* target,
66 63 G4FTFParameters* theParameters ) const {
67 projectile->IncrementCollisionCount( 1 ); 64 projectile->IncrementCollisionCount( 1 );
68 target->IncrementCollisionCount( 1 ); 65 target->IncrementCollisionCount( 1 );
69 66
70 if ( projectile->Get4Momentum().z() < 0.0 ) <<
71 <<
72 // Projectile parameters 67 // Projectile parameters
73 G4LorentzVector Pprojectile = projectile->Ge 68 G4LorentzVector Pprojectile = projectile->Get4Momentum();
74 G4double M0projectile = Pprojectile.mag(); << 69 if ( Pprojectile.z() < 0.0 ) return false;
>> 70 G4bool PutOnMassShell( false );
>> 71 G4double M0projectile = Pprojectile.mag();
>> 72 if ( M0projectile < projectile->GetDefinition()->GetPDGMass() ) {
>> 73 PutOnMassShell = true;
>> 74 M0projectile = projectile->GetDefinition()->GetPDGMass();
>> 75 }
75 G4double M0projectile2 = M0projectile * M0pr 76 G4double M0projectile2 = M0projectile * M0projectile;
>> 77 G4double AveragePt2 = theParameters->GetAvaragePt2ofElasticScattering();
76 78
77 // Target parameters 79 // Target parameters
78 G4LorentzVector Ptarget = target->Get4Moment 80 G4LorentzVector Ptarget = target->Get4Momentum();
79 G4double M0target = Ptarget.mag(); 81 G4double M0target = Ptarget.mag();
80 G4double M0target2 = M0target * M0target; << 82 if ( M0target < target->GetDefinition()->GetPDGMass() ) {
81 << 83 PutOnMassShell = true;
82 G4double AveragePt2 = theParameters->GetAvar << 84 M0target = target->GetDefinition()->GetPDGMass();
>> 85 }
>> 86 G4double M0target2 = M0target * M0target;
83 87
84 // Transform momenta to cms and then rotate 88 // Transform momenta to cms and then rotate parallel to z axis;
85 G4LorentzVector Psum; 89 G4LorentzVector Psum;
86 Psum = Pprojectile + Ptarget; 90 Psum = Pprojectile + Ptarget;
87 G4LorentzRotation toCms( -1*Psum.boostVector 91 G4LorentzRotation toCms( -1*Psum.boostVector() );
88 G4LorentzVector Ptmp = toCms*Pprojectile; 92 G4LorentzVector Ptmp = toCms*Pprojectile;
89 if ( Ptmp.pz() <= 0.0 ) return false; 93 if ( Ptmp.pz() <= 0.0 ) return false;
90 //"String" moving backwards in CMS, abort c << 94 // "String" moving backwards in CMS, abort collision !
91 //G4cout << " abort Collision! " << G4endl; 95 //G4cout << " abort Collision! " << G4endl;
92 toCms.rotateZ( -1*Ptmp.phi() ); 96 toCms.rotateZ( -1*Ptmp.phi() );
93 toCms.rotateY( -1*Ptmp.theta() ); 97 toCms.rotateY( -1*Ptmp.theta() );
94 G4LorentzRotation toLab( toCms.inverse() ); 98 G4LorentzRotation toLab( toCms.inverse() );
95 Pprojectile.transform( toCms ); 99 Pprojectile.transform( toCms );
96 Ptarget.transform( toCms ); 100 Ptarget.transform( toCms );
97 101
>> 102 // Putting on mass-on-shell, if needed
98 G4double PZcms2, PZcms; 103 G4double PZcms2, PZcms;
99 G4double S = Psum.mag2(); 104 G4double S = Psum.mag2();
100 G4double SqrtS = std::sqrt( S ); 105 G4double SqrtS = std::sqrt( S );
101 if ( SqrtS < M0projectile + M0target ) retur 106 if ( SqrtS < M0projectile + M0target ) return false;
102 107
103 PZcms2 = ( S*S + sqr( M0projectile2 ) + sqr( 108 PZcms2 = ( S*S + sqr( M0projectile2 ) + sqr( M0target2 )
104 - 2*S*M0projectile2 - 2*S*M0targe 109 - 2*S*M0projectile2 - 2*S*M0target2 - 2*M0projectile2*M0target2 ) / 4.0 / S;
105 110
106 PZcms = ( PZcms2 > 0.0 ? std::sqrt( PZcms2 ) << 111 if ( PZcms2 < 0.0 ) { // It can be in an interaction with off-shell nuclear nucleon
>> 112 if ( M0projectile > projectile->GetDefinition()->GetPDGMass() ) {
>> 113 // An attempt to de-excite the projectile
>> 114 // It is assumed that the target is in the ground state
>> 115 M0projectile = projectile->GetDefinition()->GetPDGMass();
>> 116 M0projectile2 = M0projectile * M0projectile;
>> 117 PZcms2= ( S*S + sqr( M0projectile2 ) + sqr( M0target2 )
>> 118 - 2*S*M0projectile2 - 2*S*M0target2 - 2*M0projectile2*M0target2 ) / 4.0 / S;
>> 119 if ( PZcms2 < 0.0 ) { return false; } // Nonsuccesful attempt to de-excitate the projectile
>> 120 } else {
>> 121 return false; // The projectile was not excited, but the energy was too low to put
>> 122 // the target nucleon on mass-shell
>> 123 }
>> 124 }
>> 125
>> 126 PZcms = std::sqrt( PZcms2 );
>> 127
>> 128 if ( PutOnMassShell ) {
>> 129 if ( Pprojectile.z() > 0.0 ) {
>> 130 Pprojectile.setPz( PZcms );
>> 131 Ptarget.setPz( -PZcms );
>> 132 } else {
>> 133 Pprojectile.setPz( -PZcms );
>> 134 Ptarget.setPz( PZcms );
>> 135 };
>> 136 Pprojectile.setE( std::sqrt( M0projectile2 + Pprojectile.x() * Pprojectile.x() +
>> 137 Pprojectile.y() * Pprojectile.y() + PZcms2 ) );
>> 138 Ptarget.setE( std::sqrt( M0target2 + Ptarget.x() * Ptarget.x() + Ptarget.y() * Ptarget.y() +
>> 139 PZcms2 ) );
>> 140 }
107 141
108 G4double maxPtSquare = PZcms2; 142 G4double maxPtSquare = PZcms2;
109 143
110 // Now we can calculate the transferred Pt 144 // Now we can calculate the transferred Pt
111 G4double Pt2; 145 G4double Pt2;
112 G4double ProjMassT2, ProjMassT; 146 G4double ProjMassT2, ProjMassT;
113 G4double TargMassT2, TargMassT; 147 G4double TargMassT2, TargMassT;
114 G4LorentzVector Qmomentum; 148 G4LorentzVector Qmomentum;
115 149
116 const G4int maxNumberOfLoops = 1000; <<
117 G4int loopCounter = 0; <<
118 do { 150 do {
119 Qmomentum = G4LorentzVector( GaussianPt( A 151 Qmomentum = G4LorentzVector( GaussianPt( AveragePt2, maxPtSquare ), 0.0 );
120 Pt2 = G4ThreeVector( Qmomentum.vect() ).ma 152 Pt2 = G4ThreeVector( Qmomentum.vect() ).mag2();
121 ProjMassT2 = M0projectile2 + Pt2; 153 ProjMassT2 = M0projectile2 + Pt2;
122 ProjMassT = std::sqrt( ProjMassT2 ); 154 ProjMassT = std::sqrt( ProjMassT2 );
123 TargMassT2 = M0target2 + Pt2; 155 TargMassT2 = M0target2 + Pt2;
124 TargMassT = std::sqrt( TargMassT2 ); 156 TargMassT = std::sqrt( TargMassT2 );
125 } while ( ( SqrtS < ProjMassT + TargMassT ) << 157 } while ( SqrtS < ProjMassT + TargMassT );
126 ++loopCounter < maxNumberOfLoops ) <<
127 if ( loopCounter >= maxNumberOfLoops ) { <<
128 return false; <<
129 } <<
130 158
131 PZcms2 = ( S*S + sqr( ProjMassT2 ) + sqr( Ta 159 PZcms2 = ( S*S + sqr( ProjMassT2 ) + sqr( TargMassT2 )
132 - 2.0*S*ProjMassT2 - 2.0*S*TargMa 160 - 2.0*S*ProjMassT2 - 2.0*S*TargMassT2 - 2.0*ProjMassT2*TargMassT2 ) / 4.0 / S;
133 161
134 if ( PZcms2 < 0.0 ) { PZcms2 = 0.0; }; // t 162 if ( PZcms2 < 0.0 ) { PZcms2 = 0.0; }; // to avoid the exactness problem
135 PZcms = std::sqrt( PZcms2 ); 163 PZcms = std::sqrt( PZcms2 );
136 Pprojectile.setPz( PZcms ); 164 Pprojectile.setPz( PZcms );
137 Ptarget.setPz( -PZcms ); 165 Ptarget.setPz( -PZcms );
138 Pprojectile += Qmomentum; 166 Pprojectile += Qmomentum;
139 Ptarget -= Qmomentum; 167 Ptarget -= Qmomentum;
140 168
141 // Transform back and update SplitableHadron 169 // Transform back and update SplitableHadron Participant.
142 Pprojectile.transform( toLab ); 170 Pprojectile.transform( toLab );
143 Ptarget.transform( toLab ); 171 Ptarget.transform( toLab );
144 172
145 // Calculation of the creation time 173 // Calculation of the creation time
146 projectile->SetTimeOfCreation( target->GetTi 174 projectile->SetTimeOfCreation( target->GetTimeOfCreation() );
147 projectile->SetPosition( target->GetPosition 175 projectile->SetPosition( target->GetPosition() );
148 176
149 // Creation time and position of target nucl 177 // Creation time and position of target nucleon were determined at
150 // ReggeonCascade() of G4FTFModel 178 // ReggeonCascade() of G4FTFModel
151 179
152 projectile->Set4Momentum( Pprojectile ); 180 projectile->Set4Momentum( Pprojectile );
153 target->Set4Momentum( Ptarget ); 181 target->Set4Momentum( Ptarget );
154 182
155 //projectile->IncrementCollisionCount( 1 ); 183 //projectile->IncrementCollisionCount( 1 );
156 //target->IncrementCollisionCount( 1 ); 184 //target->IncrementCollisionCount( 1 );
157 185
158 return true; 186 return true;
159 } 187 }
160 188
161 189
162 //============================================ 190 //============================================================================
163 191
164 G4ThreeVector G4ElasticHNScattering::GaussianP 192 G4ThreeVector G4ElasticHNScattering::GaussianPt( G4double AveragePt2,
165 193 G4double maxPtSquare ) const {
166 // @@ this method is used in FTFModel as wel 194 // @@ this method is used in FTFModel as well. Should go somewhere common!
167 G4double Pt2( 0.0 ); 195 G4double Pt2( 0.0 );
168 if ( AveragePt2 <= 0.0 ) { 196 if ( AveragePt2 <= 0.0 ) {
169 Pt2 = 0.0; 197 Pt2 = 0.0;
170 } else { 198 } else {
171 Pt2 = -AveragePt2 * G4Log( 1.0 + G4Uniform << 199 Pt2 = -AveragePt2 * std::log( 1.0 + G4UniformRand() *
>> 200 ( std::exp( -maxPtSquare/AveragePt2 ) -1.0 ) );
172 } 201 }
173 G4double Pt = ( Pt2 > 0.0 ? std::sqrt( Pt2 ) << 202 G4double Pt = std::sqrt( Pt2 );
174 G4double phi = G4UniformRand() * twopi; 203 G4double phi = G4UniformRand() * twopi;
175 return G4ThreeVector( Pt * std::cos( phi ), 204 return G4ThreeVector( Pt * std::cos( phi ), Pt * std::sin( phi ), 0.0 );
176 } 205 }
177 206
178 207
179 //============================================ 208 //============================================================================
180 209
181 G4ElasticHNScattering::G4ElasticHNScattering( 210 G4ElasticHNScattering::G4ElasticHNScattering( const G4ElasticHNScattering& ) {
182 throw G4HadronicException( __FILE__, __LINE_ 211 throw G4HadronicException( __FILE__, __LINE__,
183 "G4ElasticHNScatt << 212 "G4ElasticHNScattering copy contructor not meant to be called" );
184 } 213 }
185 214
186 215
187 //============================================ 216 //============================================================================
188 217
189 G4ElasticHNScattering::~G4ElasticHNScattering( 218 G4ElasticHNScattering::~G4ElasticHNScattering() {}
190 219
191 220
192 //============================================ 221 //============================================================================
193 222
194 const G4ElasticHNScattering & G4ElasticHNScatt 223 const G4ElasticHNScattering & G4ElasticHNScattering::operator=( const G4ElasticHNScattering& ) {
195 throw G4HadronicException( __FILE__, __LINE_ 224 throw G4HadronicException( __FILE__, __LINE__,
196 "G4ElasticHNScatt 225 "G4ElasticHNScattering = operator not meant to be called" );
197 } 226 }
198 227
199 228
200 //============================================ 229 //============================================================================
201 230
202 G4bool G4ElasticHNScattering::operator==( cons << 231 int G4ElasticHNScattering::operator==( const G4ElasticHNScattering& ) const {
203 throw G4HadronicException( __FILE__, __LINE__ 232 throw G4HadronicException( __FILE__, __LINE__,
204 "G4ElasticHNScatte 233 "G4ElasticHNScattering == operator not meant to be called" );
205 } 234 }
206 235
207 236
208 //============================================ 237 //============================================================================
209 238
210 G4bool G4ElasticHNScattering::operator!=( cons << 239 int G4ElasticHNScattering::operator!=( const G4ElasticHNScattering& ) const {
211 throw G4HadronicException( __FILE__, __LINE_ 240 throw G4HadronicException( __FILE__, __LINE__,
212 "G4ElasticHNScatte 241 "G4ElasticHNScattering != operator not meant to be called" );
213 } 242 }
214 <<
215 243