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25 // 25 //
26 #include "globals.hh" 26 #include "globals.hh"
27 #include "G4ios.hh" 27 #include "G4ios.hh"
28 #include "G4PhysicalConstants.hh" 28 #include "G4PhysicalConstants.hh"
29 #include "G4XAnnihilationChannel.hh" 29 #include "G4XAnnihilationChannel.hh"
30 #include "G4KineticTrack.hh" 30 #include "G4KineticTrack.hh"
31 #include "G4ParticleDefinition.hh" 31 #include "G4ParticleDefinition.hh"
32 #include "G4ResonanceWidth.hh" 32 #include "G4ResonanceWidth.hh"
33 #include "G4ResonancePartialWidth.hh" 33 #include "G4ResonancePartialWidth.hh"
34 #include "G4PhysicsVector.hh" 34 #include "G4PhysicsVector.hh"
35 #include "G4PartialWidthTable.hh" 35 #include "G4PartialWidthTable.hh"
36 36
37 G4XAnnihilationChannel::G4XAnnihilationChannel 37 G4XAnnihilationChannel::G4XAnnihilationChannel(): resonance(0)
38 { 38 {
39 // As a first approximation the model is ass 39 // As a first approximation the model is assumed to be valid over
40 // the entire energy range 40 // the entire energy range
41 lowLimit = 0.; 41 lowLimit = 0.;
42 highLimit = DBL_MAX; 42 highLimit = DBL_MAX;
43 widthTable = 0; 43 widthTable = 0;
44 partWidthTable = 0; 44 partWidthTable = 0;
45 } 45 }
46 46
47 G4XAnnihilationChannel::G4XAnnihilationChannel 47 G4XAnnihilationChannel::G4XAnnihilationChannel(const G4ParticleDefinition* resDefinition,
48 const G4ResonanceWidth& resWi 48 const G4ResonanceWidth& resWidths,
49 const G4ResonancePartialWidth 49 const G4ResonancePartialWidth& resPartWidths,
50 const G4String& partWidthLabe 50 const G4String& partWidthLabel)
51 : resonance(resDefinition) 51 : resonance(resDefinition)
52 { 52 {
53 // Get the tabulated mass-dependent widths f 53 // Get the tabulated mass-dependent widths for the resonance
54 G4String resName = resonance->GetParticleNam 54 G4String resName = resonance->GetParticleName();
55 // cout << "HPW "<<resName<<endl; 55 // cout << "HPW "<<resName<<endl;
56 G4String shortName = theNames.ShortName(resN 56 G4String shortName = theNames.ShortName(resName);
57 // cout << "HPW "<<shortName<<endl; 57 // cout << "HPW "<<shortName<<endl;
58 // cout << "HPW "<<partWidthLabel<<endl; 58 // cout << "HPW "<<partWidthLabel<<endl;
59 59
60 widthTable = resWidths.MassDependentWidth(sh 60 widthTable = resWidths.MassDependentWidth(shortName);
61 partWidthTable = resPartWidths.MassDependent 61 partWidthTable = resPartWidths.MassDependentWidth(partWidthLabel);
62 62
63 // As a first approximation the model is ass 63 // As a first approximation the model is assumed to be valid over
64 // the entire energy range 64 // the entire energy range
65 lowLimit = 0.; 65 lowLimit = 0.;
66 highLimit = DBL_MAX; 66 highLimit = DBL_MAX;
67 } 67 }
68 68
69 69
70 G4XAnnihilationChannel::~G4XAnnihilationChanne 70 G4XAnnihilationChannel::~G4XAnnihilationChannel()
71 { 71 {
72 if (widthTable) delete widthTable; 72 if (widthTable) delete widthTable;
73 widthTable = 0; 73 widthTable = 0;
74 if (partWidthTable) delete partWidthTable; 74 if (partWidthTable) delete partWidthTable;
75 partWidthTable = 0; 75 partWidthTable = 0;
76 } 76 }
77 77
78 78
79 G4bool G4XAnnihilationChannel::operator==(cons 79 G4bool G4XAnnihilationChannel::operator==(const G4XAnnihilationChannel &right) const
80 { 80 {
81 return (this == (G4XAnnihilationChannel *) & 81 return (this == (G4XAnnihilationChannel *) &right);
82 } 82 }
83 83
84 84
85 G4bool G4XAnnihilationChannel::operator!=(cons 85 G4bool G4XAnnihilationChannel::operator!=(const G4XAnnihilationChannel &right) const
86 { 86 {
87 return (this != (G4XAnnihilationChannel *) & 87 return (this != (G4XAnnihilationChannel *) &right);
88 } 88 }
89 89
90 90
91 G4double G4XAnnihilationChannel::CrossSection( 91 G4double G4XAnnihilationChannel::CrossSection(const G4KineticTrack& trk1,
92 const G4KineticTrack& trk2) co 92 const G4KineticTrack& trk2) const
93 { 93 {
94 G4double sigma = 0.; 94 G4double sigma = 0.;
95 G4double eCM = (trk1.Get4Momentum() + trk2.G 95 G4double eCM = (trk1.Get4Momentum() + trk2.Get4Momentum()).mag();
96 96
97 const G4ParticleDefinition* def1 = trk1.GetD 97 const G4ParticleDefinition* def1 = trk1.GetDefinition();
98 const G4ParticleDefinition* def2 = trk2.GetD 98 const G4ParticleDefinition* def2 = trk2.GetDefinition();
99 99
100 G4int J1 = def1->GetPDGiSpin(); 100 G4int J1 = def1->GetPDGiSpin();
101 G4int J2 = def2->GetPDGiSpin(); 101 G4int J2 = def2->GetPDGiSpin();
102 G4double m_1 = def1->GetPDGMass(); 102 G4double m_1 = def1->GetPDGMass();
103 G4double m_2 = def2->GetPDGMass(); 103 G4double m_2 = def2->GetPDGMass();
104 104
105 G4int JRes = resonance->GetPDGiSpin(); 105 G4int JRes = resonance->GetPDGiSpin();
106 G4double mRes = resonance->GetPDGMass(); 106 G4double mRes = resonance->GetPDGMass();
107 107
108 G4double branch = Branch(trk1,trk2); 108 G4double branch = Branch(trk1,trk2);
109 G4double width = VariableWidth(trk1,trk2); 109 G4double width = VariableWidth(trk1,trk2);
110 G4double cleb = NormalizedClebsch(trk1,trk2) 110 G4double cleb = NormalizedClebsch(trk1,trk2);
111 111
112 G4double S = eCM * eCM; 112 G4double S = eCM * eCM;
113 if (S == 0.) throw G4HadronicException(__FIL 113 if (S == 0.) throw G4HadronicException(__FILE__, __LINE__, "G4XAnnihilationChannel::CrossSection - eCM = 0");
114 114
115 G4double pCM = std::sqrt((S-(m_1+m_2)*(m_1+m 115 G4double pCM = std::sqrt((S-(m_1+m_2)*(m_1+m_2))*(S-(m_1-m_2)*(m_1-m_2))/(4.*S));
116 116
117 sigma = ( (JRes + 1.) / ( (J1 + 1) * (J2 + 1 117 sigma = ( (JRes + 1.) / ( (J1 + 1) * (J2 + 1) )
118 * pi / (pCM * pCM) * branch * width * wi 118 * pi / (pCM * pCM) * branch * width * width /
119 ( (eCM - mRes) * (eCM - mRes) + width * 119 ( (eCM - mRes) * (eCM - mRes) + width * width / 4.0) * cleb * hbarc_squared);
120 120
121 // G4cout << "SS " << branch<<" "<<sigma<<" 121 // G4cout << "SS " << branch<<" "<<sigma<<" "
122 // << J1 <<" " 122 // << J1 <<" "
123 // <<J2<<" " 123 // <<J2<<" "
124 // <<m1<<" " 124 // <<m1<<" "
125 // <<m2<<" " 125 // <<m2<<" "
126 // <<JRes<<" " 126 // <<JRes<<" "
127 // <<mRes<<" " 127 // <<mRes<<" "
128 // <<wRes<<" " 128 // <<wRes<<" "
129 // <<width<<" " 129 // <<width<<" "
130 // <<cleb<<" " 130 // <<cleb<<" "
131 // <<G4endl; 131 // <<G4endl;
132 return sigma; 132 return sigma;
133 } 133 }
134 134
135 135
136 G4String G4XAnnihilationChannel::Name() const 136 G4String G4XAnnihilationChannel::Name() const
137 { 137 {
138 G4String name("XAnnihilationChannelCrossSect 138 G4String name("XAnnihilationChannelCrossSection");
139 return name; 139 return name;
140 } 140 }
141 141
142 142
143 143
144 G4bool G4XAnnihilationChannel::IsValid(G4doubl 144 G4bool G4XAnnihilationChannel::IsValid(G4double e) const
145 { 145 {
146 G4bool answer = InLimits(e,lowLimit,highLimi 146 G4bool answer = InLimits(e,lowLimit,highLimit);
147 147
148 return answer; 148 return answer;
149 } 149 }
150 150
151 151
152 G4double G4XAnnihilationChannel::Branch(const 152 G4double G4XAnnihilationChannel::Branch(const G4KineticTrack& trk1,
153 const 153 const G4KineticTrack& trk2) const
154 { 154 {
155 G4double w=VariableWidth(trk1,trk2); 155 G4double w=VariableWidth(trk1,trk2);
156 if(w==0) return 0; 156 if(w==0) return 0;
157 return VariablePartialWidth(trk1,trk2) / Var 157 return VariablePartialWidth(trk1,trk2) / VariableWidth(trk1,trk2);
158 } 158 }
159 159
160 G4double G4XAnnihilationChannel::VariableWidth 160 G4double G4XAnnihilationChannel::VariableWidth(const G4KineticTrack& trk1,
161 161 const G4KineticTrack& trk2) const
162 { 162 {
163 // actual production width of resonance, dep 163 // actual production width of resonance, depending on available energy.
164 164
165 G4double width = resonance->GetPDGWidth(); 165 G4double width = resonance->GetPDGWidth();
166 G4bool dummy = false; 166 G4bool dummy = false;
167 G4double sqrtS = (trk1.Get4Momentum() + trk2 167 G4double sqrtS = (trk1.Get4Momentum() + trk2.Get4Momentum()).mag();
168 if (widthTable != 0) 168 if (widthTable != 0)
169 { 169 {
170 width = widthTable->GetValue(sqrtS,dummy 170 width = widthTable->GetValue(sqrtS,dummy);
171 } 171 }
172 return width; 172 return width;
173 } 173 }
174 174
175 175
176 G4double G4XAnnihilationChannel::VariableParti 176 G4double G4XAnnihilationChannel::VariablePartialWidth(const G4KineticTrack& trk1,
177 177 const G4KineticTrack& trk2) const
178 { 178 {
179 // Calculate mass dependent partial width of 179 // Calculate mass dependent partial width of resonance,
180 // based on UrQMD tabulations 180 // based on UrQMD tabulations
181 181
182 G4double width(0); 182 G4double width(0);
183 183
184 if (partWidthTable != 0) 184 if (partWidthTable != 0)
185 { 185 {
186 G4double sqrtS = 0; 186 G4double sqrtS = 0;
187 G4bool dummy = false; 187 G4bool dummy = false;
188 sqrtS = (trk1.Get4Momentum() + trk2.Get4Mo 188 sqrtS = (trk1.Get4Momentum() + trk2.Get4Momentum()).mag();
189 width = partWidthTable->GetValue(sqrtS,dum 189 width = partWidthTable->GetValue(sqrtS,dummy);
190 } 190 }
191 else 191 else
192 { 192 {
193 width = resonance->GetPDGWidth(); 193 width = resonance->GetPDGWidth();
194 } 194 }
195 return width; 195 return width;
196 } 196 }
197 197
198 198
199 G4double G4XAnnihilationChannel::NormalizedCle 199 G4double G4XAnnihilationChannel::NormalizedClebsch(const G4KineticTrack& trk1,
200 200 const G4KineticTrack& trk2) const
201 { 201 {
202 G4double cleb = 0.; 202 G4double cleb = 0.;
203 const G4ParticleDefinition* def1 = trk1.GetD 203 const G4ParticleDefinition* def1 = trk1.GetDefinition();
204 const G4ParticleDefinition* def2 = trk2.GetD 204 const G4ParticleDefinition* def2 = trk2.GetDefinition();
205 205
206 G4int iso31 = def1->GetPDGiIsospin3(); 206 G4int iso31 = def1->GetPDGiIsospin3();
207 G4int iso32 = def2->GetPDGiIsospin3(); 207 G4int iso32 = def2->GetPDGiIsospin3();
208 G4int iso3 = iso31 + iso32; 208 G4int iso3 = iso31 + iso32;
209 G4int iso1 = def1->GetPDGiIsospin(); 209 G4int iso1 = def1->GetPDGiIsospin();
210 G4int iso2 = def2->GetPDGiIsospin(); 210 G4int iso2 = def2->GetPDGiIsospin();
211 211
212 G4int isoRes = resonance->GetPDGiIsospin(); 212 G4int isoRes = resonance->GetPDGiIsospin();
213 213
214 if (isoRes < iso3) return 0.; 214 if (isoRes < iso3) return 0.;
215 if ((iso1*iso2) == 0) return 1.; 215 if ((iso1*iso2) == 0) return 1.;
216 216
217 cleb = clebsch.NormalizedClebschGordan(isoRe 217 cleb = clebsch.NormalizedClebschGordan(isoRes,iso3,iso1,iso2,iso31,iso32);
218 218
219 // Special case: particle-antiparticle, char 219 // Special case: particle-antiparticle, charge-conjugated states have the same weight
220 G4String type1 = def1->GetParticleType(); 220 G4String type1 = def1->GetParticleType();
221 G4String type2 = def2->GetParticleType(); 221 G4String type2 = def2->GetParticleType();
222 G4int anti = def1->GetPDGEncoding() * def2-> 222 G4int anti = def1->GetPDGEncoding() * def2->GetPDGEncoding();
223 G4int strangeness = resonance->GetQuarkConte 223 G4int strangeness = resonance->GetQuarkContent(3) + resonance->GetAntiQuarkContent(3);
224 if ( ((type1 == "baryon" && type2 == "baryon 224 if ( ((type1 == "baryon" && type2 == "baryon") ||(type1 == "meson" && type2 == "meson")) &&
225 anti < 0 && strangeness == 0) 225 anti < 0 && strangeness == 0)
226 { 226 {
227 if (def1->GetPDGEncoding() != -(def2->Ge 227 if (def1->GetPDGEncoding() != -(def2->GetPDGEncoding())) cleb = 0.5 * cleb;
228 } 228 }
229 229
230 return cleb; 230 return cleb;
231 } 231 }
232 232
233 233
234 234
235 235
236 236
237 237