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