| Geant4 Cross Reference |
1 // 1
2 // *******************************************
3 // * License and Disclaimer
4 // *
5 // * The Geant4 software is copyright of th
6 // * the Geant4 Collaboration. It is provided
7 // * conditions of the Geant4 Software License
8 // * LICENSE and available at http://cern.ch/
9 // * include a list of copyright holders.
10 // *
11 // * Neither the authors of this software syst
12 // * institutes,nor the agencies providing fin
13 // * work make any representation or warran
14 // * regarding this software system or assum
15 // * use. Please see the license in the file
16 // * for the full disclaimer and the limitatio
17 // *
18 // * This code implementation is the result
19 // * technical work of the GEANT4 collaboratio
20 // * By using, copying, modifying or distri
21 // * any work based on the software) you ag
22 // * use in resulting scientific publicati
23 // * acceptance of all terms of the Geant4 Sof
24 // *******************************************
25 //
26 // -------------------------------------------
27 // GEANT 4 class header file
28 //
29 // History:
30 // 17 August 2004 P. Gumplinger, T. MacP
31 // 11 April 2008 Kamil Sedlak (PSI), To
32 // -------------------------------------------
33 //
34 #include "G4DecayWithSpin.hh"
35
36 #include "G4Step.hh"
37 #include "G4Track.hh"
38 #include "G4DecayTable.hh"
39 #include "G4MuonDecayChannelWithSpin.hh"
40
41 #include "G4PhysicalConstants.hh"
42 #include "G4SystemOfUnits.hh"
43 #include "G4Vector3D.hh"
44
45 #include "G4TransportationManager.hh"
46 #include "G4PropagatorInField.hh"
47 #include "G4FieldManager.hh"
48 #include "G4Field.hh"
49
50 #include "G4Transform3D.hh"
51
52 G4DecayWithSpin::G4DecayWithSpin(const G4Strin
53 {
54 // set Process Sub Type
55 SetProcessSubType(static_cast<int>(DECAY_Wit
56
57 }
58
59 G4DecayWithSpin::~G4DecayWithSpin(){}
60
61 G4VParticleChange* G4DecayWithSpin::PostStepDo
62 {
63 if ( (aTrack.GetTrackStatus() == fStopButAli
64 (aTrack.GetTrackStatus() == fStopAndKil
65 fParticleChangeForDecay.Initialize(aTrack)
66 return &fParticleChangeForDecay;
67 }
68
69 // get particle
70 const G4DynamicParticle* aParticle = aTrack.
71 const G4ParticleDefinition* aParticleDef = a
72
73 // get parent_polarization
74 G4ThreeVector parent_polarization = aParticl
75
76 if(parent_polarization == G4ThreeVector(0,0,
77 // Generate random polarization direction
78 G4double cost = 1. - 2.*G4UniformRand();
79 G4double sint = std::sqrt((1.-cost)*(1.+co
80
81 G4double phi = twopi*G4UniformRand();
82 G4double sinp = std::sin(phi);
83 G4double cosp = std::cos(phi);
84
85 G4double px = sint*cosp;
86 G4double py = sint*sinp;
87 G4double pz = cost;
88
89 parent_polarization.setX(px);
90 parent_polarization.setY(py);
91 parent_polarization.setZ(pz);
92 }
93
94 // decay table
95 G4DecayTable *decaytable = aParticleDef->Get
96 if (decaytable != nullptr) {
97 for (G4int ip=0; ip<decaytable->entries();
98 decaytable->GetDecayChannel(ip)->SetPola
99 }
100 }
101
102 G4ParticleChangeForDecay* pParticleChangeFor
103 pParticleChangeForDecay = (G4ParticleChangeF
104 pParticleChangeForDecay->ProposePolarization
105
106 return pParticleChangeForDecay;
107 }
108
109 G4VParticleChange* G4DecayWithSpin::AtRestDoIt
110 {
111
112 // get particle
113 const G4DynamicParticle* aParticle = aTrack.
114 const G4ParticleDefinition* aParticleDef = a
115
116 // get parent_polarization
117 G4ThreeVector parent_polarization = aParticl
118
119 if(parent_polarization == G4ThreeVector(0,0,
120 // Generate random polarization direction
121 G4double cost = 1. - 2.*G4UniformRand();
122 G4double sint = std::sqrt((1.-cost)*(1.+co
123
124 G4double phi = twopi*G4UniformRand();
125 G4double sinp = std::sin(phi);
126 G4double cosp = std::cos(phi);
127
128 G4double px = sint*cosp;
129 G4double py = sint*sinp;
130 G4double pz = cost;
131
132 parent_polarization.setX(px);
133 parent_polarization.setY(py);
134 parent_polarization.setZ(pz);
135
136 }else{
137
138 G4FieldManager* fieldMgr = aStep.GetTrack(
139 GetLogica
140 if (fieldMgr == nullptr) {
141 G4TransportationManager *transportMgr =
142 G4TransportationManag
143 G4PropagatorInField* fFieldPropagator =
144 transp
145 if (fFieldPropagator) fieldMgr =
146 fFieldPropag
147 }
148
149 const G4Field* field = nullptr;
150 if (fieldMgr != nullptr) field = fieldMgr-
151
152 if ( field != nullptr ) {
153 G4double point[4];
154 point[0] = (aStep.GetPostStepPoint()->G
155 point[1] = (aStep.GetPostStepPoint()->G
156 point[2] = (aStep.GetPostStepPoint()->G
157 point[3] = aTrack.GetGlobalTime();
158
159 G4double fieldValue[6] ={ 0., 0., 0., 0
160 field -> GetFieldValue(point,fieldValue
161 G4ThreeVector B(fieldValue[0],fieldValu
162
163 // Call the spin precession only for no
164 if (B.mag2() > 0.) parent_polarization
165 Spin_Precessi
166
167 }
168 }
169
170 // decay table
171 G4DecayTable *decaytable = aParticleDef->Get
172 if ( decaytable != nullptr) {
173 for (G4int ip=0; ip<decaytable->entries();
174 decaytable->GetDecayChannel(ip)->SetPola
175 }
176 }
177
178 G4ParticleChangeForDecay* pParticleChangeFor
179 pParticleChangeForDecay = (G4ParticleChangeF
180 pParticleChangeForDecay->ProposePolarization
181
182 return pParticleChangeForDecay;
183
184 }
185
186 G4ThreeVector G4DecayWithSpin::Spin_Precession
187 G4Thre
188 {
189 G4double Bnorm = std::sqrt(sqr(B[0]) + sqr(
190
191 G4double q = aStep.GetTrack()->GetDefinition
192 G4double a = 1.165922e-3;
193 G4double s_omega = 8.5062e+7*rad/(s*kilogaus
194
195 G4double omega = -(q*s_omega)*(1.+a) * Bnorm
196
197 G4double rotationangle = deltatime * omega;
198
199 G4Transform3D SpinRotation = G4Rotate3D(rota
200
201 G4Vector3D Spin = aStep.GetTrack() -> GetPol
202
203 G4Vector3D newSpin = SpinRotation * Spin;
204
205 #ifdef G4VERBOSE
206 if (GetVerboseLevel()>2) {
207 G4double normspin = std::sqrt(Spin*Spin);
208 G4double normnewspin = std::sqrt(newSpin*n
209 //G4double cosalpha = Spin*newSpin/normspi
210 //G4double alpha = std::acos(cosalpha);
211
212 G4cout << "AT REST::: PARAMETERS " << G4en
213 G4cout << "Initial spin : " << Spin << G
214 G4cout << "Delta time : " << deltatime
215 G4cout << "Rotation angle: " << rotationan
216 G4cout << "New spin : " << newSpin <
217 G4cout << "Checked norms : " << normspin <
218 }
219 #endif
220
221 return newSpin;
222
223 }
224
225 void G4DecayWithSpin::ProcessDescription(std::
226 {
227 outFile << GetProcessName()
228 << ": Decay of particles considering paren
229 << "kinematics of daughters are dertermine
230 }
231