1 | // |
---|
2 | // ******************************************************************** |
---|
3 | // * License and Disclaimer * |
---|
4 | // * * |
---|
5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
7 | // * conditions of the Geant4 Software License, included in the file * |
---|
8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
9 | // * include a list of copyright holders. * |
---|
10 | // * * |
---|
11 | // * Neither the authors of this software system, nor their employing * |
---|
12 | // * institutes,nor the agencies providing financial support for this * |
---|
13 | // * work make any representation or warranty, express or implied, * |
---|
14 | // * regarding this software system or assume any liability for its * |
---|
15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
16 | // * for the full disclaimer and the limitation of liability. * |
---|
17 | // * * |
---|
18 | // * This code implementation is the result of the scientific and * |
---|
19 | // * technical work of the GEANT4 collaboration. * |
---|
20 | // * By using, copying, modifying or distributing the software (or * |
---|
21 | // * any work based on the software) you agree to acknowledge its * |
---|
22 | // * use in resulting scientific publications, and indicate your * |
---|
23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
24 | // ******************************************************************** |
---|
25 | // |
---|
26 | #include "G4ContinuousGainOfEnergy.hh" |
---|
27 | #include "G4Step.hh" |
---|
28 | #include "G4ParticleDefinition.hh" |
---|
29 | #include "G4VEmModel.hh" |
---|
30 | #include "G4VEmFluctuationModel.hh" |
---|
31 | #include "G4VParticleChange.hh" |
---|
32 | #include "G4UnitsTable.hh" |
---|
33 | |
---|
34 | |
---|
35 | /////////////////////////////////////////////////////// |
---|
36 | // |
---|
37 | G4ContinuousGainOfEnergy::G4ContinuousGainOfEnergy(const G4String& name, |
---|
38 | G4ProcessType type): G4VContinuousProcess(name, type) |
---|
39 | { |
---|
40 | |
---|
41 | linLossLimit=0.05; |
---|
42 | lossFluctuationArePossible =true; |
---|
43 | lossFluctuationFlag=true; |
---|
44 | is_integral = false; |
---|
45 | |
---|
46 | } |
---|
47 | |
---|
48 | /////////////////////////////////////////////////////// |
---|
49 | // |
---|
50 | G4ContinuousGainOfEnergy::~G4ContinuousGainOfEnergy() |
---|
51 | { |
---|
52 | |
---|
53 | } |
---|
54 | /////////////////////////////////////////////////////// |
---|
55 | // |
---|
56 | |
---|
57 | void G4ContinuousGainOfEnergy::PreparePhysicsTable( |
---|
58 | const G4ParticleDefinition& ) |
---|
59 | {//theDirectEnergyLossProcess->PreparePhysicsTable(part); |
---|
60 | |
---|
61 | ; |
---|
62 | } |
---|
63 | |
---|
64 | /////////////////////////////////////////////////////// |
---|
65 | // |
---|
66 | |
---|
67 | void G4ContinuousGainOfEnergy::BuildPhysicsTable(const G4ParticleDefinition&) |
---|
68 | {//theDirectEnergyLossProcess->BuildPhysicsTable(part); |
---|
69 | ; |
---|
70 | } |
---|
71 | |
---|
72 | |
---|
73 | |
---|
74 | |
---|
75 | /////////////////////////////////////////////////////// |
---|
76 | // |
---|
77 | // |
---|
78 | G4VParticleChange* G4ContinuousGainOfEnergy::AlongStepDoIt(const G4Track& track, |
---|
79 | const G4Step& step) |
---|
80 | { |
---|
81 | |
---|
82 | aParticleChange.Initialize(track); |
---|
83 | |
---|
84 | // Get the actual (true) Step length |
---|
85 | //---------------------------------- |
---|
86 | G4double length = step.GetStepLength(); |
---|
87 | G4double degain = 0.0; |
---|
88 | |
---|
89 | |
---|
90 | |
---|
91 | |
---|
92 | // Compute this for weight change after continuous energy loss |
---|
93 | //------------------------------------------------------------- |
---|
94 | G4double DEDX_before = |
---|
95 | theDirectEnergyLossProcess |
---|
96 | ->GetDEDX(preStepKinEnergy, currentCouple); |
---|
97 | |
---|
98 | |
---|
99 | |
---|
100 | // For the fluctuation we generate a new dynamic particle with energy =preEnergy+egain |
---|
101 | // and then compute the fluctuation given in the direct case. |
---|
102 | //----------------------------------------------------------------------- |
---|
103 | G4DynamicParticle* dynParticle = new G4DynamicParticle(); |
---|
104 | *dynParticle = *(track.GetDynamicParticle()); |
---|
105 | G4double Tkin = dynParticle->GetKineticEnergy(); |
---|
106 | |
---|
107 | size_t n=1; |
---|
108 | if (is_integral ) n=10; |
---|
109 | G4double dlength= length/n; |
---|
110 | for (size_t i=0;i<n;i++) { |
---|
111 | G4double r = theDirectEnergyLossProcess->GetRange(Tkin, currentCouple); |
---|
112 | if( dlength <= linLossLimit * r ) { |
---|
113 | degain = DEDX_before*dlength; |
---|
114 | } |
---|
115 | else { |
---|
116 | G4double x = r + length; |
---|
117 | degain = theDirectEnergyLossProcess->GetKineticEnergy(x,currentCouple) - theDirectEnergyLossProcess->GetKineticEnergy(r,currentCouple); |
---|
118 | } |
---|
119 | G4VEmModel* currentModel = theDirectEnergyLossProcess->SelectModelForMaterial(Tkin+degain,currentMaterialIndex); |
---|
120 | G4double tmax = currentModel->MaxSecondaryKinEnergy(dynParticle); |
---|
121 | tmax = std::min(tmax,currentTcut); |
---|
122 | |
---|
123 | |
---|
124 | |
---|
125 | // Sample fluctuations |
---|
126 | //------------------- |
---|
127 | |
---|
128 | G4double deltaE =0.; |
---|
129 | if (lossFluctuationFlag ) { |
---|
130 | deltaE = currentModel->GetModelOfFluctuations()-> |
---|
131 | SampleFluctuations(currentMaterial,dynParticle,tmax,length,degain)-degain; |
---|
132 | } |
---|
133 | Tkin+=degain+deltaE; |
---|
134 | dynParticle->SetKineticEnergy(Tkin); |
---|
135 | |
---|
136 | } |
---|
137 | |
---|
138 | |
---|
139 | |
---|
140 | // Corrections, which cannot be tabulated |
---|
141 | // probably this should be also changed |
---|
142 | // at this time it does nothing so we can leave it |
---|
143 | //CorrectionsAlongStep(currentCouple, dynParticle, egain, length); |
---|
144 | |
---|
145 | delete dynParticle; |
---|
146 | |
---|
147 | |
---|
148 | G4double DEDX_after = theDirectEnergyLossProcess->GetDEDX(Tkin, currentCouple); |
---|
149 | G4double weight_correction=DEDX_after/DEDX_before; //probably not needed |
---|
150 | weight_correction=1.; |
---|
151 | |
---|
152 | aParticleChange.ProposeEnergy(Tkin); |
---|
153 | |
---|
154 | //we still need to register in the particleChange the modification of the weight of the particle |
---|
155 | G4double new_weight=weight_correction*track.GetWeight(); |
---|
156 | aParticleChange.SetParentWeightByProcess(true); |
---|
157 | aParticleChange.ProposeParentWeight(new_weight); |
---|
158 | |
---|
159 | |
---|
160 | return &aParticleChange; |
---|
161 | |
---|
162 | } |
---|
163 | /////////////////////////////////////////////////////// |
---|
164 | // |
---|
165 | void G4ContinuousGainOfEnergy::SetLossFluctuations(G4bool val) |
---|
166 | { |
---|
167 | if(val && !lossFluctuationArePossible) return; |
---|
168 | lossFluctuationFlag = val; |
---|
169 | } |
---|