| 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 // $Id: G4Generator2BS.cc,v 1.10 2010-10-14 14:01:02 vnivanch Exp $
>> 27 // GEANT4 tag $Name: not supported by cvs2svn $
26 // 28 //
27 // ------------------------------------------- 29 // -------------------------------------------------------------------
28 // 30 //
29 // GEANT4 Class file 31 // GEANT4 Class file
30 // 32 //
31 // 33 //
32 // File name: G4Generator2BS 34 // File name: G4Generator2BS
33 // 35 //
34 // Author: Andreia Trindade (andreia@li 36 // Author: Andreia Trindade (andreia@lip.pt)
35 // Pedro Rodrigues (psilva@lip 37 // Pedro Rodrigues (psilva@lip.pt)
36 // Luis Peralta (luis@lip.p 38 // Luis Peralta (luis@lip.pt)
37 // 39 //
38 // Creation date: 2 June 2003 40 // Creation date: 2 June 2003
39 // 41 //
40 // Modifications: 42 // Modifications:
41 // 02 Jun 2003 First implementat 43 // 02 Jun 2003 First implementation acording with new design
42 // 05 Nov 2003 MGP Fixed std namespa 44 // 05 Nov 2003 MGP Fixed std namespace
43 // 17 Nov 2003 MGP Fixed compilation 45 // 17 Nov 2003 MGP Fixed compilation problem on Windows
44 // 12 Oct 2010 V.Ivanchenko Moved RejectionFu 46 // 12 Oct 2010 V.Ivanchenko Moved RejectionFunction inline, use G4Pow to speadup
45 // 09 May 2011 L.Pandola Initialize privat <<
46 // 47 //
47 // Class Description: 48 // Class Description:
48 // 49 //
49 // Concrete base class for Bremsstrahlung Angu 50 // Concrete base class for Bremsstrahlung Angular Distribution Generation
50 // 2BS Distribution 51 // 2BS Distribution
51 // 52 //
52 // Class Description: End 53 // Class Description: End
53 // 54 //
54 // ------------------------------------------- 55 // -------------------------------------------------------------------
55 // 56 //
56 57
57 #include "G4Generator2BS.hh" 58 #include "G4Generator2BS.hh"
58 #include "Randomize.hh" 59 #include "Randomize.hh"
59 #include "G4PhysicalConstants.hh" <<
60 #include "G4SystemOfUnits.hh" <<
61 #include "G4Pow.hh" 60 #include "G4Pow.hh"
62 61
>> 62 //
>> 63
63 G4Generator2BS::G4Generator2BS(const G4String& 64 G4Generator2BS::G4Generator2BS(const G4String&)
64 : G4VEmAngularDistribution("AngularGen2BS"), << 65 : G4VBremAngularDistribution("AngularGen2BS")
65 ratio1(1.),ratio2(1.),delta(0.) <<
66 { 66 {
67 g4pow = G4Pow::GetInstance(); 67 g4pow = G4Pow::GetInstance();
68 nwarn = 0; <<
69 } 68 }
70 69
>> 70 //
>> 71
71 G4Generator2BS::~G4Generator2BS() 72 G4Generator2BS::~G4Generator2BS()
72 {} 73 {}
73 74
74 G4ThreeVector& G4Generator2BS::SampleDirection << 75 //
75 G4double final_energy, << 76
76 G4int Z, << 77 G4double G4Generator2BS::PolarAngle(const G4double initial_energy,
77 const G4Material*) << 78 const G4double final_energy,
>> 79 const G4int Z)
78 { 80 {
>> 81
79 // Adapted from "Improved bremsstrahlung pho 82 // Adapted from "Improved bremsstrahlung photon angular sampling in the EGS4 code system"
80 // by Alex F. Bielajew, Rahde Mohan anc Chen 83 // by Alex F. Bielajew, Rahde Mohan anc Chen-Shou Chui, PIRS-0203
81 // Ionizing Radiation Standards 84 // Ionizing Radiation Standards
82 // Institute for National Measurement Standa 85 // Institute for National Measurement Standards
83 // National Research Council of Canada 86 // National Research Council of Canada
84 // Departement of Medical Physics, Memorial 87 // Departement of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York
85 88
86 G4double energy = dp->GetTotalEnergy(); << 89 G4double theta = 0;
87 ratio = final_energy/energy; << 90
88 ratio1 = (1 + ratio)*(1 + ratio); << 91 G4double initialTotalEnergy = (initial_energy+electron_mass_c2)/electron_mass_c2;
89 ratio2 = 1 + ratio*ratio; << 92 G4double finalTotalEnergy = (final_energy+electron_mass_c2)/electron_mass_c2;
>> 93 EnergyRatio = finalTotalEnergy/initialTotalEnergy;
>> 94 G4double gMaxEnergy = (pi*initialTotalEnergy)*(pi*initialTotalEnergy);
90 95
91 G4double gamma = energy/electron_mass_c2; << 96 //G4double Zeff = std::sqrt(static_cast<G4double>(Z) * (static_cast<G4double>(Z) + 1.0));
92 G4double beta = std::sqrt((gamma - 1)*(gamm << 97 //z = (0.00008116224*(std::pow(Zeff,0.3333333)));
93 98
94 // VI speadup 99 // VI speadup
95 fz = 0.00008116224*g4pow->Z13(Z)*g4pow->Z13( << 100 z = 0.00008116224*(g4pow->Z13(Z) + g4pow->Z13(Z+1));
96 101
97 // majoranta << 102 // Rejection arguments
98 G4double ymax = 2*beta*(1 + beta)*gamma*gamm << 103 rejection_argument1 = (1.0+EnergyRatio*EnergyRatio);
99 G4double gMax = RejectionFunction(0.0); << 104 rejection_argument2 = - 2.0*EnergyRatio + 3.0*rejection_argument1;
100 gMax = std::max(gMax,RejectionFunction(ymax) << 105 rejection_argument3 = ((1-EnergyRatio)/(2.0*initialTotalEnergy*EnergyRatio))*
>> 106 ((1-EnergyRatio)/(2.0*initialTotalEnergy*EnergyRatio));
>> 107
>> 108 // Calculate rejection function at 0, 1 and Emax
>> 109 G4double gfunction0 = RejectionFunction(0.0);
>> 110 G4double gfunction1 = RejectionFunction(1.0);
>> 111 G4double gfunctionEmax = RejectionFunction(gMaxEnergy);
>> 112
>> 113 // Calculate Maximum value
>> 114 G4double gMaximum = std::max(gfunction0,gfunction1);
>> 115 gMaximum = std::max(gMaximum,gfunctionEmax);
101 116
102 G4double y, gfun; << 117 G4double rand, gfunctionTest, randTest;
103 118
104 do{ 119 do{
105 G4double q = G4UniformRand(); << 120 rand = G4UniformRand();
106 y = q*ymax/(1 + ymax*(1 - q)); << 121 rand /= (1 - rand + 1.0/gMaxEnergy);
107 gfun = RejectionFunction(y); << 122 gfunctionTest = RejectionFunction(rand);
108 << 123 randTest = G4UniformRand();
109 // violation point << 124
110 if(gfun > gMax && nwarn >= 20) { << 125 } while(randTest*gMaximum > gfunctionTest);
111 ++nwarn; <<
112 G4cout << "### WARNING in G4Generator2BS <<
113 << " Egamma(MeV)" << (energy - final_e <<
114 << " gMax= " << gMax << " < " << gfun <<
115 << " results are not reliable!" <<
116 << G4endl; <<
117 if(20 == nwarn) { <<
118 G4cout << " WARNING in G4Generator2BS is c <<
119 } <<
120 } <<
121 <<
122 } while(G4UniformRand()*gMax > gfun || y > y <<
123 <<
124 G4double cost = 1 - 2*y/ymax; <<
125 G4double sint = std::sqrt((1 - cost)*(1 + co <<
126 G4double phi = twopi*G4UniformRand(); <<
127 126
128 fLocalDirection.set(sint*std::cos(phi), sint << 127 theta = std::sqrt(rand)/initialTotalEnergy;
129 fLocalDirection.rotateUz(dp->GetMomentumDire <<
130 128
131 return fLocalDirection; << 129 return theta;
132 } 130 }
>> 131
>> 132 //
133 133
134 void G4Generator2BS::PrintGeneratorInformation 134 void G4Generator2BS::PrintGeneratorInformation() const
135 { 135 {
136 G4cout << "\n" << G4endl; 136 G4cout << "\n" << G4endl;
137 G4cout << "Bremsstrahlung Angular Generator 137 G4cout << "Bremsstrahlung Angular Generator is 2BS Generator "
138 << "from 2BS Koch & Motz distribution (Rev 138 << "from 2BS Koch & Motz distribution (Rev Mod Phys 31(4), 920 (1959))" << G4endl;
139 G4cout << "Sampling algorithm adapted from P 139 G4cout << "Sampling algorithm adapted from PIRS-0203" << G4endl;
140 G4cout << "\n" << G4endl; 140 G4cout << "\n" << G4endl;
141 } 141 }
142 142
143 143