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25 // 25 //
26 26
27 #include "G4StrawTubeXTRadiator.hh" 27 #include "G4StrawTubeXTRadiator.hh"
28 28
29 #include "G4Gamma.hh" 29 #include "G4Gamma.hh"
30 #include "G4PhysicalConstants.hh" 30 #include "G4PhysicalConstants.hh"
31 #include "G4SystemOfUnits.hh" 31 #include "G4SystemOfUnits.hh"
32 32
33 ////////////////////////////////////////////// 33 ////////////////////////////////////////////////////////////////////////////
34 // Constructor, destructor 34 // Constructor, destructor
35 G4StrawTubeXTRadiator::G4StrawTubeXTRadiator(G 35 G4StrawTubeXTRadiator::G4StrawTubeXTRadiator(G4LogicalVolume* anEnvelope,
36 G 36 G4Material* foilMat,
37 G 37 G4Material* gasMat, G4double a,
38 G 38 G4double b, G4Material* mediumMat,
39 G 39 G4bool unishut,
40 c 40 const G4String& processName)
41 : G4VXTRenergyLoss(anEnvelope, foilMat, gasM 41 : G4VXTRenergyLoss(anEnvelope, foilMat, gasMat, a, b, 1, processName)
42 { 42 {
43 if(verboseLevel > 0) 43 if(verboseLevel > 0)
44 G4cout << "Straw tube X-ray TR radiator E 44 G4cout << "Straw tube X-ray TR radiator EM process is called" << G4endl;
45 45
46 if(unishut) 46 if(unishut)
47 { 47 {
48 fAlphaPlate = 1. / 3.; 48 fAlphaPlate = 1. / 3.;
49 fAlphaGas = 12.4; 49 fAlphaGas = 12.4;
50 if(verboseLevel > 0) 50 if(verboseLevel > 0)
51 G4cout << "straw uniform shooting: " 51 G4cout << "straw uniform shooting: "
52 << "fAlphaPlate = " << fAlphaPlat 52 << "fAlphaPlate = " << fAlphaPlate
53 << " ; fAlphaGas = " << fAlphaGas 53 << " ; fAlphaGas = " << fAlphaGas << G4endl;
54 } 54 }
55 else 55 else
56 { 56 {
57 fAlphaPlate = 0.5; 57 fAlphaPlate = 0.5;
58 fAlphaGas = 5.; 58 fAlphaGas = 5.;
59 if(verboseLevel > 0) 59 if(verboseLevel > 0)
60 G4cout << "straw isotropical shooting: " 60 G4cout << "straw isotropical shooting: "
61 << "fAlphaPlate = " << fAlphaPlat 61 << "fAlphaPlate = " << fAlphaPlate
62 << " ; fAlphaGas = " << fAlphaGas 62 << " ; fAlphaGas = " << fAlphaGas << G4endl;
63 } 63 }
64 64
65 // index of medium material 65 // index of medium material
66 fMatIndex3 = (G4int)mediumMat->GetIndex(); 66 fMatIndex3 = (G4int)mediumMat->GetIndex();
67 if(verboseLevel > 0) 67 if(verboseLevel > 0)
68 G4cout << "medium material = " << mediumMa 68 G4cout << "medium material = " << mediumMat->GetName() << G4endl;
69 69
70 // plasma energy squared for plate material 70 // plasma energy squared for plate material
71 fSigma3 = fPlasmaCof * mediumMat->GetElectro 71 fSigma3 = fPlasmaCof * mediumMat->GetElectronDensity();
72 if(verboseLevel > 0) 72 if(verboseLevel > 0)
73 G4cout << "medium plasma energy = " << std 73 G4cout << "medium plasma energy = " << std::sqrt(fSigma3) / eV << " eV"
74 << G4endl; 74 << G4endl;
75 75
76 // Compute cofs for preparation of linear ph 76 // Compute cofs for preparation of linear photo absorption in external medium
77 ComputeMediumPhotoAbsCof(); 77 ComputeMediumPhotoAbsCof();
78 } 78 }
79 79
80 ////////////////////////////////////////////// 80 ///////////////////////////////////////////////////////////////////////////
81 G4StrawTubeXTRadiator::~G4StrawTubeXTRadiator( 81 G4StrawTubeXTRadiator::~G4StrawTubeXTRadiator() = default;
82 82
83 void G4StrawTubeXTRadiator::ProcessDescription 83 void G4StrawTubeXTRadiator::ProcessDescription(std::ostream& out) const
84 { 84 {
85 out << "Simulation of forward X-ray transiti 85 out << "Simulation of forward X-ray transition radiation for the case of\n"
86 "a straw tube radiator.\n"; 86 "a straw tube radiator.\n";
87 } 87 }
88 88
89 ////////////////////////////////////////////// 89 ///////////////////////////////////////////////////////////////////////////
90 // Approximation for radiator interference fac 90 // Approximation for radiator interference factor for the case of
91 // straw tube radiator. The plate (window, str 91 // straw tube radiator. The plate (window, straw wall) and gas (inside straw)
92 // gap thicknesses are gamma distributed. 92 // gap thicknesses are gamma distributed.
93 // The mean values of the plate and gas gap th 93 // The mean values of the plate and gas gap thicknesses
94 // are supposed to be about XTR formation zone 94 // are supposed to be about XTR formation zone.
95 G4double G4StrawTubeXTRadiator::GetStackFactor 95 G4double G4StrawTubeXTRadiator::GetStackFactor(G4double energy, G4double gamma,
96 96 G4double varAngle)
97 { 97 {
98 G4double result, L2, L3, M2, M3; 98 G4double result, L2, L3, M2, M3;
99 99
100 L2 = GetPlateFormationZone(energy, gamma, va 100 L2 = GetPlateFormationZone(energy, gamma, varAngle);
101 L3 = GetGasFormationZone(energy, gamma, varA 101 L3 = GetGasFormationZone(energy, gamma, varAngle);
102 102
103 M2 = GetPlateLinearPhotoAbs(energy); 103 M2 = GetPlateLinearPhotoAbs(energy);
104 M3 = GetGasLinearPhotoAbs(energy); 104 M3 = GetGasLinearPhotoAbs(energy);
105 105
106 G4complex C2(1.0 + 0.5 * fPlateThick * M2 / 106 G4complex C2(1.0 + 0.5 * fPlateThick * M2 / fAlphaPlate,
107 fPlateThick / L2 / fAlphaPlate) 107 fPlateThick / L2 / fAlphaPlate);
108 G4complex C3(1.0 + 0.5 * fGasThick * M3 / fA 108 G4complex C3(1.0 + 0.5 * fGasThick * M3 / fAlphaGas,
109 fGasThick / L3 / fAlphaGas); 109 fGasThick / L3 / fAlphaGas);
110 110
111 G4complex H2 = std::pow(C2, -fAlphaPlate); 111 G4complex H2 = std::pow(C2, -fAlphaPlate);
112 G4complex H3 = std::pow(C3, -fAlphaGas); 112 G4complex H3 = std::pow(C3, -fAlphaGas);
113 G4complex H = H2 * H3; 113 G4complex H = H2 * H3;
114 114
115 G4complex Z1 = GetMediumComplexFZ(energy, ga 115 G4complex Z1 = GetMediumComplexFZ(energy, gamma, varAngle);
116 G4complex Z2 = GetPlateComplexFZ(energy, gam 116 G4complex Z2 = GetPlateComplexFZ(energy, gamma, varAngle);
117 G4complex Z3 = GetGasComplexFZ(energy, gamma 117 G4complex Z3 = GetGasComplexFZ(energy, gamma, varAngle);
118 118
119 G4complex R = (Z1 - Z2) * (Z1 - Z2) * (1. - 119 G4complex R = (Z1 - Z2) * (Z1 - Z2) * (1. - H2 * H) +
120 (Z2 - Z3) * (Z2 - Z3) * (1. - 120 (Z2 - Z3) * (Z2 - Z3) * (1. - H3) +
121 2. * (Z1 - Z2) * (Z2 - Z3) * H 121 2. * (Z1 - Z2) * (Z2 - Z3) * H2 * (1. - H3);
122 122
123 result = 2.0 * std::real(R) * (varAngle * en 123 result = 2.0 * std::real(R) * (varAngle * energy / hbarc / hbarc);
124 124
125 return result; 125 return result;
126 } 126 }
127 127
128 ////////////////////////////////////////////// 128 ////////////////////////////////////////////////////////////////////////
129 // Calculates formation zone for external medi 129 // Calculates formation zone for external medium. Omega is energy !!!
130 G4double G4StrawTubeXTRadiator::GetMediumForma 130 G4double G4StrawTubeXTRadiator::GetMediumFormationZone(G4double omega,
131 131 G4double gamma,
132 132 G4double varAngle)
133 { 133 {
134 G4double cof, lambda; 134 G4double cof, lambda;
135 lambda = 1.0 / gamma / gamma + varAngle + fS 135 lambda = 1.0 / gamma / gamma + varAngle + fSigma3 / omega / omega;
136 cof = 2.0 * hbarc / omega / lambda; 136 cof = 2.0 * hbarc / omega / lambda;
137 return cof; 137 return cof;
138 } 138 }
139 139
140 ////////////////////////////////////////////// 140 ////////////////////////////////////////////////////////////////////////
141 // Calculates complex formation zone for exter 141 // Calculates complex formation zone for external medium. Omega is energy !!!
142 G4complex G4StrawTubeXTRadiator::GetMediumComp 142 G4complex G4StrawTubeXTRadiator::GetMediumComplexFZ(G4double omega,
143 143 G4double gamma,
144 144 G4double varAngle)
145 { 145 {
146 G4double cof, length, delta, real_v, image_v 146 G4double cof, length, delta, real_v, image_v;
147 147
148 length = 0.5 * GetMediumFormationZone(omega, 148 length = 0.5 * GetMediumFormationZone(omega, gamma, varAngle);
149 delta = length * GetMediumLinearPhotoAbs(om 149 delta = length * GetMediumLinearPhotoAbs(omega);
150 cof = 1.0 / (1.0 + delta * delta); 150 cof = 1.0 / (1.0 + delta * delta);
151 151
152 real_v = length * cof; 152 real_v = length * cof;
153 image_v = real_v * delta; 153 image_v = real_v * delta;
154 154
155 G4complex zone(real_v, image_v); 155 G4complex zone(real_v, image_v);
156 return zone; 156 return zone;
157 } 157 }
158 158
159 ////////////////////////////////////////////// 159 ////////////////////////////////////////////////////////////////////////
160 // Computes matrix of Sandia photo absorption 160 // Computes matrix of Sandia photo absorption cross section coefficients for
161 // medium material 161 // medium material
162 void G4StrawTubeXTRadiator::ComputeMediumPhoto 162 void G4StrawTubeXTRadiator::ComputeMediumPhotoAbsCof()
163 { 163 {
164 const G4MaterialTable* theMaterialTable = G4 164 const G4MaterialTable* theMaterialTable = G4Material::GetMaterialTable();
165 const G4Material* mat = (* 165 const G4Material* mat = (*theMaterialTable)[fMatIndex3];
166 fMediumPhotoAbsCof = ma 166 fMediumPhotoAbsCof = mat->GetSandiaTable();
167 } 167 }
168 168
169 ////////////////////////////////////////////// 169 //////////////////////////////////////////////////////////////////////
170 // Returns the value of linear photo absorptio 170 // Returns the value of linear photo absorption coefficient (in reciprocal
171 // length) for medium for given energy of X-ra 171 // length) for medium for given energy of X-ray photon omega
172 G4double G4StrawTubeXTRadiator::GetMediumLinea 172 G4double G4StrawTubeXTRadiator::GetMediumLinearPhotoAbs(G4double omega)
173 { 173 {
174 G4double omega2, omega3, omega4; 174 G4double omega2, omega3, omega4;
175 175
176 omega2 = omega * omega; 176 omega2 = omega * omega;
177 omega3 = omega2 * omega; 177 omega3 = omega2 * omega;
178 omega4 = omega2 * omega2; 178 omega4 = omega2 * omega2;
179 179
180 const G4double* SandiaCof = 180 const G4double* SandiaCof =
181 fMediumPhotoAbsCof->GetSandiaCofForMateria 181 fMediumPhotoAbsCof->GetSandiaCofForMaterial(omega);
182 182
183 G4double cross = SandiaCof[0] / omega + Sand 183 G4double cross = SandiaCof[0] / omega + SandiaCof[1] / omega2 +
184 SandiaCof[2] / omega3 + San 184 SandiaCof[2] / omega3 + SandiaCof[3] / omega4;
185 return cross; 185 return cross;
186 } 186 }
187 187