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 implementation file 28 // 29 // History: first implementation, 30 // 21-5-98 V.Grichine 31 // 28-05-01, V.Ivanchenko minor changes t 32 // 04.03.05, V.Grichine: get local field 33 // 18-05-06 H. Burkhardt: Energy spectrum 34 // 35 ////////////////////////////////////////////// 36 37 #include "G4SynchrotronRadiation.hh" 38 39 #include "G4DipBustGenerator.hh" 40 #include "G4Electron.hh" 41 #include "G4EmProcessSubType.hh" 42 #include "G4Log.hh" 43 #include "G4LossTableManager.hh" 44 #include "G4Gamma.hh" 45 #include "G4PhysicalConstants.hh" 46 #include "G4PropagatorInField.hh" 47 #include "G4SystemOfUnits.hh" 48 #include "G4TransportationManager.hh" 49 #include "G4UnitsTable.hh" 50 #include "G4PhysicsModelCatalog.hh" 51 52 ////////////////////////////////////////////// 53 // Constructor 54 G4SynchrotronRadiation::G4SynchrotronRadiation 55 56 : G4VDiscreteProcess(processName, type) 57 , theGamma(G4Gamma::Gamma()) 58 { 59 G4TransportationManager* transportMgr = 60 G4TransportationManager::GetTransportation 61 62 fFieldPropagator = transportMgr->GetPropagat 63 64 secID = G4PhysicsModelCatalog::GetModelID("m 65 SetProcessSubType(fSynchrotronRadiation); 66 verboseLevel = 1; 67 FirstTime = true; 68 FirstTime1 = true; 69 genAngle = nullptr; 70 SetAngularGenerator(new G4DipBustGenerator() 71 theManager = G4LossTableManager::Instance(); 72 theManager->Register(this); 73 } 74 75 ////////////////////////////////////////////// 76 // Destructor 77 G4SynchrotronRadiation::~G4SynchrotronRadiatio 78 { 79 delete genAngle; 80 theManager->DeRegister(this); 81 } 82 83 /////////////////////////////// METHODS ////// 84 85 void G4SynchrotronRadiation::SetAngularGenerat 86 { 87 if(p != genAngle) 88 { 89 delete genAngle; 90 genAngle = p; 91 } 92 } 93 94 G4bool G4SynchrotronRadiation::IsApplicable( 95 const G4ParticleDefinition& particle) 96 { 97 return (particle.GetPDGCharge() != 0.0 && !p 98 } 99 100 ////////////////////////////////////////////// 101 // Production of synchrotron X-ray photon 102 // Geant4 internal units. 103 G4double G4SynchrotronRadiation::GetMeanFreePa 104 105 106 { 107 // gives the MeanFreePath in Geant4 internal 108 G4double MeanFreePath = DBL_MAX; 109 110 const G4DynamicParticle* aDynamicParticle = 111 112 *condition = NotForced; 113 114 G4double gamma = 115 aDynamicParticle->GetTotalEnergy() / aDyna 116 117 G4double particleCharge = aDynamicParticle-> 118 119 if(gamma < 1.0e3 || 0.0 == particleCharge) 120 { 121 MeanFreePath = DBL_MAX; 122 } 123 else 124 { 125 G4ThreeVector FieldValue; 126 const G4Field* pField = nullptr; 127 G4bool fieldExertsForce = false; 128 129 G4FieldManager* fieldMgr = 130 fFieldPropagator->FindAndSetFieldManager 131 132 if(fieldMgr != nullptr) 133 { 134 // If the field manager has no field, th 135 fieldExertsForce = (fieldMgr->GetDetecto 136 } 137 138 if(fieldExertsForce) 139 { 140 pField = fieldMgr->G 141 G4ThreeVector globPosition = trackData.G 142 143 G4double globPosVec[4], FieldValueVec[6] 144 145 globPosVec[0] = globPosition.x(); 146 globPosVec[1] = globPosition.y(); 147 globPosVec[2] = globPosition.z(); 148 globPosVec[3] = trackData.GetGlobalTime( 149 150 pField->GetFieldValue(globPosVec, FieldV 151 152 FieldValue = 153 G4ThreeVector(FieldValueVec[0], FieldV 154 155 G4ThreeVector unitMomentum = aDynamicPar 156 G4ThreeVector unitMcrossB = FieldValue. 157 G4double perpB = unitMcrossB 158 159 static const G4double fLambdaConst = 160 std::sqrt(3.0) * eplus / (2.5 * fine_s 161 162 if(perpB > 0.0) 163 { 164 MeanFreePath = fLambdaConst * 165 aDynamicParticle->GetDe 166 (perpB * particleCharge 167 } 168 if(verboseLevel > 0 && FirstTime) 169 { 170 G4cout << "G4SynchrotronRadiation::Get 171 << " for particle " 172 << aDynamicParticle->GetDefinit 173 << '\n' 174 << " MeanFreePath = " << G4Bes 175 << G4endl; 176 if(verboseLevel > 1) 177 { 178 G4ThreeVector pvec = aDynamicParticl 179 G4double Btot = FieldValue.getR 180 G4double ptot = pvec.getR(); 181 G4double rho = ptot / (MeV * c 182 // full bending radius 183 G4double Theta = unitMomentum.theta( 184 // angle between particle and field 185 G4cout << " B = " << Btot / tesla < 186 << " perpB = " << perpB / te 187 << " Theta = " << Theta 188 << " std::sin(Theta)=" << std 189 << " ptot = " << G4BestUnit 190 << " rho = " << G4BestUnit 191 } 192 FirstTime = false; 193 } 194 } 195 } 196 return MeanFreePath; 197 } 198 199 ////////////////////////////////////////////// 200 G4VParticleChange* G4SynchrotronRadiation::Pos 201 const G4Track& trackData, const G4Step& step 202 203 { 204 aParticleChange.Initialize(trackData); 205 206 const G4DynamicParticle* aDynamicParticle = 207 208 G4double gamma = aDynamicParticle->GetTotalE 209 (aDynamicParticle->GetDefin 210 211 G4double particleCharge = aDynamicParticle-> 212 if(gamma <= 1.0e3 || 0.0 == particleCharge) 213 { 214 return G4VDiscreteProcess::PostStepDoIt(tr 215 } 216 217 G4ThreeVector FieldValue; 218 const G4Field* pField = nullptr; 219 220 G4bool fieldExertsForce = false; 221 G4FieldManager* fieldMgr = 222 fFieldPropagator->FindAndSetFieldManager(t 223 224 if(fieldMgr != nullptr) 225 { 226 // If the field manager has no field, ther 227 fieldExertsForce = (fieldMgr->GetDetectorF 228 } 229 230 if(fieldExertsForce) 231 { 232 pField = fieldMgr->Get 233 G4ThreeVector globPosition = trackData.Get 234 G4double globPosVec[4], FieldValueVec[6]; 235 globPosVec[0] = globPosition.x(); 236 globPosVec[1] = globPosition.y(); 237 globPosVec[2] = globPosition.z(); 238 globPosVec[3] = trackData.GetGlobalTime(); 239 240 pField->GetFieldValue(globPosVec, FieldVal 241 FieldValue = 242 G4ThreeVector(FieldValueVec[0], FieldVal 243 244 G4ThreeVector unitMomentum = aDynamicParti 245 G4ThreeVector unitMcrossB = FieldValue.cr 246 G4double perpB = unitMcrossB.m 247 if(perpB > 0.0) 248 { 249 // M-C of synchrotron photon energy 250 G4double energyOfSR = GetRandomEnergySR( 251 gamma, perpB, aDynamicParticle->GetDef 252 253 // check against insufficient energy 254 if(energyOfSR <= 0.0) 255 { 256 return G4VDiscreteProcess::PostStepDoI 257 } 258 G4double kineticEnergy = aDynamicParticl 259 G4ThreeVector gammaDirection = 260 genAngle->SampleDirection(aDynamicPart 261 262 G4ThreeVector gammaPolarization = FieldV 263 gammaPolarization = gammaP 264 265 // create G4DynamicParticle object for t 266 auto aGamma = 267 new G4DynamicParticle(theGamma, gammaD 268 aGamma->SetPolarization(gammaPolarizatio 269 gammaPolarizatio 270 271 aParticleChange.SetNumberOfSecondaries(1 272 273 // Update the incident particle 274 G4double newKinEnergy = kineticEnergy - 275 276 if(newKinEnergy > 0.) 277 { 278 aParticleChange.ProposeEnergy(newKinEn 279 } 280 else 281 { 282 aParticleChange.ProposeEnergy(0.); 283 } 284 285 // Create the G4Track 286 G4Track* aSecondaryTrack = new G4Track(a 287 aSecondaryTrack->SetTouchableHandle(step 288 aSecondaryTrack->SetParentID(trackData.G 289 aSecondaryTrack->SetCreatorModelID(secID 290 aParticleChange.AddSecondary(aSecondaryT 291 292 } 293 } 294 return G4VDiscreteProcess::PostStepDoIt(trac 295 } 296 297 ////////////////////////////////////////////// 298 G4double G4SynchrotronRadiation::InvSynFracInt 299 // direct generation 300 { 301 // from 0 to 0.7 302 static constexpr G4double aa1 = 0; 303 static constexpr G4double aa2 = 0. 304 static constexpr G4int ncheb1 = 27 305 static constexpr G4double cheb1[ncheb1] = { 306 1.22371665676046468821, 0.108956475422 307 0.0383328524358594396134, 0.007591383693 308 0.00205712048644963340914, 0.000497810783 309 0.000130743691810302187818, 0.000033816876 310 8.97049680900520817728e-6, 2.386854727944 311 6.41923109149104165049e-7, 1.735498989827 312 4.72145949240790029153e-8, 1.290398661119 313 3.5422080787089834182e-9, 9.759475733640 314 2.6979510184976065731e-10, 7.480422622550 315 2.079598176402699913e-11, 5.795336222208 316 1.61856011449276096e-12, 4.529450993473 317 1.2698603951096606e-13, 3.566117394511 318 1.00301587494091e-14, 2.825153464472 319 7.9680747949792e-16 320 }; 321 // from 0.7 to 0.9132260271183847 322 static constexpr G4double aa3 = 0. 323 static constexpr G4int ncheb2 = 27 324 static constexpr G4double cheb2[ncheb2] = { 325 1.1139496701107756, 0.3523967429328067 326 0.01475818043595387, 0.0033812556373224 327 0.00020785506681254216, 0.0000539016925370 328 3.823880733161044e-6, 1.0381966089136036 329 7.86223332179956e-8, 2.1866609342508474 330 1.7191233618437565e-9, 4.852755117740807e 331 3.908961987062447e-11, 1.1146253766895824 332 9.134319791300977e-13, 2.6211077371181566 333 2.1528376972619e-14, 6.030906040404772e 334 }; 335 // Chebyshev with exp/log scale 336 // a = -Log[1 - SynFracInt[1]]; b = -Log[1 - 337 static constexpr G4double aa4 = 2. 338 static constexpr G4double aa5 = 9. 339 static constexpr G4int ncheb3 = 28 340 static constexpr G4double cheb3[ncheb3] = { 341 1.2292683840435586977, 0.1603534492 342 -0.0353559911947559448721, 0.0077690156 343 -0.00165886451971685133259, 0.0003357191 344 -0.0000617184951079161143187, 9.2353403974 345 -6.06747198795168022842e-7, -3.079340459 346 1.98818772614682367781e-7, -8.139099715 347 2.84298174969641838618e-8, -9.128297666 348 2.77713868004820551077e-9, -8.130327672 349 2.31128525568385247392e-10, -6.417968732 350 1.74815310473323361543e-11, -4.686535369 351 1.24016595805520752748e-12, -3.248394329 352 8.44601465226513952994e-14, -2.186472760 353 5.65407548745690689978e-15, -1.465536259 354 3.82059606377570462276e-16, -1.004578966 355 }; 356 static constexpr G4double aa6 = 33 357 static constexpr G4int ncheb4 = 27 358 static constexpr G4double cheb4[ncheb4] = { 359 1.69342658227676741765, 0.07427664008 360 -0.019337880608635717358, 0.00516065527 361 -0.00139342012990307729473, 0.00037854986 362 -0.000103167085583785340215, 0.00002815434 363 -7.68409742018258198651e-6, 2.09543221890 364 -5.70493140367526282946e-7, 1.54961164548 365 -4.19665599629607704794e-8, 1.13239680054 366 -3.04223563379021441863e-9, 8.13073745977 367 -2.15969415476814981374e-10, 5.69472105972 368 -1.48844799572430829499e-11, 3.84901514438 369 -9.82222575944247161834e-13, 2.46468329208 370 -6.04953826265982691612e-14, 1.44055805710 371 -3.28200813577388740722e-15, 6.96566359173 372 -1.294122794852896275e-16 373 }; 374 375 if(x < aa2) 376 return x * x * x * Chebyshev(aa1, aa2, che 377 else if(x < aa3) 378 return Chebyshev(aa2, aa3, cheb2, ncheb2, 379 else if(x < 1 - 0.0000841363) 380 { 381 G4double y = -G4Log(1 - x); 382 return y * Chebyshev(aa4, aa5, cheb3, nche 383 } 384 else 385 { 386 G4double y = -G4Log(1 - x); 387 return y * Chebyshev(aa5, aa6, cheb4, nche 388 } 389 } 390 391 G4double G4SynchrotronRadiation::GetRandomEner 392 393 394 { 395 static const G4double fEnergyConst = 396 1.5 * c_light * c_light * eplus * hbar_Pla 397 G4double Ecr = fEnergyConst * gamma * gamma 398 399 if(verboseLevel > 0 && FirstTime1) 400 { 401 // mean and rms of photon energy 402 G4double Emean = 8. / (15. * std::sqrt(3.) 403 G4double E_rms = std::sqrt(211. / 675.) * 404 G4long prec = G4cout.precision(); 405 G4cout << "G4SynchrotronRadiation::GetRand 406 << std::setprecision(4) << " Ecr 407 << '\n' 408 << " Emean = " << G4BestUnit(Emean 409 << " E_rms = " << G4BestUnit(E_rms 410 FirstTime1 = false; 411 G4cout.precision(prec); 412 } 413 414 G4double energySR = Ecr * InvSynFracInt(G4Un 415 return energySR; 416 } 417 418 ////////////////////////////////////////////// 419 void G4SynchrotronRadiation::BuildPhysicsTable 420 { 421 if(0 < verboseLevel && &part == G4Electron:: 422 ProcessDescription(G4cout); 423 // same for all particles, print only for on 424 } 425 426 ////////////////////////////////////////////// 427 void G4SynchrotronRadiation::ProcessDescriptio 428 { 429 out << GetProcessName() 430 << ": Incoherent Synchrotron Radiation\ 431 "Good description for long magnets at 432 } 433