Geant4 Cross Reference |
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 // $Id: G4NuMuNucleusNcModel.cc 91806 2015-08-06 12:20:45Z gcosmo $ 27 // 28 // Geant4 Header : G4NuMuNucleusNcModel 29 // 30 // Author : V.Grichine 12.2.19 31 // 32 33 #include "G4NuMuNucleusNcModel.hh" 34 #include "G4NeutrinoNucleusModel.hh" 35 36 // #include "G4NuMuResQX.hh" 37 38 #include "G4SystemOfUnits.hh" 39 #include "G4ParticleTable.hh" 40 #include "G4ParticleDefinition.hh" 41 #include "G4IonTable.hh" 42 #include "Randomize.hh" 43 #include "G4RandomDirection.hh" 44 45 // #include "G4Integrator.hh" 46 #include "G4DataVector.hh" 47 #include "G4PhysicsTable.hh" 48 #include "G4KineticTrack.hh" 49 #include "G4DecayKineticTracks.hh" 50 #include "G4KineticTrackVector.hh" 51 #include "G4Fragment.hh" 52 #include "G4ReactionProductVector.hh" 53 54 55 #include "G4NeutrinoMu.hh" 56 #include "G4AntiNeutrinoMu.hh" 57 #include "G4Nucleus.hh" 58 #include "G4LorentzVector.hh" 59 60 using namespace std; 61 using namespace CLHEP; 62 63 #ifdef G4MULTITHREADED 64 G4Mutex G4NuMuNucleusNcModel::numuNucleusModel = G4MUTEX_INITIALIZER; 65 #endif 66 67 68 G4NuMuNucleusNcModel::G4NuMuNucleusNcModel(const G4String& name) 69 : G4NeutrinoNucleusModel(name) 70 { 71 SetMinEnergy( 0.0*GeV ); 72 SetMaxEnergy( 100.*TeV ); 73 SetMinEnergy(1.e-6*eV); 74 75 theNuMu = G4NeutrinoMu::NeutrinoMu(); 76 theANuMu = G4AntiNeutrinoMu::AntiNeutrinoMu(); 77 78 fMnumu = 0.; 79 fData = fMaster = false; 80 InitialiseModel(); 81 82 } 83 84 85 G4NuMuNucleusNcModel::~G4NuMuNucleusNcModel() 86 {} 87 88 89 void G4NuMuNucleusNcModel::ModelDescription(std::ostream& outFile) const 90 { 91 92 outFile << "G4NuMuNucleusNcModel is a neutrino-nucleus (neutral current) scattering\n" 93 << "model which uses the standard model \n" 94 << "transfer parameterization. The model is fully relativistic\n"; 95 96 } 97 98 ///////////////////////////////////////////////////////// 99 // 100 // Read data from G4PARTICLEXSDATA (locally PARTICLEXSDATA) 101 102 void G4NuMuNucleusNcModel::InitialiseModel() 103 { 104 G4String pName = "nu_mu"; 105 106 G4int nSize(0), i(0), j(0), k(0); 107 108 if(!fData) 109 { 110 #ifdef G4MULTITHREADED 111 G4MUTEXLOCK(&numuNucleusModel); 112 if(!fData) 113 { 114 #endif 115 fMaster = true; 116 #ifdef G4MULTITHREADED 117 } 118 G4MUTEXUNLOCK(&numuNucleusModel); 119 #endif 120 } 121 122 if(fMaster) 123 { 124 const char* path = G4FindDataDir("G4PARTICLEXSDATA"); 125 std::ostringstream ost1, ost2, ost3, ost4; 126 ost1 << path << "/" << "neutrino" << "/" << pName << "/xarraynckr"; 127 128 std::ifstream filein1( ost1.str().c_str() ); 129 130 // filein.open("$PARTICLEXSDATA/"); 131 132 filein1>>nSize; 133 134 for( k = 0; k < fNbin; ++k ) 135 { 136 for( i = 0; i <= fNbin; ++i ) 137 { 138 filein1 >> fNuMuXarrayKR[k][i]; 139 // G4cout<< fNuMuXarrayKR[k][i] << " "; 140 } 141 } 142 // G4cout<<G4endl<<G4endl; 143 144 ost2 << path << "/" << "neutrino" << "/" << pName << "/xdistrnckr"; 145 std::ifstream filein2( ost2.str().c_str() ); 146 147 filein2>>nSize; 148 149 for( k = 0; k < fNbin; ++k ) 150 { 151 for( i = 0; i < fNbin; ++i ) 152 { 153 filein2 >> fNuMuXdistrKR[k][i]; 154 // G4cout<< fNuMuXdistrKR[k][i] << " "; 155 } 156 } 157 // G4cout<<G4endl<<G4endl; 158 159 ost3 << path << "/" << "neutrino" << "/" << pName << "/q2arraynckr"; 160 std::ifstream filein3( ost3.str().c_str() ); 161 162 filein3>>nSize; 163 164 for( k = 0; k < fNbin; ++k ) 165 { 166 for( i = 0; i <= fNbin; ++i ) 167 { 168 for( j = 0; j <= fNbin; ++j ) 169 { 170 filein3 >> fNuMuQarrayKR[k][i][j]; 171 // G4cout<< fNuMuQarrayKR[k][i][j] << " "; 172 } 173 } 174 } 175 // G4cout<<G4endl<<G4endl; 176 177 ost4 << path << "/" << "neutrino" << "/" << pName << "/q2distrnckr"; 178 std::ifstream filein4( ost4.str().c_str() ); 179 180 filein4>>nSize; 181 182 for( k = 0; k < fNbin; ++k ) 183 { 184 for( i = 0; i <= fNbin; ++i ) 185 { 186 for( j = 0; j < fNbin; ++j ) 187 { 188 filein4 >> fNuMuQdistrKR[k][i][j]; 189 // G4cout<< fNuMuQdistrKR[k][i][j] << " "; 190 } 191 } 192 } 193 fData = true; 194 } 195 } 196 197 ///////////////////////////////////////////////////////// 198 199 G4bool G4NuMuNucleusNcModel::IsApplicable(const G4HadProjectile & aPart, 200 G4Nucleus & ) 201 { 202 G4bool result = false; 203 G4String pName = aPart.GetDefinition()->GetParticleName(); 204 G4double energy = aPart.GetTotalEnergy(); 205 206 if( pName == "nu_mu" // || pName == "anti_nu_mu" ) 207 && 208 energy > fMinNuEnergy ) 209 { 210 result = true; 211 } 212 213 return result; 214 } 215 216 /////////////////////////////////////////// ClusterDecay //////////////////////////////////////////////////////////// 217 // 218 // 219 220 G4HadFinalState* G4NuMuNucleusNcModel::ApplyYourself( 221 const G4HadProjectile& aTrack, G4Nucleus& targetNucleus) 222 { 223 theParticleChange.Clear(); 224 fProton = f2p2h = fBreak = false; 225 const G4HadProjectile* aParticle = &aTrack; 226 G4double energy = aParticle->GetTotalEnergy(); 227 228 G4String pName = aParticle->GetDefinition()->GetParticleName(); 229 230 if( energy < fMinNuEnergy ) 231 { 232 theParticleChange.SetEnergyChange(energy); 233 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 234 return &theParticleChange; 235 } 236 SampleLVkr( aTrack, targetNucleus); 237 238 if( fBreak == true || fEmu < fMnumu ) // ~5*10^-6 239 { 240 // G4cout<<"ni, "; 241 theParticleChange.SetEnergyChange(energy); 242 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 243 return &theParticleChange; 244 } 245 246 // LVs of initial state 247 248 G4LorentzVector lvp1 = aParticle->Get4Momentum(); 249 G4LorentzVector lvt1( 0., 0., 0., fM1 ); 250 G4double mPip = G4ParticleTable::GetParticleTable()->FindParticle(211)->GetPDGMass(); 251 252 // 1-pi by fQtransfer && nu-energy 253 G4LorentzVector lvpip1( 0., 0., 0., mPip ); 254 G4LorentzVector lvsum, lv2, lvX; 255 G4ThreeVector eP; 256 G4double cost(1.), sint(0.), phi(0.), muMom(0.), massX2(0.); 257 G4DynamicParticle* aLept = nullptr; // lepton lv 258 259 G4int Z = targetNucleus.GetZ_asInt(); 260 G4int A = targetNucleus.GetA_asInt(); 261 G4double mTarg = targetNucleus.AtomicMass(A,Z); 262 G4int pdgP(0), qB(0); 263 // G4double mSum = G4ParticleTable::GetParticleTable()->FindParticle(2212)->GetPDGMass() + mPip; 264 265 G4int iPi = GetOnePionIndex(energy); 266 G4double p1pi = GetNuMuOnePionProb( iPi, energy); 267 268 if( p1pi > G4UniformRand() && fCosTheta > 0.9 ) // && fQtransfer < 0.95*GeV ) // mu- & coherent pion + nucleus 269 { 270 // lvsum = lvp1 + lvpip1; 271 lvsum = lvp1 + lvt1; 272 // cost = fCosThetaPi; 273 cost = fCosTheta; 274 sint = std::sqrt( (1.0 - cost)*(1.0 + cost) ); 275 phi = G4UniformRand()*CLHEP::twopi; 276 eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost ); 277 278 // muMom = sqrt(fEmuPi*fEmuPi-fMnumu*fMnumu); 279 muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu); 280 281 eP *= muMom; 282 283 // lv2 = G4LorentzVector( eP, fEmuPi ); 284 lv2 = G4LorentzVector( eP, fEmu ); 285 lv2 = fLVl; 286 287 lvX = lvsum - lv2; 288 lvX = fLVh; 289 massX2 = lvX.m2(); 290 G4double massX = lvX.m(); 291 G4double massR = fLVt.m(); 292 293 // if ( massX2 <= 0. ) // vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved 294 if ( massX2 <= fM1*fM1 ) // 9-3-20 vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved 295 if ( lvX.e() <= fM1 ) // 9-3-20 vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved 296 { 297 theParticleChange.SetEnergyChange(energy); 298 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 299 return &theParticleChange; 300 } 301 fW2 = massX2; 302 303 if( pName == "nu_mu" ) aLept = new G4DynamicParticle( theNuMu, lv2 ); 304 else if( pName == "anti_nu_mu") aLept = new G4DynamicParticle( theANuMu, lv2 ); 305 else 306 { 307 theParticleChange.SetEnergyChange(energy); 308 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 309 return &theParticleChange; 310 } 311 312 pdgP = 111; 313 314 G4double eCut; // = fMpi + 0.5*(fMpi*fMpi - massX2)/mTarg; // massX -> fMpi 315 316 if( A > 1 ) 317 { 318 eCut = (fMpi + mTarg)*(fMpi + mTarg) - (massX + massR)*(massX + massR); 319 eCut /= 2.*massR; 320 eCut += massX; 321 } 322 else eCut = fM1 + fMpi; 323 324 if ( lvX.e() > eCut ) // && sqrt( GetW2() ) < 1.4*GeV ) // 325 { 326 CoherentPion( lvX, pdgP, targetNucleus); 327 } 328 else 329 { 330 theParticleChange.SetEnergyChange(energy); 331 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 332 return &theParticleChange; 333 } 334 theParticleChange.AddSecondary( aLept, fSecID ); 335 336 return &theParticleChange; 337 } 338 else // lepton part in lab 339 { 340 lvsum = lvp1 + lvt1; 341 cost = fCosTheta; 342 sint = std::sqrt( (1.0 - cost)*(1.0 + cost) ); 343 phi = G4UniformRand()*CLHEP::twopi; 344 eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost ); 345 346 muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu); 347 348 eP *= muMom; 349 350 lv2 = G4LorentzVector( eP, fEmu ); 351 352 lvX = lvsum - lv2; 353 354 massX2 = lvX.m2(); 355 356 if ( massX2 <= 0. ) // vmg: very rarely ~ (1-4)e-6 due to big Q2/x, to be improved 357 { 358 theParticleChange.SetEnergyChange(energy); 359 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 360 return &theParticleChange; 361 } 362 fW2 = massX2; 363 364 aLept = new G4DynamicParticle( theNuMu, lv2 ); 365 366 theParticleChange.AddSecondary( aLept, fSecID ); 367 } 368 369 // hadron part 370 371 fRecoil = nullptr; 372 fCascade = false; 373 fString = false; 374 375 if( A == 1 ) 376 { 377 qB = 1; 378 379 // if( G4UniformRand() > 0.1 ) // > 0.9999 ) // > 0.0001 ) // 380 { 381 ClusterDecay( lvX, qB ); 382 } 383 return &theParticleChange; 384 } 385 G4Nucleus recoil; 386 G4double rM(0.), ratio = G4double(Z)/G4double(A); 387 388 if( ratio > G4UniformRand() ) // proton is excited 389 { 390 fProton = true; 391 recoil = G4Nucleus(A-1,Z-1); 392 fRecoil = &recoil; 393 rM = recoil.AtomicMass(A-1,Z-1); 394 395 fMt = G4ParticleTable::GetParticleTable()->FindParticle(2212)->GetPDGMass() 396 + G4ParticleTable::GetParticleTable()->FindParticle(111)->GetPDGMass(); 397 } 398 else // excited neutron 399 { 400 fProton = false; 401 recoil = G4Nucleus(A-1,Z); 402 fRecoil = &recoil; 403 rM = recoil.AtomicMass(A-1,Z); 404 405 fMt = G4ParticleTable::GetParticleTable()->FindParticle(2112)->GetPDGMass() 406 + G4ParticleTable::GetParticleTable()->FindParticle(111)->GetPDGMass(); 407 } 408 // G4int index = GetEnergyIndex(energy); 409 G4int nepdg = aParticle->GetDefinition()->GetPDGEncoding(); 410 411 G4double qeTotRat; // = GetNuMuQeTotRat(index, energy); 412 qeTotRat = CalculateQEratioA( Z, A, energy, nepdg); 413 414 G4ThreeVector dX = (lvX.vect()).unit(); 415 G4double eX = lvX.e(); // excited nucleon 416 G4double mX = sqrt(massX2); 417 418 if( qeTotRat > G4UniformRand() || mX <= fMt ) // || eX <= 1232.*MeV) // QE 419 { 420 fString = false; 421 422 if( fProton ) 423 { 424 fPDGencoding = 2212; 425 fMr = proton_mass_c2; 426 recoil = G4Nucleus(A-1,Z-1); 427 fRecoil = &recoil; 428 rM = recoil.AtomicMass(A-1,Z-1); 429 } 430 else 431 { 432 fPDGencoding = 2112; 433 fMr = G4ParticleTable::GetParticleTable()-> 434 FindParticle(fPDGencoding)->GetPDGMass(); // 939.5654133*MeV; 435 recoil = G4Nucleus(A-1,Z); 436 fRecoil = &recoil; 437 rM = recoil.AtomicMass(A-1,Z); 438 } 439 G4double eTh = fMr+0.5*(fMr*fMr-mX*mX)/rM; 440 441 if(eX <= eTh) // vmg, very rarely out of kinematics 442 { 443 theParticleChange.SetEnergyChange(energy); 444 theParticleChange.SetMomentumChange(aTrack.Get4Momentum().vect().unit()); 445 return &theParticleChange; 446 } 447 FinalBarion( lvX, 0, fPDGencoding ); // p(n)+deexcited recoil 448 } 449 else // if ( eX < 9500000.*GeV ) // < 25.*GeV) // < 95.*GeV ) // < 2.5*GeV ) //cluster decay 450 { 451 if ( fProton && pName == "nu_mu" ) qB = 1; 452 else if( !fProton && pName == "nu_mu" ) qB = 0; 453 454 ClusterDecay( lvX, qB ); 455 } 456 return &theParticleChange; 457 } 458 459 460 ///////////////////////////////////////////////////////////////////// 461 //////////////////////////////////////////////////////////////////// 462 /////////////////////////////////////////////////////////////////// 463 464 ///////////////////////////////////////////////// 465 // 466 // sample x, then Q2 467 468 void G4NuMuNucleusNcModel::SampleLVkr(const G4HadProjectile & aTrack, G4Nucleus& targetNucleus) 469 { 470 fBreak = false; 471 G4int A = targetNucleus.GetA_asInt(), iTer(0), iTerMax(100); 472 G4int Z = targetNucleus.GetZ_asInt(); 473 G4double e3(0.), pMu2(0.), pX2(0.), nMom(0.), rM(0.), hM(0.), tM = targetNucleus.AtomicMass(A,Z); 474 G4double cost(1.), sint(0.), phi(0.), muMom(0.); 475 G4ThreeVector eP, bst; 476 const G4HadProjectile* aParticle = &aTrack; 477 G4LorentzVector lvp1 = aParticle->Get4Momentum(); 478 nMom = NucleonMomentum( targetNucleus ); 479 480 if( A == 1 || nMom == 0. ) // hydrogen, no Fermi motion ??? 481 { 482 fNuEnergy = aParticle->GetTotalEnergy(); 483 iTer = 0; 484 485 do 486 { 487 fXsample = SampleXkr(fNuEnergy); 488 fQtransfer = SampleQkr(fNuEnergy, fXsample); 489 fQ2 = fQtransfer*fQtransfer; 490 491 if( fXsample > 0. ) 492 { 493 fW2 = fM1*fM1 - fQ2 + fQ2/fXsample; // sample excited hadron mass 494 fEmu = fNuEnergy - fQ2/2./fM1/fXsample; 495 } 496 else 497 { 498 fW2 = fM1*fM1; 499 fEmu = fNuEnergy; 500 } 501 e3 = fNuEnergy + fM1 - fEmu; 502 503 // if( e3 < sqrt(fW2) ) G4cout<<"energyX = "<<e3/GeV<<", fW = "<<sqrt(fW2)/GeV<<G4endl; // vmg ~10^-5 for NC 504 505 pMu2 = fEmu*fEmu - fMnumu*fMnumu; 506 pX2 = e3*e3 - fW2; 507 508 fCosTheta = fNuEnergy*fNuEnergy + pMu2 - pX2; 509 fCosTheta /= 2.*fNuEnergy*sqrt(pMu2); 510 iTer++; 511 } 512 while( ( abs(fCosTheta) > 1. || fEmu < fMnumu ) && iTer < iTerMax ); 513 514 if( iTer >= iTerMax ) { fBreak = true; return; } 515 516 if( abs(fCosTheta) > 1.) // vmg: due to big Q2/x values. To be improved ... 517 { 518 G4cout<<"H2: fCosTheta = "<<fCosTheta<<", fEmu = "<<fEmu<<G4endl; 519 // fCosTheta = -1. + 2.*G4UniformRand(); 520 if(fCosTheta < -1.) fCosTheta = -1.; 521 if(fCosTheta > 1.) fCosTheta = 1.; 522 } 523 // LVs 524 525 G4LorentzVector lvt1 = G4LorentzVector( 0., 0., 0., fM1 ); 526 G4LorentzVector lvsum = lvp1 + lvt1; 527 528 cost = fCosTheta; 529 sint = std::sqrt( (1.0 - cost)*(1.0 + cost) ); 530 phi = G4UniformRand()*CLHEP::twopi; 531 eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost ); 532 muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu); 533 eP *= muMom; 534 fLVl = G4LorentzVector( eP, fEmu ); 535 536 fLVh = lvsum - fLVl; 537 fLVt = G4LorentzVector( 0., 0., 0., 0. ); // no recoil 538 } 539 else // Fermi motion, Q2 in nucleon rest frame 540 { 541 G4ThreeVector nMomDir = nMom*G4RandomDirection(); 542 543 if( !f2p2h ) // 1p1h 544 { 545 G4Nucleus recoil(A-1,Z); 546 rM = sqrt( recoil.AtomicMass(A-1,Z)*recoil.AtomicMass(A-1,Z) + nMom*nMom ); 547 hM = tM - rM; 548 549 fLVt = G4LorentzVector( nMomDir, sqrt( rM*rM+nMom*nMom ) ); 550 fLVh = G4LorentzVector(-nMomDir, sqrt( hM*hM+nMom*nMom ) ); 551 } 552 else // 2p2h 553 { 554 G4Nucleus recoil(A-2,Z-1); 555 rM = recoil.AtomicMass(A-2,Z-1)+sqrt(nMom*nMom+fM1*fM1); 556 hM = tM - rM; 557 558 fLVt = G4LorentzVector( nMomDir, sqrt( rM*rM+nMom*nMom ) ); 559 fLVh = G4LorentzVector(-nMomDir, sqrt( hM*hM+nMom*nMom ) ); 560 } 561 // G4cout<<hM<<", "; 562 // bst = fLVh.boostVector(); // 9-3-20 563 564 // lvp1.boost(-bst); // 9-3-20 -> nucleon rest system, where Q2 transfer is ??? 565 566 fNuEnergy = lvp1.e(); 567 iTer = 0; 568 569 do 570 { 571 fXsample = SampleXkr(fNuEnergy); 572 fQtransfer = SampleQkr(fNuEnergy, fXsample); 573 fQ2 = fQtransfer*fQtransfer; 574 575 if( fXsample > 0. ) 576 { 577 fW2 = fM1*fM1 - fQ2 + fQ2/fXsample; // sample excited hadron mass 578 fEmu = fNuEnergy - fQ2/2./fM1/fXsample; 579 } 580 else 581 { 582 fW2 = fM1*fM1; 583 fEmu = fNuEnergy; 584 } 585 586 // if(fEmu < 0.) G4cout<<"fEmu = "<<fEmu<<" hM = "<<hM<<G4endl; 587 588 e3 = fNuEnergy + fM1 - fEmu; 589 590 // if( e3 < sqrt(fW2) ) G4cout<<"energyX = "<<e3/GeV<<", fW = "<<sqrt(fW2)/GeV<<G4endl; 591 592 pMu2 = fEmu*fEmu - fMnumu*fMnumu; 593 pX2 = e3*e3 - fW2; 594 595 fCosTheta = fNuEnergy*fNuEnergy + pMu2 - pX2; 596 fCosTheta /= 2.*fNuEnergy*sqrt(pMu2); 597 iTer++; 598 } 599 while( ( abs(fCosTheta) > 1. || fEmu < fMnumu ) && iTer < iTerMax ); 600 601 if( iTer >= iTerMax ) { fBreak = true; return; } 602 603 if( abs(fCosTheta) > 1.) // vmg: due to big Q2/x values. To be improved ... 604 { 605 G4cout<<"FM: fCosTheta = "<<fCosTheta<<", fEmu = "<<fEmu<<G4endl; 606 // fCosTheta = -1. + 2.*G4UniformRand(); 607 if(fCosTheta < -1.) fCosTheta = -1.; 608 if(fCosTheta > 1.) fCosTheta = 1.; 609 } 610 // LVs 611 G4LorentzVector lvt1 = G4LorentzVector( 0., 0., 0., fM1 ); 612 G4LorentzVector lvsum = lvp1 + lvt1; 613 614 cost = fCosTheta; 615 sint = std::sqrt( (1.0 - cost)*(1.0 + cost) ); 616 phi = G4UniformRand()*CLHEP::twopi; 617 eP = G4ThreeVector( sint*std::cos(phi), sint*std::sin(phi), cost ); 618 muMom = sqrt(fEmu*fEmu-fMnumu*fMnumu); 619 eP *= muMom; 620 fLVl = G4LorentzVector( eP, fEmu ); 621 fLVh = lvsum - fLVl; 622 // back to lab system 623 // fLVl.boost(bst); // 9-3-20 624 // fLVh.boost(bst); // 9-3-20 625 } 626 //G4cout<<iTer<<", "<<fBreak<<"; "; 627 } 628 629 // 630 // 631 /////////////////////////// 632