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25 //
26 //
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28 //
29 // -------------------------------------------
30 // GEANT 4 class implementation file
31 //
32 // History: first implementation, based o
33 // 2nd December 1995, G.Cosmo
34 // 7 July 1996 H.Kurashige
35 // -------------------------------------------
36 // remove BuildPhysicsTable() 28 Nov. 1997
37 // change DBL_EPSIRON to DBL_MIN 14 Dec. 19
38 // modified for new ParticleChange 12 Mar. 1
39 // modified for "GoodForTrackingFlag" 19 Jun
40 // rename thePhysicsTable to aPhyscisTable 2
41 // modified IsApplicable in order to protect
42 // to resonances 12 Dec. 1998 H.Kurashi
43 // remove G4ParticleMomentum 6 Feb. 99 H.Ku
44 // modified IsApplicable to activate G4Deca
45 // Add External Decayer 23 Feb. 2001
46 // change LowestBinValue,HighestBinValue and
47 //
48
49 #include "G4Decay.hh"
50
51 #include "G4PhysicalConstants.hh"
52 #include "G4SystemOfUnits.hh"
53 #include "G4DynamicParticle.hh"
54 #include "G4DecayProducts.hh"
55 #include "G4DecayTable.hh"
56 #include "G4VDecayChannel.hh"
57 #include "G4PhysicsLogVector.hh"
58 #include "G4ParticleChangeForDecay.hh"
59 #include "G4VExtDecayer.hh"
60
61 // constructor
62 G4Decay::G4Decay(const G4String& processName)
63 :G4VRestDiscret
64 verboseLevel(1),
65 HighestValue(2
66 fRemainderLifeTime(-1.0),
67 pExtDecayer(nu
68 {
69 // set Process Sub Type
70 SetProcessSubType(static_cast<int>(DECAY));
71
72 #ifdef G4VERBOSE
73 if (GetVerboseLevel()>1) {
74 G4cout << "G4Decay constructor " << " Na
75 }
76 #endif
77
78 pParticleChange = &fParticleChangeForDecay;
79 }
80
81 G4Decay::~G4Decay()
82 {
83 if (pExtDecayer != nullptr) {
84 delete pExtDecayer;
85 }
86 }
87
88 G4bool G4Decay::IsApplicable(const G4ParticleD
89 {
90 // check if the particle is stable?
91 if (aParticleType.GetPDGLifeTime() <0.0) {
92 return false;
93 } else if (aParticleType.GetPDGMass() <= 0.
94 return false;
95 } else {
96 return true;
97 }
98 }
99
100 G4double G4Decay::GetMeanLifeTime(const G4Trac
101 G4ForceCondi
102 {
103 // returns the mean free path in GEANT4 int
104 G4double meanlife;
105
106 // get particle
107 const G4DynamicParticle* aParticle = aTrack
108 const G4ParticleDefinition* aParticleDef =
109 G4double aLife = aParticleDef->GetPDGLifeTi
110
111 // check if the particle is stable?
112 if (aParticleDef->GetPDGStable()) {
113 //1000000 times the life time of the unive
114 meanlife = 1e24 * s;
115
116 } else {
117 meanlife = aLife;
118 }
119
120 #ifdef G4VERBOSE
121 if (GetVerboseLevel()>1) {
122 G4cout << "mean life time: "<< meanlife/n
123 }
124 #endif
125
126 return meanlife;
127 }
128
129 G4double G4Decay::GetMeanFreePath(const G4Trac
130 {
131 // get particle
132 const G4DynamicParticle* aParticle = aTrack
133 const G4ParticleDefinition* aParticleDef =
134 G4double aMass = aParticle->GetMass();
135 G4double aLife = aParticleDef->GetPDGLifeTi
136
137
138 // returns the mean free path in GEANT4 in
139 G4double pathlength;
140 G4double aCtau = c_light * aLife;
141
142 // check if the particle is stable?
143 if (aParticleDef->GetPDGStable()) {
144 pathlength = DBL_MAX;
145
146 //check if the particle has very short life
147 } else if (aCtau < DBL_MIN) {
148 pathlength = DBL_MIN;
149
150 } else {
151 //calculate the mean free path
152 // by using normalized kinetic energy (= E
153 G4double rKineticEnergy = aParticle->Ge
154 if ( rKineticEnergy > HighestValue) {
155 // gamma >> 1
156 pathlength = ( rKineticEnergy + 1.0)* a
157 } else if ( rKineticEnergy < DBL_MIN ) {
158 // too slow particle
159 #ifdef G4VERBOSE
160 if (GetVerboseLevel()>1) {
161 G4cout << "G4Decay::GetMeanFreePath() !!p
162 G4cout << aParticleDef->GetParticleNa
163 G4cout << "KineticEnergy:" << aParticle->Ge
164 }
165 #endif
166 pathlength = DBL_MIN;
167 } else {
168 // beta <1
169 pathlength = (aParticle->GetTotalMoment
170 }
171 }
172 return pathlength;
173 }
174
175 void G4Decay::BuildPhysicsTable(const G4Partic
176 {
177 return;
178 }
179
180 G4VParticleChange* G4Decay::DecayIt(const G4Tr
181 {
182 // The DecayIt() method returns by pointer a
183 // Units are expressed in GEANT4 internal un
184
185 // Initialize ParticleChange
186 // all members of G4VParticleChange are
187 // corresponding member in G4Track
188 fParticleChangeForDecay.Initialize(aTrack);
189
190 // get particle
191 const G4DynamicParticle* aParticle = aTrack.
192 const G4ParticleDefinition* aParticleDef = a
193
194 // check if the particle is stable
195 if (aParticleDef->GetPDGStable()) return &fP
196
197
198 //check if thePreAssignedDecayProducts exist
199 const G4DecayProducts* o_products = (aPartic
200 G4bool isPreAssigned = (o_products != nullpt
201 G4DecayProducts* products = nullptr;
202
203 // decay table
204 G4DecayTable *decaytable = aParticleDef->G
205
206 // check if external decayer exists
207 G4bool isExtDecayer = (decaytable == nullptr
208
209 // Error due to NO Decay Table
210 if ( (decaytable == nullptr) && !isExtDecaye
211 if (GetVerboseLevel()>0) {
212 G4cout << "G4Decay::DoIt : decay table
213 G4cout << aParticle->GetDefinition()->Ge
214 }
215 G4ExceptionDescription ed;
216 ed << "For " << aParticle->GetDefinition()
217 << " decay probability exist but decay
218 << "- the particle will be killed;\n"
219 << " isExtDecayer: " << isExtDecayer
220 << "; isPreAssigned: " << isPreAssigned
221 G4Exception( "G4Decay::DecayIt ",
222 "DECAY101",JustWarning, ed);
223
224 fParticleChangeForDecay.SetNumberOfSeconda
225 // Kill the parent particle
226 fParticleChangeForDecay.ProposeTrackStatus
227 fParticleChangeForDecay.ProposeLocalEnergy
228
229 ClearNumberOfInteractionLengthLeft();
230 return &fParticleChangeForDecay ;
231 }
232
233 if (isPreAssigned) {
234 // copy decay products
235 products = new G4DecayProducts(*o_products
236 } else if ( isExtDecayer ) {
237 // decay according to external decayer
238 products = pExtDecayer->ImportDecayProduct
239 } else {
240 // Decay according to decay table.
241 // Keep trying to choose a candidate decay
242 // of the decaying particle is below the s
243 // candidate daughter particles.
244 // This is needed because the decay table
245 // the assumption of nominal PDG masses, b
246 // a dynamic masses well below its nominal
247 // some of its decay channels can be below
248 // Note that, for simplicity, we ignore he
249 // one or more of the candidate daughter p
250 // wide resonance. However, if this is the
251 // accepted, then the masses of the resona
252 // be sampled by taking into account their
253 G4VDecayChannel* decaychannel = nullptr;
254 G4double massParent = aParticle->GetMass()
255 decaychannel = decaytable->SelectADecayCha
256 if ( decaychannel == nullptr) {
257 // decay channel not found
258 G4ExceptionDescription ed;
259 ed << "Can not determine decay channel f
260 << aParticleDef->GetParticleName() << G4end
261 << " mass of dynamic particle: "
262 << massParent/GeV << " (GEV)" << G4endl
263 << " dacay table has " << decaytable->entr
264 << " entries" << G4endl;
265 G4double checkedmass=massParent;
266 if (massParent < 0.) {
267 checkedmass=aParticleDef->GetPDGMass();
268 ed << "Using PDG mass ("<<checkedmass/GeV
269 << "(GeV)) in IsOKWithParentMass" << G4en
270 }
271 for (G4int ic =0;ic <decaytable->entries
272 G4VDecayChannel * dc= decaytable->GetDecayCh
273 ed << ic << ": BR " << dc->GetBR() << ", IsO
274 << dc->IsOKWithParentMass(checkedmass)
275 << ", --> ";
276 G4int ndaughters=dc->GetNumberOfDaughters();
277 for (G4int id=0;id<ndaughters;++id) {
278 if (id>0) ed << " + "; // seperator, exc
279 ed << dc->GetDaughterName(id);
280 }
281 ed << G4endl;
282 }
283 G4Exception("G4Decay::DoIt", "DECAY003",
284 } else {
285 // execute DecayIt()
286 #ifdef G4VERBOSE
287 G4int temp = decaychannel->GetVerboseLev
288 if (GetVerboseLevel()>1) {
289 G4cout << "G4Decay::DoIt : selected decay c
290 << decaychannel <<G4endl;
291 decaychannel->SetVerboseLevel(GetVerboseLeve
292 }
293 #endif
294 products = decaychannel->DecayIt(aPartic
295 #ifdef G4VERBOSE
296 if (GetVerboseLevel()>1) {
297 decaychannel->SetVerboseLevel(temp);
298 }
299 #endif
300 #ifdef G4VERBOSE
301 if (GetVerboseLevel()>2) {
302 if (! products->IsChecked() ) products->Dump
303 }
304 #endif
305 }
306 }
307
308 // get parent particle information .........
309 G4double ParentEnergy = aParticle->GetTot
310 G4double ParentMass = aParticle->GetMas
311 if (ParentEnergy < ParentMass) {
312 G4ExceptionDescription ed;
313 ed << "Total Energy is less than its mass
314 << "\n Particle: " << aParticle->GetDef
315 << "\n Energy:" << ParentEnergy/MeV
316 << "\n Mass:" << ParentMass/MeV <<
317 G4Exception( "G4Decay::DecayIt ",
318 "DECAY102",JustWarning, ed);
319 ParentEnergy = ParentMass;
320 }
321
322 G4ThreeVector ParentDirection(aParticle->Get
323
324 //boost all decay products to laboratory fra
325 G4double energyDeposit = 0.0;
326 G4double finalGlobalTime = aTrack.GetGlobalT
327 G4double finalLocalTime = aTrack.GetLocalTim
328 if (aTrack.GetTrackStatus() == fStopButAlive
329 // AtRest case
330 finalGlobalTime += fRemainderLifeTime;
331 finalLocalTime += fRemainderLifeTime;
332 energyDeposit += aParticle->GetKineticEner
333 if (isPreAssigned) products->Boost( Parent
334 } else {
335 // PostStep case
336 if (!isExtDecayer) products->Boost( Parent
337 }
338 // set polarization for daughter particles
339 DaughterPolarization(aTrack, products);
340
341
342 //add products in fParticleChangeForDecay
343 G4int numberOfSecondaries = products->entrie
344 fParticleChangeForDecay.SetNumberOfSecondari
345 #ifdef G4VERBOSE
346 if (GetVerboseLevel()>1) {
347 G4cout << "G4Decay::DoIt : Decay vertex :
348 G4cout << " Time: " << finalGlobalTime/ns
349 G4cout << " X:" << (aTrack.GetPosition()).
350 G4cout << " Y:" << (aTrack.GetPosition()).
351 G4cout << " Z:" << (aTrack.GetPosition()).
352 G4cout << G4endl;
353 G4cout << "G4Decay::DoIt : decay products
354 products->DumpInfo();
355 }
356 #endif
357 G4int index;
358 G4ThreeVector currentPosition;
359 const G4TouchableHandle thand = aTrack.GetTo
360 for (index=0; index < numberOfSecondaries; i
361 // get current position of the track
362 currentPosition = aTrack.GetPosition();
363 // create a new track object
364 G4Track* secondary = new G4Track( products
365 finalGlobalTime ,
366 currentPosition );
367 // switch on good for tracking flag
368 secondary->SetGoodForTrackingFlag();
369 secondary->SetTouchableHandle(thand);
370 // add the secondary track in the List
371 fParticleChangeForDecay.AddSecondary(secon
372 }
373 delete products;
374
375 // Kill the parent particle
376 fParticleChangeForDecay.ProposeTrackStatus(
377 fParticleChangeForDecay.ProposeLocalEnergyDe
378 fParticleChangeForDecay.ProposeLocalTime( fi
379
380 // Clear NumberOfInteractionLengthLeft
381 ClearNumberOfInteractionLengthLeft();
382
383 return &fParticleChangeForDecay ;
384 }
385
386 void G4Decay::DaughterPolarization(const G4Tra
387 {
388 // empty implementation
389 }
390
391
392
393 void G4Decay::StartTracking(G4Track*)
394 {
395 currentInteractionLength = -1.0;
396 ResetNumberOfInteractionLengthLeft();
397
398 fRemainderLifeTime = -1.0;
399 }
400
401 void G4Decay::EndTracking()
402 {
403 // Clear NumberOfInteractionLengthLeft
404 ClearNumberOfInteractionLengthLeft();
405
406 currentInteractionLength = -1.0;
407 }
408
409
410 G4double G4Decay::PostStepGetPhysicalInteracti
411 const G4Track& tr
412 G4double previo
413 G4ForceCondition*
414 )
415 {
416 // condition is set to "Not Forced"
417 *condition = NotForced;
418
419 // pre-assigned Decay time
420 G4double pTime = track.GetDynamicParticle()-
421 G4double aLife = track.GetDynamicParticle()-
422
423 if (pTime < 0.) {
424 // normal case
425 if ( previousStepSize > 0.0){
426 // subtract NumberOfInteractionLengthLef
427 SubtractNumberOfInteractionLengthLeft(pr
428 if(theNumberOfInteractionLengthLeft<0.){
429 theNumberOfInteractionLengthLeft=perMillion;
430 }
431 fRemainderLifeTime = theNumberOfInteract
432 }
433 // get mean free path
434 currentInteractionLength = GetMeanFreePath
435
436 #ifdef G4VERBOSE
437 if ((currentInteractionLength <=0.0) || (v
438 G4cout << "G4Decay::PostStepGetPhysicalI
439 track.GetDynamicParticle()->DumpInfo();
440 G4cout << " in Material " << track.GetM
441 G4cout << "MeanFreePath = " << currentIn
442 }
443 #endif
444
445 G4double value;
446 if (currentInteractionLength <DBL_MAX) {
447 value = theNumberOfInteractionLengthLeft
448 //fRemainderLifeTime = theNumberOfIntera
449 } else {
450 value = DBL_MAX;
451 }
452
453 return value;
454
455 } else {
456 //pre-assigned Decay time case
457 // reminder proper time
458 fRemainderLifeTime = pTime - track.GetProp
459 if (fRemainderLifeTime <= 0.0) fRemainderL
460
461 G4double rvalue=0.0;
462 // use pre-assigned Decay time to determin
463 if (aLife>0.0) {
464 // ordinary particle
465 rvalue = (fRemainderLifeTime/aLife)*GetM
466 } else {
467 // shortlived particle
468 rvalue = c_light * fRemainderLifeTime;
469 // by using normalized kinetic energy (=
470 G4double aMass = track.GetDynamicParti
471 rvalue *= track.GetDynamicParticle()->Get
472 }
473 return rvalue;
474 }
475 }
476
477 G4double G4Decay::AtRestGetPhysicalInteraction
478 const G4Track& tr
479 G4ForceCondition*
480 )
481 {
482 // condition is set to "Not Forced"
483 *condition = NotForced;
484
485 G4double pTime = track.GetDynamicParticle()-
486 if (pTime >= 0.) {
487 fRemainderLifeTime = pTime - track.GetProp
488 if (fRemainderLifeTime <= 0.0) fRemainderL
489 } else {
490 fRemainderLifeTime =
491 theNumberOfInteractionLengthLeft * GetMe
492 }
493 return fRemainderLifeTime;
494 }
495
496
497 void G4Decay::SetExtDecayer(G4VExtDecayer* val
498 {
499 pExtDecayer = val;
500
501 // set Process Sub Type
502 if ( pExtDecayer !=0 ) {
503 SetProcessSubType(static_cast<int>(DECAY_E
504 }
505 }
506
507 G4VParticleChange* G4Decay::PostStepDoIt(
508 const G4Track& aTrack,
509 const G4Step& aStep
510 )
511 {
512 if ( (aTrack.GetTrackStatus() == fStopButAli
513 (aTrack.GetTrackStatus() == fStopAndKil
514 fParticleChangeForDecay.Initialize(aTrack)
515 return &fParticleChangeForDecay;
516 } else {
517 return DecayIt(aTrack, aStep);
518 }
519 }
520
521 void G4Decay::ProcessDescription(std::ostream&
522 {
523 outFile << GetProcessName() << ": Decay of p
524 << "kinematics of daughters are dertermine
525 << " or by PreAssignedDecayProducts\
526 }
527