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G4GoudsmitSaundersonMscModel Class Reference
#include <G4GoudsmitSaundersonMscModel.hh>
Inheritance diagram for G4GoudsmitSaundersonMscModel:
Detailed Description
Definition at line 138 of file G4GoudsmitSaundersonMscModel.hh.
Constructor & Destructor Documentation
◆ G4GoudsmitSaundersonMscModel()
| G4GoudsmitSaundersonMscModel::G4GoudsmitSaundersonMscModel | ( | const G4String & | nam = "GoudsmitSaunderson" | ) |
Definition at line 163 of file G4GoudsmitSaundersonMscModel.cc.
164 : G4VMscModel(nam) {
165 charge = 0;
166 currentMaterialIndex = -1;
167 //
168 fr = 0.1;
169 rangeinit = 1.e+21;
170 geombig = 1.e+50*mm;
171 geomlimit = geombig;
172 tgeom = geombig;
173 tlimit = 1.e+10*mm;
174 presafety = 0.*mm;
175 //
176 particle = 0;
177 theManager = G4LossTableManager::Instance();
178 firstStep = true;
179 currentKinEnergy = 0.0;
180 currentRange = 0.0;
181 //
182 tlimitminfix2 = 1.*nm;
183 tausmall = 1.e-16;
184 mass = electron_mass_c2;
185 taulim = 1.e-6;
186 //
187 currentCouple = nullptr;
188 fParticleChange = nullptr;
189 //
190 fZeff = 1.;
191 //
192 par1 = 0.;
193 par2 = 0.;
194 par3 = 0.;
195 //
196 // Moliere screeing parameter will be used and (by default) corrections are
197 // appalied to the integrated quantities (screeing parameter, elastic mfp, first
198 // and second moments) derived from the corresponding PWA quantities
199 // this PWA correction is ignored if Mott-correction is set to true because
200 // Mott-correction contains all these corrections as well
201 fIsUsePWACorrection = true;
202 //
203 fIsUseMottCorrection = false;
204 //
205 fLambda0 = 0.0; // elastic mean free path
206 fLambda1 = 0.0; // first transport mean free path
207 fScrA = 0.0; // screening parameter
208 fG1 = 0.0; // first transport coef.
209 //
210 fMCtoScrA = 1.0;
211 fMCtoQ1 = 1.0;
212 fMCtoG2PerG1 = 1.0;
213 //
214 fTheTrueStepLenght = 0.;
215 fTheTransportDistance = 0.;
216 fTheZPathLenght = 0.;
217 //
218 fTheDisplacementVector.set(0.,0.,0.);
219 fTheNewDirection.set(0.,0.,1.);
220 //
221 fIsEverythingWasDone = false;
222 fIsMultipleSacettring = false;
223 fIsSingleScattering = false;
224 fIsEndedUpOnBoundary = false;
225 fIsNoScatteringInMSC = false;
226 fIsNoDisplace = false;
227 fIsInsideSkin = false;
228 fIsWasOnBoundary = false;
229 fIsFirstRealStep = false;
230 rndmEngineMod = G4Random::getTheEngine();
231 //
232 fGSTable = nullptr;
233 fPWACorrection = nullptr;
234}
void set(double x, double y, double z)
static G4LossTableManager * Instance()
Definition: G4LossTableManager.cc:87
Definition: G4VMscModel.hh:67
◆ ~G4GoudsmitSaundersonMscModel()
|
virtual |
Definition at line 237 of file G4GoudsmitSaundersonMscModel.cc.
237 {
239 if (fGSTable) {
240 delete fGSTable;
241 fGSTable = nullptr;
242 }
243 if (fPWACorrection) {
244 delete fPWACorrection;
245 fPWACorrection = nullptr;
246 }
247 }
248}
Member Function Documentation
◆ ComputeGeomPathLength()
Implements G4VMscModel.
Definition at line 781 of file G4GoudsmitSaundersonMscModel.cc.
781 {
782 // convert true ->geom
783 // It is called from the step limitation ComputeTruePathLengthLimit if
784 // !fIsEverythingWasDone but protect:
785 par1 = -1.;
786 par2 = par3 = 0.;
787 // if fIsEverythingWasDone = TRUE => fTheZPathLenght is already set
788 // so return with the already known value
789 // Otherwise:
790 if (!fIsEverythingWasDone) {
791 // this correction needed to run MSC with eIoni and eBrem inactivated
792 // and makes no harm for a normal run
793 fTheTrueStepLenght = std::min(fTheTrueStepLenght,currentRange);
794 // do the true -> geom transformation
795 fTheZPathLenght = fTheTrueStepLenght;
796 // z = t for very small true-path-length
797 if (fTheTrueStepLenght<tlimitminfix2) {
798 return fTheZPathLenght;
799 }
800 G4double tau = fTheTrueStepLenght/fLambda1;
801 if (tau<=tausmall) {
802 fTheZPathLenght = std::min(fTheTrueStepLenght, fLambda1);
804 if (tau<taulim) fTheZPathLenght = fTheTrueStepLenght*(1.-0.5*tau) ;
806 } else if (currentKinEnergy<mass || fTheTrueStepLenght==currentRange) {
807 par1 = 1./currentRange ; // alpha =1/range_init for Ekin<mass
808 par2 = 1./(par1*fLambda1) ; // 1/(alphaxlambda01)
809 par3 = 1.+par2 ; // 1+1/
810 if (fTheTrueStepLenght<currentRange) {
811 fTheZPathLenght = 1./(par1*par3) * (1.-std::pow(1.-par1*fTheTrueStepLenght,par3));
812 } else {
813 fTheZPathLenght = 1./(par1*par3);
814 }
815 } else {
816 G4double rfin = std::max(currentRange-fTheTrueStepLenght, 0.01*currentRange);
818 G4double lambda1 = GetTransportMeanFreePathOnly(particle,T1);
819 //
820 par1 = (fLambda1-lambda1)/(fLambda1*fTheTrueStepLenght); // alpha
821 par2 = 1./(par1*fLambda1);
822 par3 = 1.+par2 ;
824 fTheZPathLenght = 1./(par1*par3) * (1.-g4calc->powA(1.-par1*fTheTrueStepLenght,par3));
825 }
826 }
827 fTheZPathLenght = std::min(fTheZPathLenght, fLambda1);
828 //
829 return fTheZPathLenght;
830}
Definition: G4Pow.hh:49
G4double GetEnergy(const G4ParticleDefinition *part, G4double range, const G4MaterialCutsCouple *couple)
Definition: G4VMscModel.hh:368
◆ ComputeTruePathLengthLimit()
|
virtual |
Implements G4VMscModel.
Definition at line 469 of file G4GoudsmitSaundersonMscModel.cc.
470 {
471 G4double skindepth = 0.;
472 //
476 currentCouple = track.GetMaterialCutsCouple();
477 SetCurrentCouple(currentCouple);
479 currentKinEnergy = dp->GetKineticEnergy();
480 currentRange = GetRange(particle,currentKinEnergy,currentCouple,
481 dp->GetLogKineticEnergy());
482 // elastic and first transport mfp, screening parameter and G1 are also set
483 // (Mott-correction will be used if it was requested by the user)
484 fLambda1 = GetTransportMeanFreePath(particle,currentKinEnergy);
485 // Set initial values:
486 // : lengths are initialised to currentMinimalStep which is the true, minimum
487 // step length from all other physics
488 fTheTrueStepLenght = currentMinimalStep;
489 fTheTransportDistance = currentMinimalStep;
490 fTheZPathLenght = currentMinimalStep; // will need to be converted
491 fTheDisplacementVector.set(0.,0.,0.);
492 fTheNewDirection.set(0.,0.,1.);
493
494 // Can everything be done in the step limit phase ?
495 fIsEverythingWasDone = false;
496 // Multiple scattering needs to be sample ?
497 fIsMultipleSacettring = false;
498 // Single scattering needs to be sample ?
499 fIsSingleScattering = false;
500 // Was zero deflection in multiple scattering sampling ?
501 fIsNoScatteringInMSC = false;
502 // Do not care about displacement in MSC sampling
503 // ( used only in the case of gIsOptimizationOn = true)
504 fIsNoDisplace = false;
505 // get pre-step point safety
506 presafety = sp->GetSafety();
507 //
509 // distance will take into account max-fluct.
510 G4double distance = currentRange;
511 distance *= (1.20-fZeff*(1.62e-2-9.22e-5*fZeff));
512 //
513 // Possible optimization : if the distance is samller than the safety -> the
514 // particle will never leave this volume -> dispalcement
515 // as the effect of multiple elastic scattering can be skipped
516 // Important : this optimization can cause problems if one does scoring
517 // in a bigger volume since MSC won't be done deep inside the volume when
518 // distance < safety so don't use optimized-mode in such case.
519 if (gIsOptimizationOn && (distance<presafety)) {
520 // Indicate that we need to do MSC after transportation and no dispalcement.
521 fIsMultipleSacettring = true;
522 fIsNoDisplace = true;
524 //Compute geomlimit (and presafety) :
525 // - geomlimit will be:
526 // == the straight line distance to the boundary if currentRange is
527 // longer than that
528 // == a big value [geombig = 1.e50*mm] if currentRange is shorter than
529 // the straight line distance to the boundary
530 // - presafety will be updated as well
531 // So the particle can travell 'gemlimit' distance (along a straight
532 // line!) in its current direction:
533 // (1) before reaching a boundary (geomlimit < geombig) OR
534 // (2) before reaching its current range (geomlimit == geombig)
535 geomlimit = ComputeGeomLimit(track, presafety, currentRange);
536 // Record that the particle is on a boundary
538 fIsWasOnBoundary = true;
539 }
540 // Set skin depth = skin x elastic_mean_free_path
541 skindepth = skin*fLambda0;
542 // Init the flag that indicates that the particle are within a skindepth
543 // distance from a boundary
544 fIsInsideSkin = false;
545 // Check if we can try Single Scattering because we are within skindepth
546 // distance from/to a boundary OR the current minimum true-step-length is
547 // shorter than skindepth. NOTICE: the latest has only efficieny reasons
548 // because the MSC angular sampling is fine for any short steps but much
549 // faster to try single scattering in case of short steps.
551 // check if we are within skindepth distance from a boundary
553 fIsInsideSkin = true;
554 fIsWasOnBoundary = true;
555 }
556 //Try single scattering:
557 // - sample distance to next single scattering interaction (sslimit)
558 // - compare to current minimum length
559 // == if sslimit is the shorter:
560 // - set the step length to sslimit
561 // - indicate that single scattering needs to be done
562 // == else : nothing to do
563 //- in both cases, the step length was very short so geometrical and
564 // true path length are the same
566 // compare to current minimum step length
567 if (sslimit<fTheTrueStepLenght) {
568 fTheTrueStepLenght = sslimit;
569 fIsSingleScattering = true;
570 }
571 // short step -> true step length equal to geometrical path length
572 fTheZPathLenght = fTheTrueStepLenght;
573 // Set taht everything is done in step-limit phase so no MSC call
574 // We will check if we need to perform the single-scattering angular
575 // sampling i.e. if single elastic scattering was the winer!
576 fIsEverythingWasDone = true;
577 } else {
578 // After checking we know that we cannot try single scattering so we will
579 // need to make an MSC step
580 // Indicate that we need to make and MSC step. We do not check if we can
581 // do it now i.e. if presafety>final_true_step_length so we let the
582 // fIsEverythingWasDone = false which indicates that we will perform
583 // MSC after transportation.
584 fIsMultipleSacettring = true;
585 // Init the first-real-step falg: it will indicate if we do the first
586 // non-single scattering step in this volume with this particle
587 fIsFirstRealStep = false;
588 // If previously the partcile was on boundary it was within skin as
589 // well. When it is not within skin anymore it has just left the skin
590 // so we make the first real MSC step with the particle.
591 if (fIsWasOnBoundary && !fIsInsideSkin) {
592 // reset the 'was on boundary' indicator flag
593 fIsWasOnBoundary = false;
594 fIsFirstRealStep = true;
595 }
596 // If this is the first-real msc step (the partcile has just left the
597 // skin) or this is the first step with the particle (was born or
598 // primary):
599 // - set the initial range that will be used later to limit its step
600 // (only in this volume, because after boundary crossing at the
601 // first-real MSC step we will reset)
602 // - don't let the partcile to cross the volume just in one step
603 if (firstStep || fIsFirstRealStep || rangeinit>1.e+20) {
604 rangeinit = currentRange;
605 // If geomlimit < geombig than the particle might reach the boundary
606 // along its initial direction before losing its energy (in this step)
607 // Otherwise we can be sure that the particle will lose it energy
608 // before reaching the boundary along a starigth line so there is no
609 // geometrical limit appalied. [However, tgeom is set only in the
610 // first or the first-real MSC step. After the first or first real
611 // MSC step the direction will change tgeom won't guaranty anything!
612 // But we will try to end up within skindepth from the boundary using
613 // the actual value of geomlimit(See later at step reduction close to
614 // boundary).]
615 if (geomlimit<geombig) {
616 // transfrom straight line distance to the boundary to real step
617 // length based on the mean values (using the prestep point
618 // first-transport mean free path i.e. no energy loss correction)
619 if ((1.-geomlimit/fLambda1)> 0.) {
620 geomlimit = -fLambda1*G4Log(1.-geomlimit/fLambda1);
621 }
622 // the 2-different case that could lead us here
623 if (firstStep) {
624 tgeom = 2.*geomlimit/facgeom;
625 } else {
626 tgeom = geomlimit/facgeom;
627 }
628 } else {
629 tgeom = geombig;
630 }
631 }
632 // True step length limit from range factor. Noteice, that the initial
633 // range is used that was set at the first step or first-real MSC step
634 // in this volume with this particle.
635 tlimit = facrange*rangeinit;
636 // Take the minimum of the true step length limits coming from
637 // geometrical constraint or range-factor limitation
638 tlimit = std::min(tlimit,tgeom);
639 // Step reduction close to boundary: we try to end up within skindepth
640 // from the boundary ( Notice: in case of mag. field it might not work
641 // because geomlimit is the straigth line distance to the boundary in
642 // the currect direction (if geomlimit<geombig) and mag. field can
643 // change the initial direction. So te particle might hit some boundary
644 // before in a different direction. However, here we restrict the true
645 // path length to this (straight line) lenght so the corresponding
646 // transport distance (straight line) will be even shorter than
647 // geomlimit-0.999*skindepth after the change of true->geom.
648 if (geomlimit<geombig) {
649 tlimit = std::min(tlimit, geomlimit-0.999*skindepth);
650 }
651 // randomize 1st step or 1st 'normal' step in volume
652 if (firstStep || fIsFirstRealStep) {
653 fTheTrueStepLenght = std::min(fTheTrueStepLenght, Randomizetlimit());
654 } else {
655 fTheTrueStepLenght = std::min(fTheTrueStepLenght, tlimit);
656 }
657 }
660 geomlimit = presafety;
661 // Set skin depth = skin x elastic_mean_free_path
662 skindepth = skin*fLambda0;
663 // Check if we can try Single Scattering because we are within skindepth
664 // distance from/to a boundary OR the current minimum true-step-length is
665 // shorter than skindepth. NOTICE: the latest has only efficieny reasons
666 // because the MSC angular sampling is fine for any short steps but much
667 // faster to try single scattering in case of short steps.
669 //Try single scattering:
670 // - sample distance to next single scattering interaction (sslimit)
671 // - compare to current minimum length
672 // == if sslimit is the shorter:
673 // - set the step length to sslimit
674 // - indicate that single scattering needs to be done
675 // == else : nothing to do
676 //- in both cases, the step length was very short so geometrical and
677 // true path length are the same
679 // compare to current minimum step length
680 if (sslimit<fTheTrueStepLenght) {
681 fTheTrueStepLenght = sslimit;
682 fIsSingleScattering = true;
683 }
684 // short step -> true step length equal to geometrical path length
685 fTheZPathLenght = fTheTrueStepLenght;
686 // Set taht everything is done in step-limit phase so no MSC call
687 // We will check if we need to perform the single-scattering angular
688 // sampling i.e. if single elastic scattering was the winer!
689 fIsEverythingWasDone = true;
690 } else {
691 // After checking we know that we cannot try single scattering so we will
692 // need to make an MSC step
693 // Indicate that we need to make and MSC step.
694 fIsMultipleSacettring = true;
695 fIsEverythingWasDone = true;
696 // limit from range factor
697 fTheTrueStepLenght = std::min(fTheTrueStepLenght, facrange*currentRange);
698 // never let the particle go further than the safety if we are out of the skin
699 // if we are here we are out of the skin, presafety > 0.
700 if (fTheTrueStepLenght>presafety) {
701 fTheTrueStepLenght = std::min(fTheTrueStepLenght, presafety);
702 }
703 // make sure that we are still within the aplicability of condensed histry model
704 // i.e. true step length is not longer than first transport mean free path.
705 // We schould take into account energy loss along 0.5x lambda_transport1
706 // step length as well. So let it 0.5 x lambda_transport1
707 fTheTrueStepLenght = std::min(fTheTrueStepLenght, fLambda1*0.5);
708 }
709 } else {
710 // This is the default stepping algorithm: the fastest but the least
711 // accurate that corresponds to fUseSafety in Urban model. Note, that GS
712 // model can handle any short steps so we do not need the minimum limits
713 //
714 // NO single scattering in case of skin or short steps (by defult the MSC
715 // model will be single or even no scattering in case of short steps
716 // compared to the elastic mean free path.)
717 //
718 // indicate that MSC needs to be done (always and always after transportation)
719 fIsMultipleSacettring = true;
722 }
723 // Far from boundary-> in optimized mode do not sample dispalcement.
724 if ((distance<presafety) && (gIsOptimizationOn)) {
725 fIsNoDisplace = true;
726 } else {
727 // Urban like
729 rangeinit = currentRange;
730 fr = facrange;
731// We don't use this: we won't converge to the single scattering results with
732// decreasing range-factor.
733// rangeinit = std::max(rangeinit, fLambda1);
734// if(fLambda1 > lambdalimit) {
735// fr *= (0.75+0.25*fLambda1/lambdalimit);
736// }
737
738 }
739 //step limit
740 tlimit = std::max(fr*rangeinit, facsafety*presafety);
741 // first step randomization
743 fTheTrueStepLenght = std::min(fTheTrueStepLenght, Randomizetlimit());
744 } else {
745 fTheTrueStepLenght = std::min(fTheTrueStepLenght, tlimit);
746 }
747 }
748 }
749 //
750 // unset first-step
751 firstStep =false;
752 // performe single scattering, multiple scattering if this later can be done safely here
753 if (fIsEverythingWasDone) {
754 if (fIsSingleScattering) {
755 // sample single scattering
756 //G4double ekin = 0.5*(currentKinEnergy + GetEnergy(particle,currentRange-fTheTrueStepLenght,currentCouple));
758 G4double pt2 = currentKinEnergy*(currentKinEnergy+2.0*CLHEP::electron_mass_c2);
759 G4double beta2 = pt2/(pt2+CLHEP::electron_mass_c2*CLHEP::electron_mass_c2);
761 // protection
762 if (cost<-1.) cost = -1.;
763 if (cost> 1.) cost = 1.;
764 // compute sint
765 G4double dum = 1.-cost;
766 G4double sint = std::sqrt(dum*(2.-dum));
768 G4double sinPhi = std::sin(phi);
769 G4double cosPhi = std::cos(phi);
770 fTheNewDirection.set(sint*cosPhi,sint*sinPhi,cost);
771 } else if (fIsMultipleSacettring) {
772 // sample multiple scattering
774 } // and if single scattering but it was longer => nothing to do
775 } //else { do nothing here but after transportation
776 //
778}
Definition: G4DynamicParticle.hh:65
G4double GetLogKineticEnergy() const
G4double GetKineticEnergy() const
void SampleMSC()
Definition: G4GoudsmitSaundersonMscModel.cc:923
G4double GetTransportMeanFreePath(const G4ParticleDefinition *, G4double)
Definition: G4GoudsmitSaundersonMscModel.cc:365
G4double SingleScattering(G4double lambdaval, G4double scra, G4double lekin, G4double beta2, G4int matindx)
Definition: G4GoudsmitSaundersonTable.cc:514
const G4Material * GetMaterial() const
Definition: G4MaterialCutsCouple.hh:166
Definition: G4StepPoint.hh:56
G4StepPoint * GetPreStepPoint() const
const G4DynamicParticle * GetDynamicParticle() const
const G4MaterialCutsCouple * GetMaterialCutsCouple() const
const G4Step * GetStep() const
void SetCurrentCouple(const G4MaterialCutsCouple *)
Definition: G4VEmModel.hh:465
G4double ComputeGeomLimit(const G4Track &, G4double &presafety, G4double limit)
Definition: G4VMscModel.hh:287
G4double GetRange(const G4ParticleDefinition *part, G4double kineticEnergy, const G4MaterialCutsCouple *couple)
Definition: G4VMscModel.hh:330
G4double ConvertTrueToGeom(G4double &tLength, G4double &gLength)
Definition: G4VMscModel.hh:277
G4double ComputeSafety(const G4ThreeVector &position, G4double limit=DBL_MAX)
Definition: G4VMscModel.hh:269
◆ ComputeTrueStepLength()
Implements G4VMscModel.
Definition at line 833 of file G4GoudsmitSaundersonMscModel.cc.
833 {
834 // init
835 fIsEndedUpOnBoundary = false;
836 // step defined other than transportation
837 if (geomStepLength==fTheZPathLenght) {
838 return fTheTrueStepLenght;
839 }
840 // else ::
841 // - set the flag that transportation was the winer so DoNothin in DOIT !!
842 // - convert geom -> true by using the mean value
843 fIsEndedUpOnBoundary = true; // OR LAST STEP
844 fTheZPathLenght = geomStepLength;
845 // was a short single scattering step
846 if (fIsEverythingWasDone && !fIsMultipleSacettring) {
847 fTheTrueStepLenght = geomStepLength;
848 return fTheTrueStepLenght;
849 }
850 // t = z for very small step
851 if (geomStepLength<tlimitminfix2) {
852 fTheTrueStepLenght = geomStepLength;
853 // recalculation
854 } else {
855 G4double tlength = geomStepLength;
856 if (geomStepLength>fLambda1*tausmall) {
857 if (par1< 0.) {
858 tlength = -fLambda1*G4Log(1.-geomStepLength/fLambda1) ;
859 } else {
860 if (par1*par3*geomStepLength<1.) {
862 tlength = (1.-g4calc->powA( 1.-par1*par3*geomStepLength,1./par3))/par1;
863 } else {
864 tlength = currentRange;
865 }
866 }
867 if (tlength<geomStepLength || tlength>fTheTrueStepLenght) {
868 tlength = geomStepLength;
869 }
870 }
871 fTheTrueStepLenght = tlength;
872 }
873 //
874 return fTheTrueStepLenght;
875}
◆ CrossSectionPerVolume()
|
virtual |
Reimplemented from G4VEmModel.
Definition at line 309 of file G4GoudsmitSaundersonMscModel.cc.
313 {
315 //
316 fLambda0 = 0.0; // elastic mean free path
317 fLambda1 = 0.0; // first transport mean free path
318 fScrA = 0.0; // screening parameter
319 fG1 = 0.0; // first transport coef.
320 // use Moliere's screening (with Mott-corretion if it was requested)
321 G4double efEnergy = std::max(kineticEnergy, 10.*CLHEP::eV);
322 // total mometum square
323 G4double pt2 = efEnergy*(efEnergy+2.0*electron_mass_c2);
324 // beta square
325 G4double beta2 = pt2/(pt2+electron_mass_c2*electron_mass_c2);
326 // current material index
328 // Moliere's b_c
330 // get the Mott-correcton factors if Mott-correcton was requested by the user
331 fMCtoScrA = 1.0;
332 fMCtoQ1 = 1.0;
333 fMCtoG2PerG1 = 1.0;
334 G4double scpCor = 1.0;
335 if (fIsUseMottCorrection) {
336 fGSTable->GetMottCorrectionFactors(G4Log(efEnergy), beta2, matindx, fMCtoScrA, fMCtoQ1, fMCtoG2PerG1);
337 // ! no scattering power correction since the current couple is not set before this interface method is called
338 // scpCor = fGSTable->ComputeScatteringPowerCorrection(currentCouple, efEnergy);
339 } else if (fIsUsePWACorrection) {
340 fPWACorrection->GetPWACorrectionFactors(G4Log(efEnergy), beta2, matindx, fMCtoScrA, fMCtoQ1, fMCtoG2PerG1);
341 // scpCor = fGSTable->ComputeScatteringPowerCorrection(currentCouple, efEnergy);
342 }
343 // screening parameter:
344 // - if Mott-corretioncorrection: the Screened-Rutherford times Mott-corretion DCS with this
345 // screening parameter gives back the (elsepa) PWA first transport cross section
346 // - if PWA correction: he Screened-Rutherford DCS with this screening parameter
347 // gives back the (elsepa) PWA first transport cross section
348 fScrA = fGSTable->GetMoliereXc2(matindx)/(4.0*pt2*bc)*fMCtoScrA;
349 // elastic mean free path in Geant4 internal lenght units: the neglected (1+screening parameter) term is corrected
350 // (if Mott-corretion: the corrected screening parameter is used for this (1+A) correction + Moliere b_c is also
351 // corrected with the screening parameter correction)
352 fLambda0 = beta2*(1.+fScrA)*fMCtoScrA/bc/scpCor;
353 // first transport coefficient (if Mott-corretion: the corrected screening parameter is used (it will be fully
354 // consistent with the one used during the pre-computation of the Mott-correted GS angular distributions))
355 fG1 = 2.0*fScrA*((1.0+fScrA)*G4Log(1.0/fScrA+1.0)-1.0);
356 // first transport mean free path
357 fLambda1 = fLambda0/fG1;
358 xsecTr1 = 1./fLambda1;
359 return xsecTr1;
360}
void GetPWACorrectionFactors(G4double logekin, G4double beta2, G4int matindx, G4double &corToScr, G4double &corToQ1, G4double &corToG2PerG1)
Definition: G4GSPWACorrections.cc:81
void GetMottCorrectionFactors(G4double logekin, G4double beta2, G4int matindx, G4double &mcToScr, G4double &mcToQ1, G4double &mcToG2PerG1)
Definition: G4GoudsmitSaundersonTable.cc:543
G4double GetMoliereBc(G4int matindx)
Definition: G4GoudsmitSaundersonTable.hh:122
G4double GetMoliereXc2(G4int matindx)
Definition: G4GoudsmitSaundersonTable.hh:124
◆ GetGSTable()
|
inline |
Definition at line 178 of file G4GoudsmitSaundersonMscModel.hh.
178{ return fGSTable; }
Referenced by InitialiseLocal().
◆ GetOptionMottCorrection()
|
inline |
Definition at line 176 of file G4GoudsmitSaundersonMscModel.hh.
176{ return fIsUseMottCorrection; }
Referenced by InitialiseLocal().
◆ GetOptionPWACorrection()
|
inline |
Definition at line 172 of file G4GoudsmitSaundersonMscModel.hh.
172{ return fIsUsePWACorrection; }
Referenced by InitialiseLocal().
◆ GetPWACorrection()
|
inline |
Definition at line 180 of file G4GoudsmitSaundersonMscModel.hh.
180{ return fPWACorrection; }
Referenced by InitialiseLocal().
◆ GetTransportMeanFreePath()
| G4double G4GoudsmitSaundersonMscModel::GetTransportMeanFreePath | ( | const G4ParticleDefinition * | , |
| G4double | kineticEnergy | ||
| ) |
Definition at line 365 of file G4GoudsmitSaundersonMscModel.cc.
366 {
367 // kinetic energy is assumed to be in Geant4 internal energy unit which is MeV
368 G4double efEnergy = kineticEnergy;
369 //
371 //
372 fLambda0 = 0.0; // elastic mean free path
373 fLambda1 = 0.0; // first transport mean free path
374 fScrA = 0.0; // screening parameter
375 fG1 = 0.0; // first transport coef.
376
377 // use Moliere's screening (with Mott-corretion if it was requested)
378 if (efEnergy<10.*CLHEP::eV) efEnergy = 10.*CLHEP::eV;
379 // total mometum square
380 G4double pt2 = efEnergy*(efEnergy+2.0*electron_mass_c2);
381 // beta square
382 G4double beta2 = pt2/(pt2+electron_mass_c2*electron_mass_c2);
383 // current material index
385 // Moliere's b_c
387 // get the Mott-correcton factors if Mott-correcton was requested by the user
388 fMCtoScrA = 1.0;
389 fMCtoQ1 = 1.0;
390 fMCtoG2PerG1 = 1.0;
391 G4double scpCor = 1.0;
392 if (fIsUseMottCorrection) {
393 fGSTable->GetMottCorrectionFactors(G4Log(efEnergy), beta2, matindx, fMCtoScrA, fMCtoQ1, fMCtoG2PerG1);
394 scpCor = fGSTable->ComputeScatteringPowerCorrection(currentCouple, efEnergy);
395 } else if (fIsUsePWACorrection) {
396 fPWACorrection->GetPWACorrectionFactors(G4Log(efEnergy), beta2, matindx, fMCtoScrA, fMCtoQ1, fMCtoG2PerG1);
397 // scpCor = fGSTable->ComputeScatteringPowerCorrection(currentCouple, efEnergy);
398 }
399 // screening parameter:
400 // - if Mott-corretioncorrection: the Screened-Rutherford times Mott-corretion DCS with this
401 // screening parameter gives back the (elsepa) PWA first transport cross section
402 // - if PWA correction: he Screened-Rutherford DCS with this screening parameter
403 // gives back the (elsepa) PWA first transport cross section
404 fScrA = fGSTable->GetMoliereXc2(matindx)/(4.0*pt2*bc)*fMCtoScrA;
405 // elastic mean free path in Geant4 internal lenght units: the neglected (1+screening parameter) term is corrected
406 // (if Mott-corretion: the corrected screening parameter is used for this (1+A) correction + Moliere b_c is also
407 // corrected with the screening parameter correction)
408 fLambda0 = beta2*(1.+fScrA)*fMCtoScrA/bc/scpCor;
409 // first transport coefficient (if Mott-corretion: the corrected screening parameter is used (it will be fully
410 // consistent with the one used during the pre-computation of the Mott-correted GS angular distributions))
411 fG1 = 2.0*fScrA*((1.0+fScrA)*G4Log(1.0/fScrA+1.0)-1.0);
412 // first transport mean free path
413 fLambda1 = fLambda0/fG1;
414
415 return fLambda1;
416}
G4double ComputeScatteringPowerCorrection(const G4MaterialCutsCouple *matcut, G4double ekin)
Definition: G4GoudsmitSaundersonTable.cc:611
Definition: G4Material.hh:118
Referenced by ComputeTruePathLengthLimit(), and SampleMSC().
◆ Initialise()
|
virtual |
Implements G4VEmModel.
Definition at line 251 of file G4GoudsmitSaundersonMscModel.cc.
251 {
252 SetParticle(p);
253 InitialiseParameters(p);
254 // -create GoudsmitSaundersonTable and init its Mott-correction member if
255 // Mott-correction was required
257 // get the Mott-correction flag from EmParameters
259 fIsUseMottCorrection = true;
260 }
261 // Mott-correction includes other way of PWA x-section corrections so deactivate it even if it was true
262 // when Mott-correction is activated by the user
263 if (fIsUseMottCorrection) {
264 fIsUsePWACorrection = false;
265 }
266 // clear GS-table
267 if (fGSTable) {
268 delete fGSTable;
269 fGSTable = nullptr;
270 }
271 // clear PWA corrections table if any
272 if (fPWACorrection) {
273 delete fPWACorrection;
274 fPWACorrection = nullptr;
275 }
276 // create GS-table
280 }
282 // G4GSTable will be initialised:
283 // - Screened-Rutherford DCS based GS angular distributions will be loaded only if they are not there yet
284 // - Mott-correction will be initialised if Mott-correction was requested to be used
285 fGSTable->SetOptionMottCorrection(fIsUseMottCorrection);
286 // - set PWA correction (correction to integrated quantites from Dirac-PWA)
287 fGSTable->SetOptionPWACorrection(fIsUsePWACorrection);
288 // init
290 // create PWA corrections table if it was requested (and not disactivated because active Mott-correction)
291 if (fIsUsePWACorrection) {
293 fPWACorrection->Initialise();
294 }
295 }
296 fParticleChange = GetParticleChangeForMSC(p);
297}
Definition: G4GSPWACorrections.hh:61
void SetOptionPWACorrection(G4bool val)
Definition: G4GoudsmitSaundersonTable.hh:133
void Initialise(G4double lownergylimit, G4double highenergylimit)
Definition: G4GoudsmitSaundersonTable.cc:166
void SetOptionMottCorrection(G4bool val)
Definition: G4GoudsmitSaundersonTable.hh:131
G4double GetPDGCharge() const
Definition: G4ParticleDefinition.hh:112
G4ParticleChangeForMSC * GetParticleChangeForMSC(const G4ParticleDefinition *p=nullptr)
Definition: G4VMscModel.cc:91
void InitialiseParameters(const G4ParticleDefinition *)
Definition: G4VMscModel.cc:139
◆ InitialiseLocal()
|
virtual |
Reimplemented from G4VEmModel.
Definition at line 300 of file G4GoudsmitSaundersonMscModel.cc.
300 {
302 fIsUseMottCorrection = static_cast<G4GoudsmitSaundersonMscModel*>(masterModel)->GetOptionMottCorrection();
303 fIsUsePWACorrection = static_cast<G4GoudsmitSaundersonMscModel*>(masterModel)->GetOptionPWACorrection();
305}
G4GSPWACorrections * GetPWACorrection()
Definition: G4GoudsmitSaundersonMscModel.hh:180
G4GoudsmitSaundersonTable * GetGSTable()
Definition: G4GoudsmitSaundersonMscModel.hh:178
G4bool GetOptionMottCorrection() const
Definition: G4GoudsmitSaundersonMscModel.hh:176
G4bool GetOptionPWACorrection() const
Definition: G4GoudsmitSaundersonMscModel.hh:172
◆ SampleMSC()
| void G4GoudsmitSaundersonMscModel::SampleMSC | ( | ) |
Definition at line 923 of file G4GoudsmitSaundersonMscModel.cc.
923 {
924 fIsNoScatteringInMSC = false;
925 // kinetic energy is assumed to be in Geant4 internal energy unit which is MeV
926 G4double kineticEnergy = currentKinEnergy;
927 //
928 // Energy loss correction: 2 version
929 G4double eloss = 0.0;
930// if (fTheTrueStepLenght > currentRange*dtrl) {
931 eloss = kineticEnergy - GetEnergy(particle,currentRange-fTheTrueStepLenght,currentCouple);
932// } else {
933// eloss = fTheTrueStepLenght*GetDEDX(particle,kineticEnergy,currentCouple);
934// }
935
936 G4double tau = 0.;// = kineticEnergy/electron_mass_c2; // where kinEnergy is the mean kinetic energy
940
941 // - init.
942 G4double efEnergy = kineticEnergy;
943 G4double efStep = fTheTrueStepLenght;
944
945 G4double kineticEnergy0 = kineticEnergy;
946 if (gIsUseAccurate) { // - use accurate energy loss correction
947 kineticEnergy -= 0.5*eloss; // mean energy along the full step
948 // other parameters for energy loss corrections
949 tau = kineticEnergy/electron_mass_c2; // where kinEnergy is the mean kinetic energy
950 tau2 = tau*tau;
951 eps0 = eloss/kineticEnergy0; // energy loss fraction to the begin step energy
952 epsm = eloss/kineticEnergy; // energy loss fraction to the mean step energy
953
954 efEnergy = kineticEnergy * (1.-epsm*epsm*(6.+10.*tau+5.*tau2)/(24.*tau2+48.*tau+72.));
955 G4double dum = 0.166666*(4.+tau*(6.+tau*(7.+tau*(4.+tau))))*(epsm/((tau+1.)*(tau+2.)))*(epsm/((tau+1.)*(tau+2.)));
956 efStep = fTheTrueStepLenght*(1.-dum);
957 } else { // - take only mean energy
958 kineticEnergy -= 0.5*eloss; // mean energy along the full step
959 efEnergy = kineticEnergy;
961 eps0 = eloss/kineticEnergy0;
962 epsm = eps0/(1.-0.5*eps0);
963 G4double temp = 0.3*(1 -factor*(1.-0.333333*factor))*eps0*eps0;
964 efStep = fTheTrueStepLenght*(1.+temp);
965 }
966 //
967 // compute elastic mfp, first transport mfp, screening parameter, and G1 (with Mott-correction
968 // if it was requested by the user)
969 fLambda1 = GetTransportMeanFreePath(particle, efEnergy);
970 // s/lambda_el
971 G4double lambdan=0.;
972 if (fLambda0>0.0) {
973 lambdan=efStep/fLambda0;
974 }
975 if (lambdan<=1.0e-12) {
976 if (fIsEverythingWasDone) {
977 fTheZPathLenght = fTheTrueStepLenght;
978 }
979 fIsNoScatteringInMSC = true;
980 return;
981 }
982 // first moment: 2.* lambdan *scrA*((1.+scrA)*log(1.+1./scrA)-1.);
983 G4double Qn1 = lambdan *fG1;
984 // sample scattering angles
985 // new direction, relative to the orriginal one is in {uss,vss,wss}
986 G4double cosTheta1 = 1.0, sinTheta1 = 0.0, cosTheta2 = 1.0, sinTheta2 = 0.0;
987 G4double cosPhi1 = 1.0, sinPhi1 = 0.0, cosPhi2 = 1.0, sinPhi2 = 0.0;
988 G4double uss = 0.0, vss = 0.0, wss = 1.0;
989 G4double x_coord = 0.0, y_coord = 0.0, z_coord = 1.0;
990 G4double u2 = 0.0, v2 = 0.0;
991 // if we are above the upper grid limit with lambdaxG1=true-length/first-trans-mfp
992 // => izotropic distribution: lambG1_max =7.992 but set it to 7
993 if (0.5*Qn1 > 7.0){
994 cosTheta1 = 1.-2.*G4UniformRand();
995 sinTheta1 = std::sqrt((1.-cosTheta1)*(1.+cosTheta1));
996 cosTheta2 = 1.-2.*G4UniformRand();
997 sinTheta2 = std::sqrt((1.-cosTheta2)*(1.+cosTheta2));
998 } else {
999 // sample 2 scattering cost1, sint1, cost2 and sint2 for half path
1001 G4double pt2 = efEnergy*(efEnergy+2.0*CLHEP::electron_mass_c2);
1002 G4double beta2 = pt2/(pt2+CLHEP::electron_mass_c2*CLHEP::electron_mass_c2);
1003 // backup GS angular dtr pointer (kinetic energy and delta index in case of Mott-correction)
1004 // if the first was an msc sampling (the same will be used if the second is also an msc step)
1006 G4int mcEkinIdx = -1;
1007 G4int mcDeltIdx = -1;
1008 G4double transfPar = 0.;
1009 G4bool isMsc = fGSTable->Sampling(0.5*lambdan, 0.5*Qn1, fScrA, cosTheta1, sinTheta1, lekin, beta2,
1010 currentMaterialIndex, &gsDtr, mcEkinIdx, mcDeltIdx, transfPar,
1011 true);
1012 fGSTable->Sampling(0.5*lambdan, 0.5*Qn1, fScrA, cosTheta2, sinTheta2, lekin, beta2,
1013 currentMaterialIndex, &gsDtr, mcEkinIdx, mcDeltIdx, transfPar, !isMsc);
1014 if (cosTheta1+cosTheta2==2.) { // no scattering happened
1015 if (fIsEverythingWasDone)
1016 fTheZPathLenght = fTheTrueStepLenght;
1017 fIsNoScatteringInMSC = true;
1018 return;
1019 }
1020 }
1021 // sample 2 azimuthal angles
1023 sinPhi1 = std::sin(phi1);
1024 cosPhi1 = std::cos(phi1);
1026 sinPhi2 = std::sin(phi2);
1027 cosPhi2 = std::cos(phi2);
1028
1029 // compute final direction realtive to z-dir
1030 u2 = sinTheta2*cosPhi2;
1031 v2 = sinTheta2*sinPhi2;
1032 G4double u2p = cosTheta1*u2 + sinTheta1*cosTheta2;
1033 uss = u2p*cosPhi1 - v2*sinPhi1;
1034 vss = u2p*sinPhi1 + v2*cosPhi1;
1035 wss = cosTheta1*cosTheta2 - sinTheta1*u2;
1036
1037 // set new direction (is scattering frame)
1038 fTheNewDirection.set(uss,vss,wss);
1039
1040 // set the fTheZPathLenght if we don't sample displacement and
1041 // we should do everything at the step-limit-phase before we return
1042 if(fIsNoDisplace && fIsEverythingWasDone)
1043 fTheZPathLenght = fTheTrueStepLenght;
1044
1045 // in optimized-mode if the current-safety > current-range we do not use dispalcement
1046 if(fIsNoDisplace)
1047 return;
1048
1049 //////////////////////////////////////////////////////////////////////
1050 // Compute final position
1051 Qn1 *= fMCtoQ1;
1052 if (gIsUseAccurate) {
1053 // correction parameter
1054 G4double par =1.;
1055 if(Qn1<0.7) par = 1.;
1056 else if (Qn1<7.0) par = -0.031376*Qn1+1.01356;
1057 else par = 0.79;
1058
1059 // Moments with energy loss correction
1060 // --first the uncorrected (for energy loss) values of gamma, eta, a1=a2=0.5*(1-eta), delta
1061 // gamma = G_2/G_1 based on G2 computed from A by using the Wentzel DCS form of G2
1063 G4double gamma = 6.0*fScrA*(1.0 + fScrA)*(loga*(1.0 + 2.0*fScrA) - 2.0)/fG1;
1064 gamma *= fMCtoG2PerG1;
1065 // sample eta from p(eta)=2*eta i.e. P(eta) = eta_square ;-> P(eta) = rand --> eta = sqrt(rand)
1068 // 0.5 +sqrt(6)/6 = 0.9082483;
1069 // 1/(4*sqrt(6)) = 0.1020621;
1070 // (4-sqrt(6)/(24*sqrt(6))) = 0.026374715
1071 // delta = 0.9082483-(0.1020621-0.0263747*gamma)*Qn1 without energy loss cor.
1072 G4double delta = 0.9082483-(0.1020621-0.0263747*gamma)*Qn1;
1073
1074 // compute alpha1 and alpha2 for energy loss correction
1075 G4double temp1 = 2.0 + tau;
1076 G4double temp = (2.0+tau*temp1)/((tau+1.0)*temp1);
1077 //Take logarithmic dependence
1078 temp = temp - (tau+1.0)/((tau+2.0)*(loga*(1.0+fScrA)-1.0));
1079 temp = temp * epsm;
1080 temp1 = 1.0 - temp;
1081 delta = delta + 0.40824829*(eps0*(tau+1.0)/((tau+2.0)*
1082 (loga*(1.0+fScrA)-1.0)*(loga*(1.0+2.0*fScrA)-2.0)) - 0.25*temp*temp);
1083 G4double b = eta*delta;
1084 G4double c = eta*(1.0-delta);
1085
1086 //Calculate transport direction cosines:
1087 // ut,vt,wt is the final position divided by the true step length
1088 G4double w1v2 = cosTheta1*v2;
1089 G4double ut = b*sinTheta1*cosPhi1 + c*(cosPhi1*u2 - sinPhi1*w1v2) + eta1*uss*temp1;
1090 G4double vt = b*sinTheta1*sinPhi1 + c*(sinPhi1*u2 + cosPhi1*w1v2) + eta1*vss*temp1;
1091 G4double wt = eta1*(1+temp) + b*cosTheta1 + c*cosTheta2 + eta1*wss*temp1;
1092
1093 // long step correction
1094 ut *=par;
1095 vt *=par;
1096 wt *=par;
1097
1098 // final position relative to the pre-step point in the scattering frame
1099 // ut = x_f/s so needs to multiply by s
1100 x_coord = ut*fTheTrueStepLenght;
1101 y_coord = vt*fTheTrueStepLenght;
1102 z_coord = wt*fTheTrueStepLenght;
1103
1104 if(fIsEverythingWasDone){
1105 // We sample in the step limit so set fTheZPathLenght = transportDistance
1106 // and lateral displacement (x_coord,y_coord,z_coord-transportDistance)
1107 //Calculate transport distance
1108 G4double transportDistance = std::sqrt(x_coord*x_coord+y_coord*y_coord+z_coord*z_coord);
1109 // protection
1110 if(transportDistance>fTheTrueStepLenght)
1111 transportDistance = fTheTrueStepLenght;
1112 fTheZPathLenght = transportDistance;
1113 }
1114 // else:: we sample in the DoIt so
1115 // the fTheZPathLenght was already set and was taken as transport along zet
1116 fTheDisplacementVector.set(x_coord,y_coord,z_coord-fTheZPathLenght);
1117 } else {
1118 // compute zz = <z>/tPathLength
1119 // s -> true-path-length
1120 // z -> geom-path-length:: when PRESTA is used z =(def.) <z>
1121 // r -> lateral displacement = s/2 sin(theta) => x_f = r cos(phi); y_f = r sin(phi)
1122 G4double zz = 0.0;
1123 if(fIsEverythingWasDone){
1124 // We sample in the step limit so set fTheZPathLenght = transportDistance
1125 // and lateral displacement (x_coord,y_coord,z_coord-transportDistance)
1126 if(Qn1<0.1) { // use 3-order Taylor approximation of (1-exp(-x))/x around x=0
1127 zz = 1.0 - Qn1*(0.5 - Qn1*(0.166666667 - 0.041666667*Qn1)); // 1/6 =0.166..7 ; 1/24=0.041..
1128 } else {
1129 zz = (1.-G4Exp(-Qn1))/Qn1;
1130 }
1131 } else {
1132 // we sample in the DoIt so
1133 // the fTheZPathLenght was already set and was taken as transport along zet
1134 zz = fTheZPathLenght/fTheTrueStepLenght;
1135 }
1136
1138 if(rr >= 0.25) rr = 0.25; // (1-<z>^2/s^2)/sin^2(theta) >= r^2/(s^2 sin^2(theta)) = 1/4 must hold
1140 x_coord = rperp*uss;
1141 y_coord = rperp*vss;
1142 z_coord = zz*fTheTrueStepLenght;
1143
1144 if(fIsEverythingWasDone){
1145 G4double transportDistance = std::sqrt(x_coord*x_coord + y_coord*y_coord + z_coord*z_coord);
1146 fTheZPathLenght = transportDistance;
1147 }
1148
1149 fTheDisplacementVector.set(x_coord,y_coord,z_coord- fTheZPathLenght);
1150 }
1151}
G4bool Sampling(G4double lambdaval, G4double qval, G4double scra, G4double &cost, G4double &sint, G4double lekin, G4double beta2, G4int matindx, GSMSCAngularDtr **gsDtr, G4int &mcekini, G4int &mcdelti, G4double &transfPar, G4bool isfirst)
Definition: G4GoudsmitSaundersonTable.cc:212
Referenced by ComputeTruePathLengthLimit(), and SampleScattering().
◆ SampleScattering()
|
virtual |
Implements G4VMscModel.
Definition at line 878 of file G4GoudsmitSaundersonMscModel.cc.
878 {
880 // single scattering was and scattering happend
881 fTheNewDirection.rotateUz(oldDirection);
882 fParticleChange->ProposeMomentumDirection(fTheNewDirection);
883 return fTheDisplacementVector;
885 if (fIsEndedUpOnBoundary) { // do nothing on the boundary
886 return fTheDisplacementVector;
887 } else if (fIsEverythingWasDone) { // evrything is done if not optimizations case !!!
888 // check single scattering and see if it happened
889 if (fIsSingleScattering) {
890 fTheNewDirection.rotateUz(oldDirection);
891 fParticleChange->ProposeMomentumDirection(fTheNewDirection);
892 return fTheDisplacementVector;
893 }
894 // check if multiple scattering happened and do things only if scattering was really happening
895 if (fIsMultipleSacettring && !fIsNoScatteringInMSC) {
896 fTheNewDirection.rotateUz(oldDirection);
897 fTheDisplacementVector.rotateUz(oldDirection);
898 fParticleChange->ProposeMomentumDirection(fTheNewDirection);
899 }
900 // The only thing that could happen if we are here (fUseSafety and fIsEverythingWasDone)
901 // is that single scattering was tried but did not win so scattering did not happen.
902 // So no displacement and no scattering
903 return fTheDisplacementVector;
904 }
905 //
906 // The only thing that could still happen with fUseSafetyPlus is that we are in the
907 // optimization branch: so sample MSC angle here (no displacement)
908 }
909 //else MSC needs to be done here
910 SampleMSC();
911 if (!fIsNoScatteringInMSC) {
912 fTheNewDirection.rotateUz(oldDirection);
913 fParticleChange->ProposeMomentumDirection(fTheNewDirection);
914 if (!fIsNoDisplace) {
915 fTheDisplacementVector.rotateUz(oldDirection);
916 }
917 }
918 //
919 return fTheDisplacementVector;
920}
void ProposeMomentumDirection(const G4ThreeVector &Pfinal)
◆ SetOptionMottCorrection()
|
inline |
Definition at line 174 of file G4GoudsmitSaundersonMscModel.hh.
174{ fIsUseMottCorrection = opt; }
◆ SetOptionPWACorrection()
|
inline |
Definition at line 170 of file G4GoudsmitSaundersonMscModel.hh.
170{ fIsUsePWACorrection = opt; }
◆ StartTracking()
|
virtual |
Reimplemented from G4VEmModel.
Definition at line 461 of file G4GoudsmitSaundersonMscModel.cc.
461 {
463 firstStep = true;
464 tlimit = tgeom = rangeinit = geombig;
465 rangeinit = 1.e+21;
466}
G4ParticleDefinition * GetDefinition() const
The documentation for this class was generated from the following files:
