lars/geant4
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Import Geant4 8.2.0 source tree

Browse Source
This commit is contained in:
Gabriele Cosmo
2016-06-09 14:55:03 +02:00
parent 216a75eeb1
commit fe73f43734
6714 changed files with 118229 additions and 68144 deletions
Download Patch File Download Diff File Expand all files Collapse all files
source/processes/electromagnetic/standard/src/G4UrbanMscModel.cc
+266 -132
View File
@@ -23,8 +23,8 @@
// * acceptance of all terms of the Geant4 Software license. *
// ********************************************************************
//
// $Id: G4UrbanMscModel.cc,v 1.15 2006/06/29 19:53:34 gunter Exp $
// GEANT4 tag $Name: geant4-08-01 $
// $Id: G4UrbanMscModel.cc,v 1.26 2006/12/04 05:53:24 urban Exp $
// GEANT4 tag $Name: geant4-08-02 $
//
// -------------------------------------------------------------------
//
@@ -90,6 +90,30 @@
// c_highland 13.6*MeV ---> 13.26*MeV,
// corr_highland 0.555 ---> 0.54,
// value of data member geommin changed (5 nm -> 1 nm) (L.Urban)
// 13-10-06 data member factail removed, data member tkinlimit changed
// to lambdalimit,
// new data members tgeom,tnow,skin,skindepth,Zeff,geomlimit
// G4double GeomLimit(const G4Track& track) changed to
// void GeomLimit(const G4Track& track)
// - important changes in ComputeTruePathLengthLimit:
// possibility to have very small step(s) with single scattering
// before boundary crossing (with skin > 0)
// - changes in SampleCosineTheta :
// single scattering if step <= stepmin, parameter theta0
// slightly modified, tail modified (L.Urban)
// 20-10-06 parameter theta0 now computed in the (public)
// function ComputeTheta0,
// single scattering modified allowing not small
// angles as well (L.Urban)
// 23-10-06 correction in SampleSecondaries, now safety update
// computed in a simpler/faster way (L.Urban)
// 06-11-06 corrections in ComputeTruePathLengthLimit, results are
// more stable in calorimeters (L.Urban)
// 07-11-06 fix in GeomPathLength and SampleCosineTheta (L.Urban)
// 15-11-06 bugfix in SampleCosineTheta (L.Urban)
// 20-11-06 bugfix in single scattering part of SampleCosineTheta,
// single scattering just before boundary crossing now (L.Urban)
// 04-12-06 fix in ComputeTruePathLengthLimit (L.Urban)
//
// Class Description:
@@ -112,21 +136,23 @@
#include "G4TransportationManager.hh"
#include "G4Navigator.hh"
#include "G4Poisson.hh"
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
using namespace std;
G4UrbanMscModel::G4UrbanMscModel(G4double m_facrange, G4double m_dtrl,
G4double m_tkinlimit,
G4double m_facgeom, G4double m_factail,
G4double m_lambdalimit,
G4double m_facgeom,G4double m_skin,
G4bool m_samplez, G4bool m_stepAlg,
const G4String& nam)
: G4VEmModel(nam),
dtrl(m_dtrl),
factail(m_factail),
Tkinlimit(m_tkinlimit),
lambdalimit(m_lambdalimit),
facrange(m_facrange),
facgeom(m_facgeom),
skin(m_skin),
samplez(m_samplez),
steppingAlgorithm(m_stepAlg),
isInitialized(false)
@@ -136,26 +162,34 @@ G4UrbanMscModel::G4UrbanMscModel(G4double m_facrange, G4double m_dtrl,
taulim = 1.e-6;
currentTau = taulim;
stepmin = 1.e-6*mm;
skindepth = (skin-1)*stepmin;
skindepth1 = skindepth+stepmin;
currentRange = 0. ;
frscaling2 = 0.1;
frscaling2 = 0.25;
frscaling1 = 1.-frscaling2;
tlimit = 1.e10*mm;
tlimitmin = 5.e-6*mm;
tlimitminfix = 5.e-6*mm;
tlimitmin = 10.e-6*mm;
tlimitminfix = 10.e-6*mm;
tnow = 10.e-6*mm;
nstepmax = 25.;
tgeom = 1.e50*mm;
geombig = 1.e50*mm;
geommin = 1.e-6*mm;
presafety = 0.*mm;
facsafety = 0.20;
geommin = 1.e-3*mm;
geomlimit = geombig;
presafety = 0.*mm;
facsafety = 0.25;
Zeff = 1.;
particle = 0;
theManager = G4LossTableManager::Instance();
inside = false;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4UrbanMscModel::~G4UrbanMscModel()
{}
{
delete safetyHelper;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -173,6 +207,8 @@ void G4UrbanMscModel::Initialise(const G4ParticleDefinition* p,
navigator = G4TransportationManager::GetTransportationManager()
->GetNavigatorForTracking();
safetyHelper= new G4SafetyHelper();
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -416,7 +452,6 @@ G4double G4UrbanMscModel::ComputeCrossSectionPerAtom(
else if(AtomicNumber > Z2)
sigma = AtomicNumber*AtomicNumber*c2/(Z2*Z2);
}
// G4cout << "e= " << KineticEnergy << " sigma= " << sigma << G4endl;
return sigma;
}
@@ -437,10 +472,12 @@ G4double G4UrbanMscModel::ComputeTruePathLengthLimit(
currentKinEnergy = dp->GetKineticEnergy();
currentRange =
theManager->GetRangeFromRestricteDEDX(particle,currentKinEnergy,couple);
currentRadLength = couple->GetMaterial()->GetRadlen();
lambda0 = GetLambda(currentKinEnergy);
tPathLength = currentMinimalStep;
if(tPathLength > currentRange)
tPathLength = currentRange;
G4StepPoint* sp = track.GetStep()->GetPreStepPoint();
presafety = sp->GetSafety();
G4StepStatus stepStatus = sp->GetStepStatus();
@@ -450,59 +487,112 @@ G4double G4UrbanMscModel::ComputeTruePathLengthLimit(
//
if (steppingAlgorithm)
{
if((stepNumber > 1) && inside)
return tPathLength;
//compute geomlimit and presafety
GeomLimit(track);
if((stepStatus == fGeomBoundary) || (stepNumber == 1))
{
//define tlimitmin here (it depends on lambda!)
tlimitmin = lambda0/nstepmax;
if(tlimitmin < tlimitminfix) tlimitmin = tlimitminfix;
if((stepNumber == 1) && (currentRange < presafety))
{
stepmin = 1.e-6*mm;
inside = true;
return tPathLength;
}
else
inside = false;
// not so strong step restriction above Tlimit
// facrange scaling in lambda
// not so strong step restriction above llimit
G4double facr = facrange;
if(currentKinEnergy > Tlimit)
facr *= frscaling1+frscaling2*currentKinEnergy/Tlimit;
if(lambda0 > llimit)
facr *= frscaling1+frscaling2*lambda0/llimit;
// constraint from the physics
if (currentRange > lambda0) tlimit = facr*currentRange;
else tlimit = facr*lambda0;
// constraint from the geometry (if tlimit above is too big)
tgeom = geombig;
if(geomlimit > geommin)
{
if(stepStatus == fGeomBoundary)
tgeom = geomlimit/facgeom;
else
tgeom = 2.*geomlimit/facgeom;
}
//define stepmin here (it depends on lambda!)
//rough estimation of lambda_elastic/lambda_transport
G4double rat = currentKinEnergy/MeV ;
rat = 1.e-3/(rat*(10.+rat)) ;
//stepmin ~ lambda_elastic
stepmin = rat*lambda0;
skindepth = (skin-1.)*stepmin;
skindepth1 = skindepth+stepmin;
if(stepmin > tgeom) stepmin = tgeom;
//define tlimitmin
tlimitmin = lambda0/nstepmax;
if(tlimitmin < stepmin) tlimitmin = 1.01*stepmin;
if(tlimitmin < tlimitminfix) tlimitmin = tlimitminfix;
//lower limit for tlimit
if(tlimit < tlimitmin) tlimit = tlimitmin;
G4double geomlimit = GeomLimit(track);
// constraint from the geometry (if tlimit above is too big)
if(geomlimit > geommin)
{
if(stepStatus == fGeomBoundary)
{
if(tlimit > geomlimit/facgeom)
tlimit = geomlimit/facgeom;
}
else
{
if(tlimit > 2.*geomlimit/facgeom)
tlimit = 2.*geomlimit/facgeom;
}
}
}
if(stepNumber == 1)
{
// range <= presafety ---> particle is not able to leave volume
if(currentRange <= presafety)
return currentMinimalStep;
//check against geometry limit
if(tlimit > tgeom) tlimit = tgeom;
//if track starts far from boundaries increase tlimit!
if(tlimit < facsafety*presafety)
if(tlimit < facsafety*presafety)
tlimit = facsafety*presafety ;
}
// range <= presafety ---> particle is not able to leave volume
if(currentRange <= presafety)
return currentMinimalStep;
if(tPathLength > tlimit) tPathLength = tlimit;
// "randomize" tlimit
tlimit *= 0.5+G4UniformRand();
}
if(currentRange < presafety)
{
inside = true;
return tPathLength;
}
// shortcut
if((tPathLength < tlimit) &&
(tPathLength < presafety))
return tPathLength;
//if track far from boundaries increase tPathLength
tnow = tlimit;
if(tlimit < facsafety*presafety)
tnow = facsafety*presafety ;
// step reduction near to boundary
if(skindepth >= 0.)
{
if(geomlimit > skindepth)
{
if(tnow > geomlimit-skindepth)
tnow = geomlimit-skindepth;
}
else
{
if(tnow > stepmin)
tnow = stepmin;
}
}
if(tnow < stepmin)
tnow = stepmin;
if(tPathLength > tnow)
tPathLength = tnow ;
}
// version similar to 7.1 (needed for some experiments)
//
else
{
if(stepNumber == 1)
@@ -522,9 +612,9 @@ G4double G4UrbanMscModel::ComputeTruePathLengthLimit(
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4UrbanMscModel::GeomLimit(const G4Track& track)
void G4UrbanMscModel::GeomLimit(const G4Track& track)
{
G4double geomlimit = geombig;
geomlimit = geombig;
// no geomlimit for the World volume
if((track.GetVolume() != 0) &&
@@ -538,11 +628,7 @@ G4double G4UrbanMscModel::GeomLimit(const G4Track& track)
track.GetMomentumDirection(),
cstep,
presafety);
if(geomlimit < geommin) geomlimit = geommin;
}
return geomlimit;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -550,7 +636,6 @@ G4double G4UrbanMscModel::GeomLimit(const G4Track& track)
G4double G4UrbanMscModel::ComputeGeomPathLength(G4double)
{
// do the true -> geom transformation
const G4double ztmax = 0.99, onethird = 1./3. ;
lambdaeff = lambda0;
par1 = -1. ;
@@ -565,7 +650,7 @@ G4double G4UrbanMscModel::ComputeGeomPathLength(G4double)
G4double tau = tPathLength/lambda0 ;
if ((tau <= tausmall) || (tPathLength < stepmin)) {
if ((tau <= tausmall) || (tPathLength <= stepmin)) {
geomLength = tPathLength;
if(geomLength > lambda0) geomLength = lambda0;
return geomLength;
@@ -574,12 +659,15 @@ G4double G4UrbanMscModel::ComputeGeomPathLength(G4double)
G4double zmean = tPathLength;
if (tPathLength < currentRange*dtrl) {
zmean = lambda0*(1.-exp(-tau));
if(tau < taulim) zmean = tPathLength*(1.-0.5*tPathLength/lambda0) ;
if(tau < taulim) zmean = tPathLength*(1.-0.5*tau) ;
} else if(currentKinEnergy < mass) {
par1 = 1./currentRange ;
par2 = 1./(par1*lambda0) ;
par3 = 1.+par2 ;
zmean = (1.-exp(par3*log(1.-tPathLength/currentRange)))/(par1*par3) ;
if(tPathLength < currentRange)
zmean = (1.-exp(par3*log(1.-tPathLength/currentRange)))/(par1*par3) ;
else
zmean = 1./(par1*par3) ;
} else {
G4double T1 = theManager->GetEnergy(particle,currentRange-tPathLength,couple);
G4double lambda1 = GetLambda(T1);
@@ -590,32 +678,37 @@ G4double G4UrbanMscModel::ComputeGeomPathLength(G4double)
zmean = (1.-exp(par3*log(lambda1/lambda0)))/(par1*par3) ;
}
// sample z
zPathLength = zmean ;
G4double zt = zmean/tPathLength ;
if (samplez && tPathLength >= stepmin && zt < ztmax)
// sample z
if(samplez)
{
G4double u,cz1;
if(zt >= onethird)
const G4double ztmax = 0.99, onethird = 1./3. ;
G4double zt = zmean/tPathLength ;
if (tPathLength > stepmin && zt < ztmax)
{
G4double cz = 0.5*(3.*zt-1.)/(1.-zt) ;
cz1 = 1.+cz ;
G4double u0 = cz/cz1 ;
G4double grej ;
do {
u = exp(log(G4UniformRand())/cz1) ;
grej = exp(cz*log(u/u0))*(1.-u)/(1.-u0) ;
} while (grej < G4UniformRand()) ;
G4double u,cz1;
if(zt >= onethird)
{
G4double cz = 0.5*(3.*zt-1.)/(1.-zt) ;
cz1 = 1.+cz ;
G4double u0 = cz/cz1 ;
G4double grej ;
do {
u = exp(log(G4UniformRand())/cz1) ;
grej = exp(cz*log(u/u0))*(1.-u)/(1.-u0) ;
} while (grej < G4UniformRand()) ;
}
else
{
cz1 = 1./zt-1.;
u = 1.-exp(log(G4UniformRand())/cz1) ;
}
zPathLength = tPathLength*u ;
}
else
{
cz1 = 1./zt-1.;
u = 1.-exp(log(G4UniformRand())/cz1) ;
}
zPathLength = tPathLength*u ;
}
// G4cout << zPathLength << G4endl;
geomLength = zPathLength;
if(geomLength > lambda0) geomLength = lambda0;
@@ -626,14 +719,14 @@ G4double G4UrbanMscModel::ComputeGeomPathLength(G4double)
G4double G4UrbanMscModel::ComputeTrueStepLength(G4double geomStepLength)
{
// msc stop the step
// step defined other than transportation
if(geomStepLength == geomLength && tPathLength <= currentRange)
return tPathLength;
// recalculation
G4double trueLength = geomStepLength;
zPathLength = geomStepLength;
if((geomStepLength > lambda0*tausmall) && (geomStepLength >= stepmin))
if((geomStepLength > lambda0*tausmall) && (geomStepLength > stepmin))
{
if(par1 < 0.)
trueLength = -lambda0*log(1.-geomStepLength/lambda0) ;
@@ -654,6 +747,32 @@ G4double G4UrbanMscModel::ComputeTrueStepLength(G4double geomStepLength)
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
G4double G4UrbanMscModel::ComputeTheta0(G4double trueStepLength,
G4double KineticEnergy)
{
// for all particles take the width of the central part
// from a parametrization similar to the Highland formula
// ( Highland formula: Particle Physics Booklet, July 2002, eq. 26.10)
const G4double c_highland = 13.6*MeV ;
G4double betacp = sqrt(currentKinEnergy*(currentKinEnergy+2.*mass)*
KineticEnergy*(KineticEnergy+2.*mass)/
((currentKinEnergy+mass)*(KineticEnergy+mass)));
G4double y = trueStepLength/currentRadLength;
G4double theta0 = c_highland*charge*sqrt(y)/betacp;
y = log(y);
theta0 *= sqrt(1.+y*(0.105+0.0035*y));
//correction for small Zeff (based on high energy
// proton scattering data)
// see G.Shen at al. Phys.Rev.D20(1979) p.1584
theta0 *= 1.-0.24/(Zeff*(Zeff+1.));
return theta0;
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
std::vector<G4DynamicParticle*>* G4UrbanMscModel::SampleSecondaries(
const G4MaterialCutsCouple*,
const G4DynamicParticle* dynParticle,
@@ -661,7 +780,7 @@ std::vector<G4DynamicParticle*>* G4UrbanMscModel::SampleSecondaries(
G4double safety)
{
G4double kineticEnergy = dynParticle->GetKineticEnergy();
if(kineticEnergy <= 0.0) return 0;
if((kineticEnergy <= 0.0) || (truestep <= 0.)) return 0;
G4double cth = SampleCosineTheta(truestep,kineticEnergy);
G4double sth = sqrt((1.0 - cth)*(1.0 + cth));
@@ -674,14 +793,6 @@ std::vector<G4DynamicParticle*>* G4UrbanMscModel::SampleSecondaries(
newDirection.rotateUz(oldDirection);
fParticleChange->ProposeMomentumDirection(newDirection);
/*
const G4ParticleDefinition* pd = dynParticle->GetDefinition();
G4cout << "G4UrbanMscModel: Sample secondary; E(MeV)= " << kineticEnergy/MeV
<< " MeV; step(mm)= " << truestep/mm
<< ", safety(mm)= " << safety/mm << " " << pd->GetParticleName()
<< G4endl;
*/
if (latDisplasment) {
G4double r = SampleDisplacement();
@@ -716,23 +827,23 @@ std::vector<G4DynamicParticle*>* G4UrbanMscModel::SampleSecondaries(
{
// ******* we do not have track info at this level ***********
// ******* so navigator is called at boundary too ************
navigator->LocateGlobalPointWithinVolume(Position);
const G4double cstep = safety ;
G4double newsafety = safety;
phi = navigator->ComputeStep(Position,latDirection,
cstep,newsafety);
G4double newsafety= -100.; // = safety;
// newsafety= navigator->ComputeSafety(Position);
newsafety= safetyHelper->ComputeSafety(Position);
safety= newsafety;
if(r < newsafety)
fac = 1.;
else
fac = newsafety/r ;
}
if(fac > 0.)
{
// compute new endpoint of the Step
G4ThreeVector newPosition = Position+fac*r*latDirection;
navigator->LocateGlobalPointWithinVolume(newPosition);
// navigator->LocateGlobalPointWithinVolume(newPosition);
safetyHelper->ReLocateWithinVolume(newPosition);
fParticleChange->ProposePosition(newPosition);
}
@@ -749,19 +860,55 @@ G4double G4UrbanMscModel::SampleCosineTheta(G4double trueStepLength,
G4double cth = 1. ;
G4double tau = trueStepLength/lambda0 ;
if(trueStepLength >= currentRange*dtrl)
if(par1*trueStepLength < 1.)
tau = -par2*log(1.-par1*trueStepLength) ;
else
tau = taubig ;
Zeff = couple->GetMaterial()->GetTotNbOfElectPerVolume()/
couple->GetMaterial()->GetTotNbOfAtomsPerVolume() ;
currentTau = tau ;
lambdaeff = trueStepLength/currentTau;
if(trueStepLength < stepmin)
cth = exp(-currentTau) ;
if((trueStepLength <= stepmin) && (skin > 0.) &&
(geomlimit <= skindepth1))
{
//no scattering, single or plural scattering
// just before boundary crossing only (for skin > 0)
G4double mean = trueStepLength/stepmin ;
cth = 1.;
G4int n = G4Poisson(mean);
if(n > 0)
{
G4double tm = KineticEnergy/mass;
// ascr - screening parameter, factor 0.025 comes from
// requirement of 'smooth' transition msc -> single scattering
G4double ascr = 0.025*exp(log(Zeff)/3.)/(137.*sqrt(tm*(tm+2.)));
G4double ascr1 = 1.+0.5*ascr*ascr;
G4double bp1=ascr1+1.;
G4double bm1=ascr1-1.;
// single scattering from screened Rutherford x-section
G4double ct,st,phi;
G4double sx=0.,sy=0.,sz=0.;
for(G4int i=1; i<=n; i++)
{
ct = ascr1-bp1*bm1/(2.*G4UniformRand()+bm1);
if(ct < -1.) ct = -1.;
if(ct > 1.) ct = 1.;
st = sqrt(1.-ct*ct);
phi = twopi*G4UniformRand();
sx += st*cos(phi);
sy += st*sin(phi);
sz += ct;
}
cth = sz/sqrt(sx*sx+sy*sy+sz*sz);
}
}
else
{
if(trueStepLength >= currentRange*dtrl)
if(par1*trueStepLength < 1.)
tau = -par2*log(1.-par1*trueStepLength) ;
else
tau = taubig ;
currentTau = tau ;
lambdaeff = trueStepLength/currentTau;
currentRadLength = couple->GetMaterial()->GetRadlen();
if (tau >= taubig) cth = -1.+2.*G4UniformRand();
else if (tau >= tausmall)
{
@@ -769,20 +916,9 @@ G4double G4UrbanMscModel::SampleCosineTheta(G4double trueStepLength,
G4double prob = 0., qprob = 1. ;
G4double a = 1., ea = 0., eaa = 1.;
G4double xmean1 = 1., xmean2 = 0.;
G4double xsi = 3.;
// 3 model functions ( normal case)............................
// for all particles take the width of the central part
// from a parametrization similar to the Highland formula
// ( Highland formula: Particle Physics Booklet, July 2002, eq. 26.10)
// here : theta0 = 13.6*MeV*Q*(t/X0)**0.555/(beta*cp)
const G4double xsi = 3., c_highland = 13.26*MeV ;
G4double betacp = sqrt(currentKinEnergy*(currentKinEnergy+2.*mass)*
KineticEnergy*(KineticEnergy+2.*mass)/
((currentKinEnergy+mass)*(KineticEnergy+mass)));
G4double tailpar = c_highland/betacp ;
const G4double corr_highland=0.54;
G4double theta0 = tailpar*charge*exp(corr_highland*
log(trueStepLength/currentRadLength)) ;
G4double theta0 = ComputeTheta0(trueStepLength,KineticEnergy);
if(theta0 > taulim) a = 0.5/(1.-cos(theta0)) ;
else a = 1.0/(theta0*theta0) ;
@@ -793,8 +929,7 @@ G4double G4UrbanMscModel::SampleCosineTheta(G4double trueStepLength,
G4double c1 = c-1.;
G4double x0 = 1.-xsi/a ;
// x0 < ~cos(30 deg)
if(x0 < 0.866)
if(x0 < 0.)
{
// 1 model function
b = exp(tau);
@@ -805,8 +940,12 @@ G4double G4UrbanMscModel::SampleCosineTheta(G4double trueStepLength,
}
else
{
c = xsi-factail*currentRadLength/(lambda0*tailpar*tailpar) ;
if(c <= 2.) c = 2.+taulim ;
//empirical tail parameter
// based some exp. data
c = 2.40-0.027*exp(2.*log(Zeff)/3.);
if(c == 2.) c = 2.+taulim ;
if(c <= 1.) c = 1.+taulim ;
c1 = c-1.;
ea = exp(-xsi) ;
@@ -824,7 +963,7 @@ G4double G4UrbanMscModel::SampleCosineTheta(G4double trueStepLength,
G4double f1x0 = a*ea/eaa ;
G4double f2x0 = c1*eb1*ebx/(eb1-ebx)/exp(c*log(bx)) ;
// from continuity at x=x0
prob = f2x0/(f1x0+f2x0) ;
@@ -907,8 +1046,3 @@ G4double G4UrbanMscModel::LatCorrelation()
}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......