#include <G4SynchrotronRadiation.hh>

Inheritance diagram for G4SynchrotronRadiation:

Public Member Functions
	G4SynchrotronRadiation (const G4String &pName="SynRad", G4ProcessType type=fElectromagnetic)

virtual	~G4SynchrotronRadiation ()

G4double	GetMeanFreePath (const G4Track &track, G4double previousStepSize, G4ForceCondition *condition)

G4VParticleChange *	PostStepDoIt (const G4Track &track, const G4Step &Step)

G4double	GetPhotonEnergy (const G4Track &trackData, const G4Step &stepData)

G4double	GetRandomEnergySR (G4double, G4double)

G4double	InvSynFracInt (G4double x)

G4double	Chebyshev (G4double a, G4double b, const G4double c[], G4int n, G4double x)

G4bool	IsApplicable (const G4ParticleDefinition &)

void	BuildPhysicsTable (const G4ParticleDefinition &)

void	PrintInfoDefinition ()

Public Member Functions inherited from G4VDiscreteProcess
	G4VDiscreteProcess (const G4String &, G4ProcessType aType=fNotDefined)

	G4VDiscreteProcess (G4VDiscreteProcess &)

virtual	~G4VDiscreteProcess ()

virtual G4double	PostStepGetPhysicalInteractionLength (const G4Track &track, G4double previousStepSize, G4ForceCondition *condition)

virtual G4VParticleChange *	PostStepDoIt (const G4Track &, const G4Step &)

virtual G4double	AlongStepGetPhysicalInteractionLength (const G4Track &, G4double, G4double, G4double &, G4GPILSelection *)

virtual G4double	AtRestGetPhysicalInteractionLength (const G4Track &, G4ForceCondition *)

virtual G4VParticleChange *	AtRestDoIt (const G4Track &, const G4Step &)

virtual G4VParticleChange *	AlongStepDoIt (const G4Track &, const G4Step &)

Public Member Functions inherited from G4VProcess
	G4VProcess (const G4String &aName="NoName", G4ProcessType aType=fNotDefined)

	G4VProcess (const G4VProcess &right)

virtual	~G4VProcess ()

G4int	operator== (const G4VProcess &right) const

G4int	operator!= (const G4VProcess &right) const

virtual G4VParticleChange *	PostStepDoIt (const G4Track &track, const G4Step &stepData)=0

virtual G4VParticleChange *	AlongStepDoIt (const G4Track &track, const G4Step &stepData)=0

virtual G4VParticleChange *	AtRestDoIt (const G4Track &track, const G4Step &stepData)=0

virtual G4double	AlongStepGetPhysicalInteractionLength (const G4Track &track, G4double previousStepSize, G4double currentMinimumStep, G4double &proposedSafety, G4GPILSelection *selection)=0

virtual G4double	AtRestGetPhysicalInteractionLength (const G4Track &track, G4ForceCondition *condition)=0

virtual G4double	PostStepGetPhysicalInteractionLength (const G4Track &track, G4double previousStepSize, G4ForceCondition *condition)=0

G4double	GetCurrentInteractionLength () const

void	SetPILfactor (G4double value)

G4double	GetPILfactor () const

G4double	AlongStepGPIL (const G4Track &track, G4double previousStepSize, G4double currentMinimumStep, G4double &proposedSafety, G4GPILSelection *selection)

G4double	AtRestGPIL (const G4Track &track, G4ForceCondition *condition)

G4double	PostStepGPIL (const G4Track &track, G4double previousStepSize, G4ForceCondition *condition)

virtual G4bool	IsApplicable (const G4ParticleDefinition &)

virtual void	BuildPhysicsTable (const G4ParticleDefinition &)

virtual void	PreparePhysicsTable (const G4ParticleDefinition &)

virtual G4bool	StorePhysicsTable (const G4ParticleDefinition *, const G4String &, G4bool)

virtual G4bool	RetrievePhysicsTable (const G4ParticleDefinition *, const G4String &, G4bool)

const G4String &	GetPhysicsTableFileName (const G4ParticleDefinition *, const G4String &directory, const G4String &tableName, G4bool ascii=false)

const G4String &	GetProcessName () const

G4ProcessType	GetProcessType () const

void	SetProcessType (G4ProcessType)

G4int	GetProcessSubType () const

void	SetProcessSubType (G4int)

virtual void	StartTracking (G4Track *)

virtual void	EndTracking ()

virtual void	SetProcessManager (const G4ProcessManager *)

virtual const G4ProcessManager *	GetProcessManager ()

virtual void	ResetNumberOfInteractionLengthLeft ()

G4double	GetNumberOfInteractionLengthLeft () const

G4double	GetTotalNumberOfInteractionLengthTraversed () const

G4bool	isAtRestDoItIsEnabled () const

G4bool	isAlongStepDoItIsEnabled () const

G4bool	isPostStepDoItIsEnabled () const

virtual void	DumpInfo () const

void	SetVerboseLevel (G4int value)

G4int	GetVerboseLevel () const

Additional Inherited Members
Static Public Member Functions inherited from G4VProcess
static const G4String &	GetProcessTypeName (G4ProcessType)

virtual G4double	GetMeanFreePath (const G4Track &aTrack, G4double previousStepSize, G4ForceCondition *condition)=0

Protected Member Functions inherited from G4VProcess
void	SubtractNumberOfInteractionLengthLeft (G4double previousStepSize)

void	ClearNumberOfInteractionLengthLeft ()

Protected Attributes inherited from G4VProcess
const G4ProcessManager *	aProcessManager

G4VParticleChange *	pParticleChange

G4ParticleChange	aParticleChange

G4double	theNumberOfInteractionLengthLeft

G4double	currentInteractionLength

G4double	theInitialNumberOfInteractionLength

G4String	theProcessName

G4String	thePhysicsTableFileName

G4ProcessType	theProcessType

G4int	theProcessSubType

G4double	thePILfactor

G4bool	enableAtRestDoIt

G4bool	enableAlongStepDoIt

G4bool	enablePostStepDoIt

G4int	verboseLevel

Detailed Description

Definition at line 63 of file G4SynchrotronRadiation.hh.

Constructor & Destructor Documentation

◆ G4SynchrotronRadiation()

G4SynchrotronRadiation::G4SynchrotronRadiation	(	const G4String &	pName = `"SynRad"`,
		G4ProcessType	type = `fElectromagnetic`
	)

Definition at line 55 of file G4SynchrotronRadiation.cc.

                     :G4VDiscreteProcess (processName, type),
  theGamma (G4Gamma::Gamma() ),
  theElectron ( G4Electron::Electron() ),
  thePositron ( G4Positron::Positron() )
{
  G4TransportationManager* transportMgr = 
    G4TransportationManager::GetTransportationManager();
 
  fFieldPropagator = transportMgr->GetPropagatorInField();
 
  fLambdaConst = std::sqrt(3.0)*electron_mass_c2/
                           (2.5*fine_structure_const*eplus*c_light);
  fEnergyConst = 1.5*c_light*c_light*eplus*hbar_Planck/electron_mass_c2 ;
 
  SetProcessSubType(fSynchrotronRadiation);
  verboseLevel=1;
}

◆ ~G4SynchrotronRadiation()

G4SynchrotronRadiation::~G4SynchrotronRadiation ( )

virtual

Definition at line 79 of file G4SynchrotronRadiation.cc.

80{}

Member Function Documentation

◆ BuildPhysicsTable()

void G4SynchrotronRadiation::BuildPhysicsTable ( const G4ParticleDefinition & part )

virtual

Reimplemented from G4VProcess.

Definition at line 421 of file G4SynchrotronRadiation.cc.

{
  if(0 < verboseLevel && &part==theElectron ) PrintInfoDefinition();
}

◆ Chebyshev()

G4double G4SynchrotronRadiation::Chebyshev	(	G4double	a,
		G4double	b,
		const G4double	c[],
		G4int	n,
		G4double	x
	)

inline

Definition at line 117 of file G4SynchrotronRadiation.hh.

{
  G4double y;
  G4double y2=2.0*(y=(2.0*x-a-b)/(b-a)); // Change of variable.
  G4double d=0,dd=0;
  for (G4int j=n-1;j>=1;--j) // Clenshaw's recurrence.
  { G4double sv=d;
    d=y2*d-dd+c[j];
    dd=sv;
  }
  return y*d-dd+0.5*c[0];
}

Referenced by InvSynFracInt().

◆ GetMeanFreePath()

G4double G4SynchrotronRadiation::GetMeanFreePath	(	const G4Track &	track,
		G4double	previousStepSize,
		G4ForceCondition *	condition
	)

virtual

Implements G4VDiscreteProcess.

Definition at line 91 of file G4SynchrotronRadiation.cc.

{
  // gives the MeanFreePath in GEANT4 internal units
  G4double MeanFreePath;
 
  const G4DynamicParticle* aDynamicParticle = trackData.GetDynamicParticle();
 
  *condition = NotForced;
 
  G4double gamma = aDynamicParticle->GetTotalEnergy()/
                   aDynamicParticle->GetMass();
 
  G4double particleCharge = aDynamicParticle->GetDefinition()->GetPDGCharge();
 
  if ( gamma < 1.0e3 )  MeanFreePath = DBL_MAX;
  else
  {
 
    G4ThreeVector  FieldValue;
    const G4Field*   pField = 0;
 
    G4FieldManager* fieldMgr=0;
    G4bool          fieldExertsForce = false;
 
    if( (particleCharge != 0.0) )
    {
      fieldMgr = fFieldPropagator->FindAndSetFieldManager( trackData.GetVolume() );
 
      if ( fieldMgr != 0 )
      {
        // If the field manager has no field, there is no field !
 
        fieldExertsForce = ( fieldMgr->GetDetectorField() != 0 );
      }
    }
    if ( fieldExertsForce )
    {
      pField = fieldMgr->GetDetectorField();
      G4ThreeVector  globPosition = trackData.GetPosition();
 
      G4double  globPosVec[4], FieldValueVec[6];
 
      globPosVec[0] = globPosition.x();
      globPosVec[1] = globPosition.y();
      globPosVec[2] = globPosition.z();
      globPosVec[3] = trackData.GetGlobalTime();
 
      pField->GetFieldValue( globPosVec, FieldValueVec );
 
      FieldValue = G4ThreeVector( FieldValueVec[0],
                                   FieldValueVec[1],
                                   FieldValueVec[2]   );
 
 
 
      G4ThreeVector unitMomentum = aDynamicParticle->GetMomentumDirection();
      G4ThreeVector unitMcrossB  = FieldValue.cross(unitMomentum);
      G4double perpB             = unitMcrossB.mag();
 
      if( perpB > 0.0 ) MeanFreePath = fLambdaConst/perpB;
      else              MeanFreePath = DBL_MAX;
 
      static G4bool FirstTime=true;
      if(verboseLevel > 0 && FirstTime)
      {
        G4cout << "G4SynchrotronRadiation::GetMeanFreePath :" << '\n' 
           << "  MeanFreePath = " << G4BestUnit(MeanFreePath, "Length")
           << G4endl;
        if(verboseLevel > 1)
        {
          G4ThreeVector pvec=aDynamicParticle->GetMomentum();
          G4double Btot=FieldValue.getR();
          G4double ptot=pvec.getR();
          G4double rho= ptot / (MeV * c_light * Btot ); // full bending radius
          G4double Theta=unitMomentum.theta(FieldValue); // angle between particle and field
          G4cout
            << "  B = " << Btot/tesla << " Tesla"
            << "  perpB = " << perpB/tesla << " Tesla"
            << "  Theta = " << Theta << " std::sin(Theta)=" << std::sin(Theta) << '\n'
            << "  ptot  = " << G4BestUnit(ptot,"Energy")
            << "  rho   = " << G4BestUnit(rho,"Length")
            << G4endl;
        }
    FirstTime=false;
      }
    }
    else  MeanFreePath = DBL_MAX;
 
 
  }
 
  return MeanFreePath;
}

◆ GetPhotonEnergy()

G4double G4SynchrotronRadiation::GetPhotonEnergy	(	const G4Track &	trackData,
		const G4Step &	stepData
	)

◆ GetRandomEnergySR()

G4double G4SynchrotronRadiation::GetRandomEnergySR	(	G4double	gamma,
		G4double	perpB
	)

Definition at line 398 of file G4SynchrotronRadiation.cc.

{
 
  G4double Ecr=fEnergyConst*gamma*gamma*perpB;
 
  static G4bool FirstTime=true;
  if(verboseLevel > 0 && FirstTime)
  { G4double Emean=8./(15.*std::sqrt(3.))*Ecr; // mean photon energy
    G4double E_rms=std::sqrt(211./675.)*Ecr; // rms of photon energy distribution
    G4int prec = G4cout.precision();
    G4cout << "G4SynchrotronRadiation::GetRandomEnergySR :" << '\n' << std::setprecision(4)
    << "  Ecr   = "    << G4BestUnit(Ecr,"Energy") << '\n'
    << "  Emean = "    << G4BestUnit(Emean,"Energy") << '\n'
    << "  E_rms = "    << G4BestUnit(E_rms,"Energy") << G4endl;
    FirstTime=false;
    G4cout.precision(prec); 
  }
 
  G4double energySR=Ecr*InvSynFracInt(G4UniformRand());
  return energySR;
}

Referenced by PostStepDoIt().

◆ InvSynFracInt()

G4double G4SynchrotronRadiation::InvSynFracInt ( G4double x )

Definition at line 339 of file G4SynchrotronRadiation.cc.

{
  // from 0 to 0.7
  const G4double aa1=0  ,aa2=0.7;
  const G4int ncheb1=27;
  static const G4double cheb1[] =
  { 1.22371665676046468821,0.108956475422163837267,0.0383328524358594396134,0.00759138369340257753721,
   0.00205712048644963340914,0.000497810783280019308661,0.000130743691810302187818,0.0000338168760220395409734,
   8.97049680900520817728e-6,2.38685472794452241466e-6,6.41923109149104165049e-7,1.73549898982749277843e-7,
   4.72145949240790029153e-8,1.29039866111999149636e-8,3.5422080787089834182e-9,9.7594757336403784905e-10,
   2.6979510184976065731e-10,7.480422622550977077e-11,2.079598176402699913e-11,5.79533622220841193e-12,
   1.61856011449276096e-12,4.529450993473807e-13,1.2698603951096606e-13,3.566117394511206e-14,1.00301587494091e-14,
   2.82515346447219e-15,7.9680747949792e-16};
  //   from 0.7 to 0.9132260271183847
  const G4double aa3=0.9132260271183847;
  const G4int ncheb2=27;
  static const G4double cheb2[] =
  { 1.1139496701107756,0.3523967429328067,0.0713849171926623,0.01475818043595387,0.003381255637322462,
    0.0008228057599452224,0.00020785506681254216,0.00005390169253706556,0.000014250571923902464,3.823880733161044e-6,
    1.0381966089136036e-6,2.8457557457837253e-7,7.86223332179956e-8,2.1866609342508474e-8,6.116186259857143e-9,
    1.7191233618437565e-9,4.852755117740807e-10,1.3749966961763457e-10,3.908961987062447e-11,1.1146253766895824e-11,
    3.1868887323415814e-12,9.134319791300977e-13,2.6211077371181566e-13,7.588643377757906e-14,2.1528376972619e-14,
    6.030906040404772e-15,1.9549163926819867e-15};
   // Chebyshev with exp/log  scale
   // a = -Log[1 - SynFracInt[1]]; b = -Log[1 - SynFracInt[7]];
  const G4double aa4=2.4444485538746025480,aa5=9.3830728608909477079;
  const G4int ncheb3=28;
  static const G4double cheb3[] =
  { 1.2292683840435586977,0.160353449247864455879,-0.0353559911947559448721,0.00776901561223573936985,
   -0.00165886451971685133259,0.000335719118906954279467,-0.0000617184951079161143187,9.23534039743246708256e-6,
   -6.06747198795168022842e-7,-3.07934045961999778094e-7,1.98818772614682367781e-7,-8.13909971567720135413e-8,
   2.84298174969641838618e-8,-9.12829766621316063548e-9,2.77713868004820551077e-9,-8.13032767247834023165e-10,
   2.31128525568385247392e-10,-6.41796873254200220876e-11,1.74815310473323361543e-11,-4.68653536933392363045e-12,
   1.24016595805520752748e-12,-3.24839432979935522159e-13,8.44601465226513952994e-14,-2.18647276044246803998e-14,
   5.65407548745690689978e-15,-1.46553625917463067508e-15,3.82059606377570462276e-16,-1.00457896653436912508e-16};
  const G4double aa6=33.122936966163038145;
  const G4int ncheb4=27;
  static const G4double cheb4[] =
  {1.69342658227676741765,0.0742766400841232319225,-0.019337880608635717358,0.00516065527473364110491,
   -0.00139342012990307729473,0.000378549864052022522193,-0.000103167085583785340215,0.0000281543441271412178337,
   -7.68409742018258198651e-6,2.09543221890204537392e-6,-5.70493140367526282946e-7,1.54961164548564906446e-7,
   -4.19665599629607704794e-8,1.13239680054166507038e-8,-3.04223563379021441863e-9,8.13073745977562957997e-10,
   -2.15969415476814981374e-10,5.69472105972525594811e-11,-1.48844799572430829499e-11,3.84901514438304484973e-12,
   -9.82222575944247161834e-13,2.46468329208292208183e-13,-6.04953826265982691612e-14,1.44055805710671611984e-14,
   -3.28200813577388740722e-15,6.96566359173765367675e-16,-1.294122794852896275e-16};
 
  if(x<aa2)      return x*x*x*Chebyshev(aa1,aa2,cheb1,ncheb1,x);
  else if(x<aa3) return       Chebyshev(aa2,aa3,cheb2,ncheb2,x);
  else if(x<1-0.0000841363)
  { G4double y=-std::log(1-x);
    return y*Chebyshev(aa4,aa5,cheb3,ncheb3,y);
  }
  else
  { G4double y=-std::log(1-x);
    return y*Chebyshev(aa5,aa6,cheb4,ncheb4,y);
  }
}

Referenced by GetRandomEnergySR().

◆ IsApplicable()

G4bool G4SynchrotronRadiation::IsApplicable ( const G4ParticleDefinition & particle )

inlinevirtual

Reimplemented from G4VProcess.

Definition at line 109 of file G4SynchrotronRadiation.hh.

{
 
  return ( ( &particle == (const G4ParticleDefinition *)theElectron ) ||
           ( &particle == (const G4ParticleDefinition *)thePositron )    );
}

◆ PostStepDoIt()

G4VParticleChange * G4SynchrotronRadiation::PostStepDoIt	(	const G4Track &	track,
		const G4Step &	Step
	)

virtual

Reimplemented from G4VDiscreteProcess.

Definition at line 192 of file G4SynchrotronRadiation.cc.

{
  aParticleChange.Initialize(trackData);
 
  const G4DynamicParticle* aDynamicParticle=trackData.GetDynamicParticle();
 
  G4double gamma = aDynamicParticle->GetTotalEnergy()/
                   (aDynamicParticle->GetMass()              );
 
  if(gamma <= 1.0e3 ) 
  {
    return G4VDiscreteProcess::PostStepDoIt(trackData,stepData);
  }
  G4double particleCharge = aDynamicParticle->GetDefinition()->GetPDGCharge();
 
  G4ThreeVector  FieldValue;
  const G4Field*   pField = 0;
 
  G4FieldManager* fieldMgr=0;
  G4bool          fieldExertsForce = false;
 
  if( (particleCharge != 0.0) )
  {
    fieldMgr = fFieldPropagator->FindAndSetFieldManager( trackData.GetVolume() );
    if ( fieldMgr != 0 )
    {
      // If the field manager has no field, there is no field !
 
      fieldExertsForce = ( fieldMgr->GetDetectorField() != 0 );
    }
  }
  if ( fieldExertsForce )
  {
    pField = fieldMgr->GetDetectorField();
    G4ThreeVector  globPosition = trackData.GetPosition();
    G4double  globPosVec[4], FieldValueVec[6];
    globPosVec[0] = globPosition.x();
    globPosVec[1] = globPosition.y();
    globPosVec[2] = globPosition.z();
    globPosVec[3] = trackData.GetGlobalTime();
 
    pField->GetFieldValue( globPosVec, FieldValueVec );
    FieldValue = G4ThreeVector( FieldValueVec[0],
                                   FieldValueVec[1],
                                   FieldValueVec[2]   );
 
    G4ThreeVector unitMomentum = aDynamicParticle->GetMomentumDirection();
    G4ThreeVector unitMcrossB = FieldValue.cross(unitMomentum);
    G4double perpB = unitMcrossB.mag();
    if(perpB > 0.0)
    {
      // M-C of synchrotron photon energy
 
      G4double energyOfSR = GetRandomEnergySR(gamma,perpB);
 
      // check against insufficient energy
 
      if( energyOfSR <= 0.0 )
      {
        return G4VDiscreteProcess::PostStepDoIt(trackData,stepData);
      }
      G4double kineticEnergy = aDynamicParticle->GetKineticEnergy();
      G4ParticleMomentum
      particleDirection = aDynamicParticle->GetMomentumDirection();
 
      // M-C of its direction, simplified dipole boosted approach
 
      // G4double Teta, fteta;  // = G4UniformRand()/gamma;    // Very roughly
 
      G4double cosTheta, sinTheta, fcos, beta;
 
  do
  { 
    cosTheta = 1. - 2.*G4UniformRand();
    fcos     = (1 + cosTheta*cosTheta)*0.5;
  }
  while( fcos < G4UniformRand() );
 
  beta = std::sqrt(1. - 1./(gamma*gamma));
 
  cosTheta = (cosTheta + beta)/(1. + beta*cosTheta);
 
  if( cosTheta >  1. ) cosTheta =  1.;
  if( cosTheta < -1. ) cosTheta = -1.;
 
  sinTheta = std::sqrt(1. - cosTheta*cosTheta );
 
      G4double Phi  = twopi * G4UniformRand();
 
      G4double dirx = sinTheta*std::cos(Phi) ,
               diry = sinTheta*std::sin(Phi) ,
               dirz = cosTheta;
 
      G4ThreeVector gammaDirection ( dirx, diry, dirz);
      gammaDirection.rotateUz(particleDirection);
 
      // polarization of new gamma
 
      // G4double sx =  std::cos(Teta)*std::cos(Phi);
      // G4double sy =  std::cos(Teta)*std::sin(Phi);
      // G4double sz = -std::sin(Teta);
 
      G4ThreeVector gammaPolarization = FieldValue.cross(gammaDirection);
      gammaPolarization = gammaPolarization.unit();
 
      // (sx, sy, sz);
      // gammaPolarization.rotateUz(particleDirection);
 
      // create G4DynamicParticle object for the SR photon
 
      G4DynamicParticle* aGamma= new G4DynamicParticle ( theGamma,
                                                         gammaDirection,
                                                         energyOfSR      );
      aGamma->SetPolarization( gammaPolarization.x(),
                               gammaPolarization.y(),
                               gammaPolarization.z() );
 
 
      aParticleChange.SetNumberOfSecondaries(1);
      aParticleChange.AddSecondary(aGamma);
 
      // Update the incident particle
 
      G4double newKinEnergy = kineticEnergy - energyOfSR;
      aParticleChange.ProposeLocalEnergyDeposit (0.);
 
      if (newKinEnergy > 0.)
      {
        aParticleChange.ProposeMomentumDirection( particleDirection );
        aParticleChange.ProposeEnergy( newKinEnergy );
      }
      else
      {
        aParticleChange.ProposeEnergy( 0. );
      }
    }
  }
  return G4VDiscreteProcess::PostStepDoIt(trackData,stepData);
}

◆ PrintInfoDefinition()

void G4SynchrotronRadiation::PrintInfoDefinition ( )

Definition at line 426 of file G4SynchrotronRadiation.cc.

{
  G4String comments ="Incoherent Synchrotron Radiation\n";
  G4cout << G4endl << GetProcessName() << ":  " << comments
         << "      good description for long magnets at all energies" << G4endl;
}

Referenced by BuildPhysicsTable().

The documentation for this class was generated from the following files:

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ G4SynchrotronRadiation()

◆ ~G4SynchrotronRadiation()

Member Function Documentation

◆ BuildPhysicsTable()

◆ Chebyshev()

◆ GetMeanFreePath()

◆ GetPhotonEnergy()

◆ GetRandomEnergySR()

◆ InvSynFracInt()

◆ IsApplicable()

◆ PostStepDoIt()

◆ PrintInfoDefinition()