Geant4-11
Public Member Functions | Protected Member Functions | Private Attributes | Static Private Attributes
G4HelixHeum Class Reference

#include <G4HelixHeum.hh>

Inheritance diagram for G4HelixHeum:
G4MagHelicalStepper G4MagIntegratorStepper

Public Member Functions

G4double DistChord () const
 
void DumbStepper (const G4double y[], G4ThreeVector Bfld, G4double h, G4double yout[])
 
 G4HelixHeum (G4Mag_EqRhs *EqRhs)
 
G4EquationOfMotionGetEquationOfMotion ()
 
const G4EquationOfMotionGetEquationOfMotion () const
 
unsigned long GetfNoRHSCalls ()
 
G4int GetNumberOfStateVariables () const
 
G4int GetNumberOfVariables () const
 
G4int IntegrationOrder ()
 
G4int IntegratorOrder () const
 
G4bool IsFSAL () const
 
void NormalisePolarizationVector (G4double vec[12])
 
void NormaliseTangentVector (G4double vec[6])
 
void ResetfNORHSCalls ()
 
void RightHandSide (const G4double y[], G4double dydx[]) const
 
void RightHandSide (const G4double y[], G4double dydx[], G4double field[]) const
 
void SetEquationOfMotion (G4EquationOfMotion *newEquation)
 
virtual void Stepper (const G4double y[], const G4double dydx[], G4double h, G4double yout[], G4double yerr[])
 
 ~G4HelixHeum ()
 

Protected Member Functions

void AdvanceHelix (const G4double yIn[], G4ThreeVector Bfld, G4double h, G4double yHelix[], G4double yHelix2[]=0)
 
G4double GetAngCurve () const
 
G4double GetCurve () const
 
G4double GetInverseCurve (const G4double Momentum, const G4double Bmag)
 
G4double GetRadHelix () const
 
void LinearStep (const G4double yIn[], G4double h, G4double yHelix[]) const
 
void MagFieldEvaluate (const G4double y[], G4ThreeVector &Bfield)
 
void SetAngCurve (const G4double Ang)
 
void SetCurve (const G4double Curve)
 
void SetFSAL (G4bool flag=true)
 
void SetIntegrationOrder (G4int order)
 
void SetRadHelix (const G4double Rad)
 

Private Attributes

G4double fAngCurve = 0.0
 
G4EquationOfMotionfEquation_Rhs = nullptr
 
G4int fIntegrationOrder = -1
 
G4bool fIsFSAL = false
 
const G4int fNoIntegrationVariables = 0
 
unsigned long fNoRHSCalls = 0UL
 
const G4int fNoStateVariables = 0
 
G4Mag_EqRhsfPtrMagEqOfMot = nullptr
 
G4double frCurve = 0.0
 
G4double frHelix = 0.0
 
G4ThreeVector yFinal
 
G4ThreeVector yInitial
 
G4ThreeVector yMidPoint
 

Static Private Attributes

static const G4double fUnitConstant = 0.299792458*(GeV/(tesla*m))
 

Detailed Description

Definition at line 43 of file G4HelixHeum.hh.

Constructor & Destructor Documentation

◆ G4HelixHeum()

G4HelixHeum::G4HelixHeum ( G4Mag_EqRhs EqRhs)

Definition at line 41 of file G4HelixHeum.cc.

42 : G4MagHelicalStepper(EqRhs)
43{
44}
G4MagHelicalStepper(G4Mag_EqRhs *EqRhs)

◆ ~G4HelixHeum()

G4HelixHeum::~G4HelixHeum ( )

Definition at line 46 of file G4HelixHeum.cc.

47{
48}

Member Function Documentation

◆ AdvanceHelix()

void G4MagHelicalStepper::AdvanceHelix ( const G4double  yIn[],
G4ThreeVector  Bfld,
G4double  h,
G4double  yHelix[],
G4double  yHelix2[] = 0 
)
protectedinherited

Definition at line 57 of file G4MagHelicalStepper.cc.

62{
63 // const G4int nvar = 6;
64
65 // OLD const G4double approc_limit = 0.05;
66 // OLD approc_limit = 0.05 gives max.error=x^5/5!=(0.05)^5/5!=2.6*e-9
67 // NEW approc_limit = 0.005 gives max.error=x^5/5!=2.6*e-14
68
69 const G4double approc_limit = 0.005;
70 G4ThreeVector Bnorm, B_x_P, vperp, vpar;
71
72 G4double B_d_P;
73 G4double B_v_P;
74 G4double Theta;
75 G4double R_1;
76 G4double R_Helix;
77 G4double CosT2, SinT2, CosT, SinT;
78 G4ThreeVector positionMove, endTangent;
79
80 G4double Bmag = Bfld.mag();
81 const G4double* pIn = yIn+3;
82 G4ThreeVector initVelocity = G4ThreeVector( pIn[0], pIn[1], pIn[2]);
83 G4double velocityVal = initVelocity.mag();
84 G4ThreeVector initTangent = (1.0/velocityVal) * initVelocity;
85
86 R_1 = GetInverseCurve(velocityVal,Bmag);
87
88 // for too small magnetic fields there is no curvature
89 // (include momentum here) FIXME
90
91 if( (std::fabs(R_1) < 1e-10)||(Bmag<1e-12) )
92 {
93 LinearStep( yIn, h, yHelix );
94
95 // Store and/or calculate parameters for chord distance
96
97 SetAngCurve(1.);
98 SetCurve(h);
99 SetRadHelix(0.);
100 }
101 else
102 {
103 Bnorm = (1.0/Bmag)*Bfld;
104
105 // calculate the direction of the force
106
107 B_x_P = Bnorm.cross(initTangent);
108
109 // parallel and perp vectors
110
111 B_d_P = Bnorm.dot(initTangent); // this is the fraction of P parallel to B
112
113 vpar = B_d_P * Bnorm; // the component parallel to B
114 vperp= initTangent - vpar; // the component perpendicular to B
115
116 B_v_P = std::sqrt( 1 - B_d_P * B_d_P); // Fraction of P perp to B
117
118 // calculate the stepping angle
119
120 Theta = R_1 * h; // * B_v_P;
121
122 // Trigonometrix
123
124 if( std::fabs(Theta) > approc_limit )
125 {
126 SinT = std::sin(Theta);
127 CosT = std::cos(Theta);
128 }
129 else
130 {
131 G4double Theta2 = Theta*Theta;
132 G4double Theta3 = Theta2 * Theta;
133 G4double Theta4 = Theta2 * Theta2;
134 SinT = Theta - 1.0/6.0 * Theta3;
135 CosT = 1 - 0.5 * Theta2 + 1.0/24.0 * Theta4;
136 }
137
138 // the actual "rotation"
139
140 G4double R = 1.0 / R_1;
141
142 positionMove = R * ( SinT * vperp + (1-CosT) * B_x_P) + h * vpar;
143 endTangent = CosT * vperp + SinT * B_x_P + vpar;
144
145 // Store the resulting position and tangent
146
147 yHelix[0] = yIn[0] + positionMove.x();
148 yHelix[1] = yIn[1] + positionMove.y();
149 yHelix[2] = yIn[2] + positionMove.z();
150 yHelix[3] = velocityVal * endTangent.x();
151 yHelix[4] = velocityVal * endTangent.y();
152 yHelix[5] = velocityVal * endTangent.z();
153
154 // Store 2*h step Helix if exist
155
156 if(yHelix2)
157 {
158 SinT2 = 2.0 * SinT * CosT;
159 CosT2 = 1.0 - 2.0 * SinT * SinT;
160 endTangent = (CosT2 * vperp + SinT2 * B_x_P + vpar);
161 positionMove = R * ( SinT2 * vperp + (1-CosT2) * B_x_P) + h*2 * vpar;
162
163 yHelix2[0] = yIn[0] + positionMove.x();
164 yHelix2[1] = yIn[1] + positionMove.y();
165 yHelix2[2] = yIn[2] + positionMove.z();
166 yHelix2[3] = velocityVal * endTangent.x();
167 yHelix2[4] = velocityVal * endTangent.y();
168 yHelix2[5] = velocityVal * endTangent.z();
169 }
170
171 // Store and/or calculate parameters for chord distance
172
173 G4double ptan=velocityVal*B_v_P;
174
175 G4double particleCharge = fPtrMagEqOfMot->FCof() / (eplus*c_light);
176 R_Helix =std::abs( ptan/(fUnitConstant * particleCharge*Bmag));
177
178 SetAngCurve(std::abs(Theta));
179 SetCurve(std::abs(R));
180 SetRadHelix(R_Helix);
181 }
182}
static constexpr double eplus
Definition: G4SIunits.hh:184
CLHEP::Hep3Vector G4ThreeVector
double G4double
Definition: G4Types.hh:83
double z() const
double x() const
double y() const
Hep3Vector cross(const Hep3Vector &) const
double dot(const Hep3Vector &) const
double mag() const
static const G4double fUnitConstant
void SetCurve(const G4double Curve)
void SetRadHelix(const G4double Rad)
G4double GetInverseCurve(const G4double Momentum, const G4double Bmag)
void LinearStep(const G4double yIn[], G4double h, G4double yHelix[]) const
void SetAngCurve(const G4double Ang)
G4double FCof() const
Definition: G4Mag_EqRhs.hh:62
float c_light
Definition: hepunit.py:256

References source.hepunit::c_light, CLHEP::Hep3Vector::cross(), CLHEP::Hep3Vector::dot(), eplus, G4Mag_EqRhs::FCof(), G4MagHelicalStepper::fPtrMagEqOfMot, G4MagHelicalStepper::fUnitConstant, G4MagHelicalStepper::GetInverseCurve(), G4MagHelicalStepper::LinearStep(), CLHEP::Hep3Vector::mag(), G4MagHelicalStepper::SetAngCurve(), G4MagHelicalStepper::SetCurve(), G4MagHelicalStepper::SetRadHelix(), CLHEP::Hep3Vector::x(), CLHEP::Hep3Vector::y(), and CLHEP::Hep3Vector::z().

Referenced by G4ExactHelixStepper::DumbStepper(), G4HelixExplicitEuler::DumbStepper(), DumbStepper(), G4HelixImplicitEuler::DumbStepper(), G4HelixMixedStepper::DumbStepper(), G4HelixSimpleRunge::DumbStepper(), G4HelixExplicitEuler::Stepper(), G4ExactHelixStepper::Stepper(), and G4HelixMixedStepper::Stepper().

◆ DistChord()

G4double G4MagHelicalStepper::DistChord ( ) const
virtualinherited

Implements G4MagIntegratorStepper.

Definition at line 235 of file G4MagHelicalStepper.cc.

236{
237 // Check whether h/R > pi !!
238 // Method DistLine is good only for < pi
239
240 G4double Ang=GetAngCurve();
241 if(Ang<=pi)
242 {
243 return GetRadHelix()*(1-std::cos(0.5*Ang));
244 }
245 else
246 {
247 if(Ang<twopi)
248 {
249 return GetRadHelix()*(1+std::cos(0.5*(twopi-Ang)));
250 }
251 else // return Diameter of projected circle
252 {
253 return 2*GetRadHelix();
254 }
255 }
256}
static constexpr double twopi
Definition: G4SIunits.hh:56
static constexpr double pi
Definition: G4SIunits.hh:55
G4double GetRadHelix() const
G4double GetAngCurve() const

References G4MagHelicalStepper::GetAngCurve(), G4MagHelicalStepper::GetRadHelix(), pi, and twopi.

◆ DumbStepper()

void G4HelixHeum::DumbStepper ( const G4double  y[],
G4ThreeVector  Bfld,
G4double  h,
G4double  yout[] 
)
virtual

Implements G4MagHelicalStepper.

Definition at line 51 of file G4HelixHeum.cc.

55{
56 const G4int nvar = 6 ;
57
58 G4ThreeVector Bfield_Temp, Bfield_Temp2;
59 G4double yTemp[6], yAdd1[6], yAdd2[6] , yTemp2[6];
60
61 AdvanceHelix( yIn, Bfld, h, yAdd1 );
62
63 AdvanceHelix( yIn, Bfld, h/3.0, yTemp );
64 MagFieldEvaluate(yTemp,Bfield_Temp);
65
66 AdvanceHelix( yIn, Bfield_Temp, (2.0 / 3.0) * h, yTemp2 );
67
68 MagFieldEvaluate(yTemp2,Bfield_Temp2);
69
70 AdvanceHelix( yIn, Bfield_Temp2, h, yAdd2 );
71
72 for( G4int i = 0; i < nvar; ++i )
73 {
74 yOut[i] = ( 0.25 * yAdd1[i] + 0.75 * yAdd2[i]);
75 }
76
77 // NormaliseTangentVector( yOut );
78}
int G4int
Definition: G4Types.hh:85
void AdvanceHelix(const G4double yIn[], G4ThreeVector Bfld, G4double h, G4double yHelix[], G4double yHelix2[]=0)
void MagFieldEvaluate(const G4double y[], G4ThreeVector &Bfield)

References G4MagHelicalStepper::AdvanceHelix(), and G4MagHelicalStepper::MagFieldEvaluate().

◆ GetAngCurve()

G4double G4MagHelicalStepper::GetAngCurve ( ) const
inlineprotectedinherited

◆ GetCurve()

G4double G4MagHelicalStepper::GetCurve ( ) const
inlineprotectedinherited

◆ GetEquationOfMotion() [1/2]

G4EquationOfMotion * G4MagIntegratorStepper::GetEquationOfMotion ( )
inlineinherited

◆ GetEquationOfMotion() [2/2]

const G4EquationOfMotion * G4MagIntegratorStepper::GetEquationOfMotion ( ) const
inlineinherited

◆ GetfNoRHSCalls()

unsigned long G4MagIntegratorStepper::GetfNoRHSCalls ( )
inlineinherited

◆ GetInverseCurve()

G4double G4MagHelicalStepper::GetInverseCurve ( const G4double  Momentum,
const G4double  Bmag 
)
inlineprotectedinherited

◆ GetNumberOfStateVariables()

G4int G4MagIntegratorStepper::GetNumberOfStateVariables ( ) const
inlineinherited

◆ GetNumberOfVariables()

G4int G4MagIntegratorStepper::GetNumberOfVariables ( ) const
inlineinherited

◆ GetRadHelix()

G4double G4MagHelicalStepper::GetRadHelix ( ) const
inlineprotectedinherited

◆ IntegrationOrder()

G4int G4MagIntegratorStepper::IntegrationOrder ( )
inlineinherited

◆ IntegratorOrder()

G4int G4HelixHeum::IntegratorOrder ( ) const
inlinevirtual

Implements G4MagIntegratorStepper.

Definition at line 58 of file G4HelixHeum.hh.

58{ return 2; }

◆ IsFSAL()

G4bool G4MagIntegratorStepper::IsFSAL ( ) const
inlineinherited

◆ LinearStep()

void G4MagHelicalStepper::LinearStep ( const G4double  yIn[],
G4double  h,
G4double  yHelix[] 
) const
inlineprotectedinherited

◆ MagFieldEvaluate()

void G4MagHelicalStepper::MagFieldEvaluate ( const G4double  y[],
G4ThreeVector Bfield 
)
inlineprotectedinherited

◆ NormalisePolarizationVector()

void G4MagIntegratorStepper::NormalisePolarizationVector ( G4double  vec[12])
inlineinherited

◆ NormaliseTangentVector()

void G4MagIntegratorStepper::NormaliseTangentVector ( G4double  vec[6])
inlineinherited

◆ ResetfNORHSCalls()

void G4MagIntegratorStepper::ResetfNORHSCalls ( )
inlineinherited

◆ RightHandSide() [1/2]

void G4MagIntegratorStepper::RightHandSide ( const G4double  y[],
G4double  dydx[] 
) const
inlineinherited

◆ RightHandSide() [2/2]

void G4MagIntegratorStepper::RightHandSide ( const G4double  y[],
G4double  dydx[],
G4double  field[] 
) const
inlineinherited

◆ SetAngCurve()

void G4MagHelicalStepper::SetAngCurve ( const G4double  Ang)
inlineprotectedinherited

◆ SetCurve()

void G4MagHelicalStepper::SetCurve ( const G4double  Curve)
inlineprotectedinherited

◆ SetEquationOfMotion()

void G4MagIntegratorStepper::SetEquationOfMotion ( G4EquationOfMotion newEquation)
inlineinherited

◆ SetFSAL()

void G4MagIntegratorStepper::SetFSAL ( G4bool  flag = true)
inlineprotectedinherited

◆ SetIntegrationOrder()

void G4MagIntegratorStepper::SetIntegrationOrder ( G4int  order)
inlineprotectedinherited

◆ SetRadHelix()

void G4MagHelicalStepper::SetRadHelix ( const G4double  Rad)
inlineprotectedinherited

◆ Stepper()

void G4MagHelicalStepper::Stepper ( const G4double  y[],
const G4double  dydx[],
G4double  h,
G4double  yout[],
G4double  yerr[] 
)
virtualinherited

Implements G4MagIntegratorStepper.

Reimplemented in G4ExactHelixStepper, and G4HelixMixedStepper.

Definition at line 188 of file G4MagHelicalStepper.cc.

193{
194 const G4int nvar = 6;
195
196 // correction for Richardson Extrapolation.
197 // G4double correction = 1. / ( (1 << IntegratorOrder()) -1 );
198
199 G4double yTemp[8], yIn[8] ;
200 G4ThreeVector Bfld_initial, Bfld_midpoint;
201
202 // Saving yInput because yInput and yOut can be aliases for same array
203 //
204 for(G4int i=0; i<nvar; ++i)
205 {
206 yIn[i]=yInput[i];
207 }
208
209 G4double h = hstep * 0.5;
210
211 MagFieldEvaluate(yIn, Bfld_initial) ;
212
213 // Do two half steps
214 //
215 DumbStepper(yIn, Bfld_initial, h, yTemp);
216 MagFieldEvaluate(yTemp, Bfld_midpoint) ;
217 DumbStepper(yTemp, Bfld_midpoint, h, yOut);
218
219 // Do a full Step
220 //
221 h = hstep ;
222 DumbStepper(yIn, Bfld_initial, h, yTemp);
223
224 // Error estimation
225 //
226 for(G4int i=0; i<nvar; ++i)
227 {
228 yErr[i] = yOut[i] - yTemp[i] ;
229 }
230
231 return;
232}
virtual void DumbStepper(const G4double y[], G4ThreeVector Bfld, G4double h, G4double yout[])=0

References G4MagHelicalStepper::DumbStepper(), and G4MagHelicalStepper::MagFieldEvaluate().

Field Documentation

◆ fAngCurve

G4double G4MagHelicalStepper::fAngCurve = 0.0
privateinherited

Definition at line 120 of file G4MagHelicalStepper.hh.

◆ fEquation_Rhs

G4EquationOfMotion* G4MagIntegratorStepper::fEquation_Rhs = nullptr
privateinherited

Definition at line 124 of file G4MagIntegratorStepper.hh.

◆ fIntegrationOrder

G4int G4MagIntegratorStepper::fIntegrationOrder = -1
privateinherited

Definition at line 134 of file G4MagIntegratorStepper.hh.

◆ fIsFSAL

G4bool G4MagIntegratorStepper::fIsFSAL = false
privateinherited

Definition at line 136 of file G4MagIntegratorStepper.hh.

◆ fNoIntegrationVariables

const G4int G4MagIntegratorStepper::fNoIntegrationVariables = 0
privateinherited

Definition at line 125 of file G4MagIntegratorStepper.hh.

◆ fNoRHSCalls

unsigned long G4MagIntegratorStepper::fNoRHSCalls = 0UL
mutableprivateinherited

Definition at line 128 of file G4MagIntegratorStepper.hh.

◆ fNoStateVariables

const G4int G4MagIntegratorStepper::fNoStateVariables = 0
privateinherited

Definition at line 126 of file G4MagIntegratorStepper.hh.

◆ fPtrMagEqOfMot

G4Mag_EqRhs* G4MagHelicalStepper::fPtrMagEqOfMot = nullptr
privateinherited

Definition at line 116 of file G4MagHelicalStepper.hh.

Referenced by G4MagHelicalStepper::AdvanceHelix().

◆ frCurve

G4double G4MagHelicalStepper::frCurve = 0.0
privateinherited

Definition at line 121 of file G4MagHelicalStepper.hh.

◆ frHelix

G4double G4MagHelicalStepper::frHelix = 0.0
privateinherited

Definition at line 122 of file G4MagHelicalStepper.hh.

◆ fUnitConstant

const G4double G4MagHelicalStepper::fUnitConstant = 0.299792458*(GeV/(tesla*m))
staticprivateinherited

Definition at line 113 of file G4MagHelicalStepper.hh.

Referenced by G4MagHelicalStepper::AdvanceHelix().

◆ yFinal

G4ThreeVector G4MagHelicalStepper::yFinal
privateinherited

Definition at line 123 of file G4MagHelicalStepper.hh.

◆ yInitial

G4ThreeVector G4MagHelicalStepper::yInitial
privateinherited

Definition at line 123 of file G4MagHelicalStepper.hh.

◆ yMidPoint

G4ThreeVector G4MagHelicalStepper::yMidPoint
privateinherited

Definition at line 123 of file G4MagHelicalStepper.hh.


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