describes the DELPHI magnetic field. The axial symmetry field is mainly directed along Z axis. The function MagneticField(yTrack,B) calculates the magnetic induction vector B in given point corresponding according to parameterisation given in: P.Billoir, DELPHI 87-6 PROG 65, 1987. More...

#include <G4DELPHIMagField.hh>

Inheritance diagram for G4DELPHIMagField:

Public Member Functions
	G4DELPHIMagField ()=default
	~G4DELPHIMagField () override=default
void	GetFieldValue (const G4double yTrack[], G4double B[]) const override
G4Field *	Clone () const override
Public Member Functions inherited from G4MagneticField
	G4MagneticField ()
	~G4MagneticField () override=default
	G4MagneticField (const G4MagneticField &r)
G4MagneticField &	operator= (const G4MagneticField &p)
G4bool	DoesFieldChangeEnergy () const override
void	GetFieldValue (const G4double Point[4], G4double *Bfield) const override=0
G4FieldType	GetFieldType () const override
Public Member Functions inherited from G4Field
	G4Field (G4bool gravityOn=false)
virtual	~G4Field ()=default
	G4Field (const G4Field &p)=default
G4Field &	operator= (const G4Field &p)
G4bool	IsGravityActive () const
void	SetGravityActive (G4bool OnOffFlag)

Additional Inherited Members
Static Public Attributes inherited from G4Field
static constexpr G4int	MAX_NUMBER_OF_COMPONENTS = 24

Detailed Description

describes the DELPHI magnetic field. The axial symmetry field is mainly directed along Z axis. The function MagneticField(yTrack,B) calculates the magnetic induction vector B in given point corresponding according to parameterisation given in: P.Billoir, DELPHI 87-6 PROG 65, 1987.

Definition at line 51 of file G4DELPHIMagField.hh.

Constructor & Destructor Documentation

◆ G4DELPHIMagField()

G4DELPHIMagField::G4DELPHIMagField ( )

default

Default Constructor and Destructor.

Referenced by Clone().

◆ ~G4DELPHIMagField()

G4DELPHIMagField::~G4DELPHIMagField ( )

overridedefault

Member Function Documentation

◆ Clone()

G4Field * G4DELPHIMagField::Clone ( ) const

overridevirtual

Returns a pointer to a new allocated clone of this object.

Reimplemented from G4Field.

Definition at line 37 of file G4DELPHIMagField.cc.

{
   return new G4DELPHIMagField;
}

◆ GetFieldValue()

void G4DELPHIMagField::GetFieldValue	(	const G4double	yTrack[],
		G4double	B[] ) const

override

Returns the field value on the given position 'yTrack'.

Parameters

[in]	yTrack	Time position array.
[out]	B	The returned field array.

Definition at line 44 of file G4DELPHIMagField.cc.

{
   G4int i, n = 8 ;
   G4double a = 0.001 ;   // mm -> m 
   G4double x = a*yTrack[0], y = a*yTrack[1], z = a*yTrack[2] ;
   G4double x2 = x*x, y2 = y*y, z2 = z*z, r2 = x2 + y2 ;
   G4double r4 = r2*r2, z4 = z2*z2, r6 = r4*r2, z6 = z4*z2 ;
   G4double r8 = r4*r4, z8 = z4*z4, r10 = r8*r2, z10 = z8*z2 ;
   G4double rz = z*std::sqrt(r2), r = std::sqrt(r2+a*a) ;
   G4double Br ;
   G4double P[8], Q[8] ; 
   static G4ThreadLocal G4double c[8] =
                          {
                            -9.26e-5, -3.51e-5, 2.94e-6, -1.10e-6, 
                             6.25e-8, -1.77e-8, -6.88e-10, -7.52e-11 
                          } ;
   P[0] = 2*rz ;
   P[1] = 4*rz*(r2 - 4.0*z2/3.0) ;
   P[2] = 6*rz*(r4 - 4*r2*z2 + 1.6*z4) ;
   P[3] = 8*rz*(r6 - 8*r4*z2 + 9.6*r2*z4 - 64.0*z6/35.0) ;
   P[4] = 10*rz*(r8 - 40.0*r6*z2/3.0 + 32*r4*z4
                    - 128.0*r2*z6/7.0 + 128.0*z8/63.0);
   P[5] = 0 ;
   P[6] = 0 ;
   P[7] = 0 ;
   
   Q[0] = r2 - 2*z2 ;
   Q[1] = r4 - 8*r2*z2 + 8.0*z4/3.0 ;
   Q[2] = r6 - 18*r4*z2 + 24*r2*z4 - 3.2*z6 ;
   Q[3] = r8 - 32*r6*z2 + 96*r4*z4 - 51.2*r2*z6 +128.0*z8/35.0 ;
   Q[4] = r10 - 50*r8*z2 + 800.0*r6*z4/3.0 - 320*r4*z6 
          + 640.0*r2*z8/7.0 - 256.0*z10/63.0 ;
   Q[5] = 0 ;
   Q[6] = 0 ;
   Q[7] = 0 ;
   
   Br = 0 ;
   B[2] = 1.2*tesla  ;    //  the principal Bz value of DELPHI detector
   for(i=0; i<n; ++i)
   {
      Br += c[i]*P[i] ;
      B[2] += c[i]*Q[i] ;
   }
   B[0] = Br*x/r ;
   B[1] = Br*y/r ;
   return ;
}

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

Public Member Functions