The Bfieldcomponentklm1 class. More...

#include <BFieldComponentKlm1.h>

Inheritance diagram for BFieldComponentKlm1:

Classes
struct	BFieldPoint
	Trivial struct representing rz coordinate. More...

Public Member Functions
	BFieldComponentKlm1 ()=default
	The BFieldComponentklm1 constructor.

virtual	~BFieldComponentKlm1 ()=default
	The BFieldComponentklm1 destructor.

virtual void	initialize () override
	Initializes the magnetic field Component.

virtual ROOT::Math::XYZVector	calculate (const ROOT::Math::XYZVector &point) const override
	Calculates the magnetic field vector at the specified space point.

virtual void	terminate () override
	Terminates the magnetic field Component.

void	setMapFilename (const std::string &filename)
	Sets the filename of the magnetic field map.

void	setNLayers (int b, int e)
	Sets the number of barrel and endcap layers.

void	setBarrelRegion (double minR, double maxZ, double offset)
	Sets the dimensions of the barrel region.

void	setEndcapRegion (double minR, double minZ)
	Set the dimensions of the endcap region.

void	setLayerParam (double bgapl0, double bironth, double egap, double dl)
	Set the layer parameters.

Private Attributes
double	m_cospi8 {cos(M_PI / 8)}
	cos(pi/8)

double	m_cos3pi8 {cos(3 * M_PI / 8)}
	cos(3pi/8)

double	m_cospi4 {cos(M_PI / 4)}
	cos(pi/4)

std::string	m_mapFilename {""}
	The filename of the magnetic field map.

double	m_mapOffset {0}
	Offset required because the accelerator group defines the Belle center as zero.

double	m_barrelRMin {0}
	The minimum boundaries of BKLM region in r.

double	m_barrelZMax {0}
	The maximum boundaries of BKLM region in r.

double	m_endcapRMin {0}
	The minimum boundaries of EKLM region in r.

double	m_endcapZMin {0}
	The minimum boundaries of EKLM region in z.

int	m_nBarrelLayers {0}
	The number of layers per 1 sector for BKLM.

int	m_nEndcapLayers {0}
	The number of layers per 1 sector for EKLM.

double	m_barrelGapHeightLayer0 {0}
	Gap height of BKLM layer0.

double	m_endcapGapHeight {0}
	Gap height of BKLM layer1-14.

double	m_dLayer {0}
	depth of BKLM module?

double	m_barrelIronThickness {0}
	Thickness of Barrel iron plate.

double	m_barrelZBreakpoint [15] {0}
	z position of breakpoints between the two linear approximations of Bz in the barrel.

double	m_barrelRBreakpoint [15] {0}
	z position of breakpoints between the two linear approximations of Br in the barrel.

double	m_barrelFieldZSlope1 [15] {0}
	Slope of Bz before the breakpoint in the barrel.

double	m_barrelFieldZIntercept1 [15] {0}
	Intercept of Bz before the beackpoint in the barrel.

double	m_barrelFieldZSlope2 [15] {0}
	Slope of Bz after the breakpoint in the barrel.

double	m_barrelFieldZIntercept2 [15] {0}
	Intercept of Bz after the breakpoint in the barrel.

double	m_barrelFieldRSlope1 [15] {0}
	Slope of Br before the breakpoint in the barrel.

double	m_barrelFieldRIntercept1 [15] {0}
	Intercept of Br before the beackpoint in the barrel.

double	m_barrelFieldRSlope2 [15] {0}
	Slope of Br after the breakpoint in the barrel.

double	m_barrelFieldRIntercept2 [15] {0}
	Intercept of Br after the beackpoint in the barrel.

double	m_endcapZBreakpoint [2][15][5] {{{0}}}
	z position of breakpoints between linear functions in the endcap.

double	m_endcapRBreakpoint [2][15][5] {{{0}}}
	r position of breakpoints between linear functions in the endcap First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

double	m_endcapFieldZSlope [2][15][5] {{{0}}}
	Slopes of the linear approximation of Bz in the endcap.

double	m_endcapFieldZIntercept [2][15][5] {{{0}}}
	Intercepts of the linear approximation of Bz in the endcap.

double	m_endcapFieldRSlope [2][15][5] {{{0}}}
	Slopes of the linear approximation of Br in the endcap.

double	m_endcapFieldRIntercept [2][15][5] {{{0}}}
	Intercepts of the linear approximation of Br in the endcap.

Detailed Description

The Bfieldcomponentklm1 class.

This class represents a magnetic field map in KLM region and outside of solenoid. This magnetic field is for Belle. This is porting class from g4superb to basf2. The magnetic field map is stored as linear functions in cylindrical coordinates. It is defined by a maximum radius, a minimum z, r and z, the number of layers for Barrel KLM and Endcap KLM. The ZOffset is used to account for the fact that the acceleration group defines 0 to be in the center of the detector, while the detector group defines the IP to be the center.

Definition at line 33 of file BFieldComponentKlm1.h.

Member Function Documentation

◆ calculate()

ROOT::Math::XYZVector calculate ( const ROOT::Math::XYZVector & point ) const

overridevirtual

Calculates the magnetic field vector at the specified space point.

Parameters

point The space point in Cartesian coordinates (x,y,z) in [cm] at which the magnetic field vector should be calculated.

Returns: The magnetic field vector at the given space point in [T]. Returns a zero vector XYZVector(0,0,0) if the space point lies outside the region described by the Component.

Implements BFieldComponentAbs.

Definition at line 87 of file BFieldComponentKlm1.cc.

{
  //Get the r and z Component
  double r = point.Rho();
  double x = point.X();
  double y = point.Y();
  double z = point.Z() - m_mapOffset;
  double absZ =  std::abs(z);
 
  ROOT::Math::XYZVector bField(0., 0., 0.);
 
  // Barrel
  if (absZ < m_barrelZMax) {
 
    // This code assumes that we are in the barrel KLM.  Use the field map
    // inside an iron plate; use zero in the gap between the iron plates.
 
    double cosphi = std::abs(x) / r;
    double d = ((cosphi < m_cospi8) ? ((cosphi < m_cos3pi8) ? std::abs(y)
                                       : (std::abs(x) + std::abs(y)) * m_cospi4)
                : std::abs(x)) - m_barrelRMin - m_barrelGapHeightLayer0;
 
    if (d >= 0.0) {
      int layer = static_cast<int>(floor(d / m_dLayer));
 
      // make sure layer is in a valid range
      if (layer < 0 || layer > m_nBarrelLayers) return bField;
      if (layer == m_nBarrelLayers) {
        layer = m_nBarrelLayers - 1;
        d = layer * m_dLayer; // for extra-thick outermost iron plate
      }
      if ((d - layer * m_dLayer) < m_barrelIronThickness) {
        double br = ((absZ > m_barrelRBreakpoint[layer]) ?
                     m_barrelFieldRIntercept2[layer] + m_barrelFieldRSlope2[layer] * absZ :
                     m_barrelFieldRIntercept1[layer] + m_barrelFieldRSlope1[layer] * absZ);
        if (z < 0.0) { br = -br; }
        bField.SetXYZ(br * x / r, br * y / r,
                      ((absZ > m_barrelZBreakpoint[layer]) ?
                       m_barrelFieldZIntercept2[layer] + m_barrelFieldZSlope2[layer] * absZ :
                       m_barrelFieldZIntercept1[layer] + m_barrelFieldZSlope1[layer] * absZ));
      }
    }
  } else if (absZ > m_endcapZMin) {
    //Endcap
    if (r <= m_endcapRMin) return bField;
 
    // This code assumes that we are in the endcap KLM.
    // The field in an inter-plate gap in the endcap is not zero.
 
    double dz = absZ - (m_endcapZMin - m_endcapGapHeight);
    int layer = static_cast<int>(floor(dz / m_dLayer));
    // make sure layer is in a valid range
    if (layer < 0 || layer >= m_nEndcapLayers) return bField;
 
    int GapIron = 0;      // in gap
    if ((dz - m_dLayer * layer) > m_endcapGapHeight) GapIron = 1;      // in Iron plate?
    for (int j = 0; j < 5; j++) {
      if (r < m_endcapRBreakpoint[GapIron][layer][j]) {
        double br = m_endcapFieldRIntercept[GapIron][layer][j] + m_endcapFieldRSlope[GapIron][layer][j] * r;
        if (z < 0.0) { br = -br; }
        bField.SetX(br * x / r);
        bField.SetY(br * y / r);
        break;
      }
    }
    for (int j = 0; j < 5; j++) {
      if (r < m_endcapZBreakpoint[GapIron][layer][j]) {
        bField.SetZ(m_endcapFieldZIntercept[GapIron][layer][j] + m_endcapFieldZSlope[GapIron][layer][j] * r);
        break;
      }
    }
  }
 
  return bField;
}

◆ initialize()

void initialize ( )

overridevirtual

Initializes the magnetic field Component.

This method opens the magnetic field map file.

Reimplemented from BFieldComponentAbs.

Definition at line 23 of file BFieldComponentKlm1.cc.

{
  if (m_mapFilename.empty()) {
    B2ERROR("The filename for the magnetic field Component is empty !");
    return;
  }
 
  string fullPath = FileSystem::findFile("/data/" + m_mapFilename);
 
  if (!FileSystem::fileExists(fullPath)) {
    B2ERROR("The magnetic field map file '" << m_mapFilename << "' could not be found !");
    return;
  }
 
  //Load the map file
  io::filtering_istream fieldMapFile;
  fieldMapFile.push(io::file_source(fullPath));
 
  //read the data from the file
  B2DEBUG(10, "Loading the magnetic field from file '" << m_mapFilename << "' in to the memory...");
 
  char dummy[100];
 
  //store parameters for Barrel
  fieldMapFile.getline(dummy, sizeof(dummy));
  for (int layer = 0; layer < m_nBarrelLayers; ++layer) {
    int l;
    fieldMapFile >> l >> m_barrelZBreakpoint[layer] >> m_barrelRBreakpoint[layer]
                 >> m_barrelFieldZSlope1[layer]
                 >> m_barrelFieldZIntercept1[layer]
                 >> m_barrelFieldZSlope2[layer]
                 >> m_barrelFieldZIntercept2[layer]
                 >> m_barrelFieldRSlope1[layer]
                 >> m_barrelFieldRIntercept1[layer]
                 >> m_barrelFieldRSlope2[layer]
                 >> m_barrelFieldRIntercept2[layer];
 
    if (layer != l)
      B2ERROR("Barrel Parameter file is something wrong ! " << layer << " " << l);
  }
 
  //store parameters for Endcap
  fieldMapFile.getline(dummy, sizeof(dummy));
  fieldMapFile.getline(dummy, sizeof(dummy));
  for (int GapIron = 0; GapIron < 2; GapIron++) {
    for (int layer = 0; layer < m_nEndcapLayers + 1; layer++) {
      for (int j = 0; j < 5; j++) {
        int g, l, jj;
        fieldMapFile >> g >> l >> jj
                     >> m_endcapZBreakpoint[GapIron][layer][j] >> m_endcapRBreakpoint[GapIron][layer][j]
                     >> m_endcapFieldZSlope[GapIron][layer][j]
                     >> m_endcapFieldZIntercept[GapIron][layer][j]
                     >> m_endcapFieldRSlope[GapIron][layer][j]
                     >> m_endcapFieldRIntercept[GapIron][layer][j];
        if (GapIron != g || layer != l || jj != j)
          B2ERROR("Endcap Parameter file is something wrong ! " << g << " " << l << " " << jj);
      }
    }
  }
 
  B2DEBUG(10, "... loaded ");
}

◆ setBarrelRegion()

void setBarrelRegion	(	double	minR,
		double	maxZ,
		double	offset
	)

inline

Sets the dimensions of the barrel region.

Parameters

minR	minimal radius
maxZ	max extension in z in both directions
offset	map offset in z

Definition at line 87 of file BFieldComponentKlm1.h.

87{ m_barrelRMin = minR; m_barrelZMax = maxZ; m_mapOffset = offset; }

◆ setEndcapRegion()

void setEndcapRegion	(	double	minR,
		double	minZ
	)

inline

Set the dimensions of the endcap region.

Parameters

minR	minimal radius
minZ	starting z coordinate in both directions

Definition at line 93 of file BFieldComponentKlm1.h.

93{ m_endcapRMin = minR; m_endcapZMin = minZ;}

◆ setLayerParam()

void setLayerParam	(	double	bgapl0,
		double	bironth,
		double	egap,
		double	dl
	)

inline

Set the layer parameters.

Parameters

bgapl0	Barrel gap height for layer 0.
bironth	Barrel iron thickness.
egap	Endcap gap height.
dl	Distance between two layers.

Definition at line 102 of file BFieldComponentKlm1.h.

    {
      m_barrelGapHeightLayer0 = bgapl0;  m_barrelIronThickness = bironth;
      m_endcapGapHeight = egap; m_dLayer = dl;
    }

◆ setMapFilename()

void setMapFilename ( const std::string & filename )

inline

Sets the filename of the magnetic field map.

Parameters

filename The filename of the magnetic field map.

Definition at line 74 of file BFieldComponentKlm1.h.

74{ m_mapFilename = filename; };

◆ setNLayers()

void setNLayers	(	int	b,
		int	e
	)

inline

Sets the number of barrel and endcap layers.

Parameters

b	barrel layers
e	endcap layers

Definition at line 80 of file BFieldComponentKlm1.h.

80{m_nBarrelLayers = b; m_nEndcapLayers = e;}

◆ terminate()

void terminate ( )

overridevirtual

Terminates the magnetic field Component.

Reimplemented from BFieldComponentAbs.

Definition at line 164 of file BFieldComponentKlm1.cc.

165{

166}

Member Data Documentation

◆ m_barrelFieldRIntercept1

double m_barrelFieldRIntercept1[15] {0}

private

Intercept of Br before the beackpoint in the barrel.

Index indicates the current layer

Definition at line 167 of file BFieldComponentKlm1.h.

◆ m_barrelFieldRIntercept2

double m_barrelFieldRIntercept2[15] {0}

private

Intercept of Br after the beackpoint in the barrel.

Index indicates the current layer

Definition at line 173 of file BFieldComponentKlm1.h.

◆ m_barrelFieldRSlope1

double m_barrelFieldRSlope1[15] {0}

private

Slope of Br before the breakpoint in the barrel.

Index indicates the current layer

Definition at line 164 of file BFieldComponentKlm1.h.

◆ m_barrelFieldRSlope2

double m_barrelFieldRSlope2[15] {0}

private

Slope of Br after the breakpoint in the barrel.

Index indicates the current layer

Definition at line 170 of file BFieldComponentKlm1.h.

◆ m_barrelFieldZIntercept1

double m_barrelFieldZIntercept1[15] {0}

private

Intercept of Bz before the beackpoint in the barrel.

Index indicates the current layer

Definition at line 155 of file BFieldComponentKlm1.h.

◆ m_barrelFieldZIntercept2

double m_barrelFieldZIntercept2[15] {0}

private

Intercept of Bz after the breakpoint in the barrel.

Index indicates the current layer

Definition at line 161 of file BFieldComponentKlm1.h.

◆ m_barrelFieldZSlope1

double m_barrelFieldZSlope1[15] {0}

private

Slope of Bz before the breakpoint in the barrel.

Index indicates the current layer

Definition at line 152 of file BFieldComponentKlm1.h.

◆ m_barrelFieldZSlope2

double m_barrelFieldZSlope2[15] {0}

private

Slope of Bz after the breakpoint in the barrel.

Index indicates the current layer

Definition at line 158 of file BFieldComponentKlm1.h.

◆ m_barrelGapHeightLayer0

double m_barrelGapHeightLayer0 {0}

private

Gap height of BKLM layer0.

Definition at line 136 of file BFieldComponentKlm1.h.

◆ m_barrelIronThickness

double m_barrelIronThickness {0}

private

Thickness of Barrel iron plate.

Definition at line 142 of file BFieldComponentKlm1.h.

◆ m_barrelRBreakpoint

double m_barrelRBreakpoint[15] {0}

private

z position of breakpoints between the two linear approximations of Br in the barrel.

Index indicates the current layer

Definition at line 149 of file BFieldComponentKlm1.h.

◆ m_barrelRMin

double m_barrelRMin {0}

private

The minimum boundaries of BKLM region in r.

Definition at line 122 of file BFieldComponentKlm1.h.

◆ m_barrelZBreakpoint

double m_barrelZBreakpoint[15] {0}

private

z position of breakpoints between the two linear approximations of Bz in the barrel.

Index indicates the current layer

Definition at line 146 of file BFieldComponentKlm1.h.

◆ m_barrelZMax

double m_barrelZMax {0}

private

The maximum boundaries of BKLM region in r.

Definition at line 124 of file BFieldComponentKlm1.h.

◆ m_cos3pi8

double m_cos3pi8 {cos(3 * M_PI / 8)}

private

cos(3pi/8)

Definition at line 112 of file BFieldComponentKlm1.h.

◆ m_cospi4

double m_cospi4 {cos(M_PI / 4)}

private

cos(pi/4)

Definition at line 114 of file BFieldComponentKlm1.h.

◆ m_cospi8

double m_cospi8 {cos(M_PI / 8)}

private

cos(pi/8)

Definition at line 110 of file BFieldComponentKlm1.h.

◆ m_dLayer

double m_dLayer {0}

private

depth of BKLM module?

Definition at line 140 of file BFieldComponentKlm1.h.

◆ m_endcapFieldRIntercept

double m_endcapFieldRIntercept[2][15][5] {{{0}}}

private

Intercepts of the linear approximation of Br in the endcap.

First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 205 of file BFieldComponentKlm1.h.

◆ m_endcapFieldRSlope

double m_endcapFieldRSlope[2][15][5] {{{0}}}

private

Slopes of the linear approximation of Br in the endcap.

First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 200 of file BFieldComponentKlm1.h.

◆ m_endcapFieldZIntercept

double m_endcapFieldZIntercept[2][15][5] {{{0}}}

private

Intercepts of the linear approximation of Bz in the endcap.

First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 195 of file BFieldComponentKlm1.h.

◆ m_endcapFieldZSlope

double m_endcapFieldZSlope[2][15][5] {{{0}}}

private

Slopes of the linear approximation of Bz in the endcap.

First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 190 of file BFieldComponentKlm1.h.

◆ m_endcapGapHeight

double m_endcapGapHeight {0}

private

Gap height of BKLM layer1-14.

Definition at line 138 of file BFieldComponentKlm1.h.

◆ m_endcapRBreakpoint

double m_endcapRBreakpoint[2][15][5] {{{0}}}

private

r position of breakpoints between linear functions in the endcap First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 184 of file BFieldComponentKlm1.h.

◆ m_endcapRMin

double m_endcapRMin {0}

private

The minimum boundaries of EKLM region in r.

Definition at line 126 of file BFieldComponentKlm1.h.

◆ m_endcapZBreakpoint

double m_endcapZBreakpoint[2][15][5] {{{0}}}

private

z position of breakpoints between linear functions in the endcap.

First index indicates whether or not where in a gap (0) or in iron (1), second index is the layer and third index is the number of breaks we have in the linear approximation and their positions

Definition at line 179 of file BFieldComponentKlm1.h.

◆ m_endcapZMin

double m_endcapZMin {0}

private

The minimum boundaries of EKLM region in z.

Definition at line 128 of file BFieldComponentKlm1.h.

◆ m_mapFilename

std::string m_mapFilename {""}

private

The filename of the magnetic field map.

Definition at line 117 of file BFieldComponentKlm1.h.

◆ m_mapOffset

double m_mapOffset {0}

private

Offset required because the accelerator group defines the Belle center as zero.

Definition at line 119 of file BFieldComponentKlm1.h.

◆ m_nBarrelLayers

int m_nBarrelLayers {0}

private

The number of layers per 1 sector for BKLM.

Definition at line 131 of file BFieldComponentKlm1.h.

◆ m_nEndcapLayers

int m_nEndcapLayers {0}

private

The number of layers per 1 sector for EKLM.

Definition at line 133 of file BFieldComponentKlm1.h.

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

geometry/bfieldmap/include/BFieldComponentKlm1.h
geometry/bfieldmap/src/BFieldComponentKlm1.cc

Classes

Public Member Functions

Private Attributes

Detailed Description

Member Function Documentation

◆ calculate()

◆ initialize()

◆ setBarrelRegion()

◆ setEndcapRegion()

◆ setLayerParam()

◆ setMapFilename()

◆ setNLayers()

◆ terminate()

Member Data Documentation

◆ m_barrelFieldRIntercept1

◆ m_barrelFieldRIntercept2

◆ m_barrelFieldRSlope1

◆ m_barrelFieldRSlope2

◆ m_barrelFieldZIntercept1

◆ m_barrelFieldZIntercept2

◆ m_barrelFieldZSlope1

◆ m_barrelFieldZSlope2

◆ m_barrelGapHeightLayer0

◆ m_barrelIronThickness

◆ m_barrelRBreakpoint

◆ m_barrelRMin

◆ m_barrelZBreakpoint

◆ m_barrelZMax

◆ m_cos3pi8

◆ m_cospi4

◆ m_cospi8

◆ m_dLayer

◆ m_endcapFieldRIntercept

◆ m_endcapFieldRSlope

◆ m_endcapFieldZIntercept

◆ m_endcapFieldZSlope

◆ m_endcapGapHeight

◆ m_endcapRBreakpoint

◆ m_endcapRMin

◆ m_endcapZBreakpoint

◆ m_endcapZMin

◆ m_mapFilename

◆ m_mapOffset

◆ m_nBarrelLayers

◆ m_nEndcapLayers