A mask for energy masking. More...

#include <EnergyMask.h>

Public Member Functions
	EnergyMask (double dyde, double dydL, double dydx, double dy, double dL, double dx, double dE)
	Constructor.

double	getStep () const
	Returns energy step size of the discrete mask.

double	getFullWidth () const
	Returns mask full width.

const std::vector< double > &	getMask () const
	Returns discrete mask (note: only half of the mask is stored)

double	getMask (double E) const
	Returns mask value at given energy difference by calling direct calculation of the convolution.

double	getMask (int i) const
	Returns mask value at given index from stored discrete mask.

double	getMask (int i, double fract) const
	Returns mask value with linear interpolation between stored discrete mask elements.

double	getEnergyDifference (int i)
	Returns energy difference w.r.t center of mask.

Static Public Member Functions
static void	setNMin (unsigned Nmin)
	Sets minimal size of discrete mask.

static void	setNMax (unsigned Nmax)
	Sets maximal size of discrete mask.

Private Member Functions
double	twoSquareConvolution (double E) const
	Returns a value of convolution of two square distributions at given photon energy using the largest two of full widths (m_A, m_B).

double	threeSquareConvolution (double E) const
	Returns a value of convolution of three square distributions at given photon energy.

double	mask (int i) const
	Returns mask value at given index from stored discrete mask.

Private Attributes
double	m_dE = 0
	energy step

double	m_Wy = 0
	enegy full width of dy

double	m_A = 0
	the largest energy full width

double	m_B = 0
	the middle energy full width

double	m_C = 0
	the smallset energy full width

std::vector< double >	m_mask
	discrete mask (half of)

Static Private Attributes
static unsigned	s_Nmin = 4
	minimal mask size

static unsigned	s_Nmax = 256
	maximal mask size

Detailed Description

A mask for energy masking.

Definition at line 24 of file EnergyMask.h.

Constructor & Destructor Documentation

◆ EnergyMask()

EnergyMask	(	double	dyde,
		double	dydL,
		double	dydx,
		double	dy,
		double	dL,
		double	dx,
		double	dE
	)

Constructor.

Parameters

dyde	derivative dy/de [cm/eV]
dydL	derivative dy/dL
dydx	derivative dy/dx
dy	effective PMT pad size in y [cm]
dL	length of particle trajectory within the quartz [cm]
dx	PMT pad size in x [cm]
dE	energy step [eV]

Definition at line 25 of file EnergyMask.cc.

                                                                                                           :
      m_dE(dE), m_Wy(dy / std::abs(dyde))
    {
      if (dy <= 0) {
        B2ERROR("TOP::EnergyMask: dy must be > 0");
        return;
      }
 
      std::vector<double> x;
      x.push_back(m_Wy);
      x.push_back(std::abs(dL * dydL / dyde));
      x.push_back(std::abs(dx * dydx / dyde));
      std::sort(x.begin(), x.end());
 
      m_A = x[2];
      m_B = x[1];
      m_C = x[0];
 
      unsigned N = (m_A + m_B + m_C) / 2.0 / dE + 1;
      if (N < s_Nmin or N > s_Nmax) return;
 
      if (m_C / m_A > 0.001) {
        for (unsigned i = 0; i <= N; i++) {
          double E = i * dE;
          double p = threeSquareConvolution(E);
          m_mask.push_back(p);
        }
      } else {
        for (unsigned i = 0; i <= N; i++) {
          double E = i * dE;
          double p = twoSquareConvolution(E);
          m_mask.push_back(p);
        }
      }
    }

Member Function Documentation

◆ getEnergyDifference()

double getEnergyDifference ( int i )

inline

Returns energy difference w.r.t center of mask.

Parameters

i	index (all values are valid)

Returns: energy difference w.r.t center of mask [eV]

Definition at line 99 of file EnergyMask.h.

99{return i * m_dE;}

◆ getFullWidth()

double getFullWidth ( ) const

inline

Returns mask full width.

Returns: full width [eV]

Definition at line 62 of file EnergyMask.h.

62{return m_A + m_B + m_C;}

◆ getMask() [1/4]

const std::vector< double > & getMask ( ) const

inline

Returns discrete mask (note: only half of the mask is stored)

Returns: discrete mask

Definition at line 68 of file EnergyMask.h.

68{return m_mask;}

◆ getMask() [2/4]

double getMask ( double E ) const

Returns mask value at given energy difference by calling direct calculation of the convolution.

Parameters

E	photon energy difference w.r.t center of mask [eV]

Returns: mask value

Definition at line 62 of file EnergyMask.cc.

    {
      if (m_C / m_A > 0.001) {
        return threeSquareConvolution(E);
      } else {
        return twoSquareConvolution(E);
      }
    }

◆ getMask() [3/4]

double getMask ( int i ) const

Returns mask value at given index from stored discrete mask.

If discrete mask is empty it calls direct calculation of convolution.

Parameters

i	index (all values are valid)

Returns: mask value

Definition at line 72 of file EnergyMask.cc.

    {
      if (m_mask.empty()) return getMask(i * m_dE);
      return mask(i);
    }

◆ getMask() [4/4]

double getMask	(	int	i,
		double	fract
	)		const

Returns mask value with linear interpolation between stored discrete mask elements.

If discrete mask is empty it calls direct calculation of convolution.

Parameters

i	index (all values are valid)
fract	fractional part for linear interpolation (values btw. -0.5 and 0.5)

Returns: mask value

Definition at line 79 of file EnergyMask.cc.

    {
      if (m_mask.empty()) return getMask((i + fract) * m_dE);
 
      if (fract < 0) {
        i--;
        fract += 1;
      }
      return mask(i) * (1 - fract) + mask(i + 1) * fract;
    }

◆ getStep()

double getStep ( ) const

inline

Returns energy step size of the discrete mask.

Returns: step [eV]

Definition at line 56 of file EnergyMask.h.

56{return m_dE;}

◆ mask()

double mask ( int i ) const

inlineprivate

Returns mask value at given index from stored discrete mask.

Parameters

i	index (all values are valid)

Returns: mask value or 0 if index is out of array range

Definition at line 138 of file EnergyMask.h.

    {
      unsigned k = std::abs(i);
      if (k < m_mask.size()) return m_mask[k];
      return 0;
    }

◆ setNMax()

static void setNMax ( unsigned Nmax )

inlinestatic

Sets maximal size of discrete mask.

Parameters

Nmax	maximal size

Definition at line 50 of file EnergyMask.h.

50{s_Nmax = Nmax;}

◆ setNMin()

static void setNMin ( unsigned Nmin )

inlinestatic

Sets minimal size of discrete mask.

Parameters

Nmin	minimal size

Definition at line 44 of file EnergyMask.h.

44{s_Nmin = Nmin;}

Belle2::TOP::EnergyMask::s_Nmin

static unsigned s_Nmin

minimal mask size

Definition: EnergyMask.h:132

◆ threeSquareConvolution()

double threeSquareConvolution ( double E ) const

private

Returns a value of convolution of three square distributions at given photon energy.

Parameters

E	photon energy difference w.r.t center of mask [eV]

Returns: convolution value

Definition at line 107 of file EnergyMask.cc.

    {
      double halfWid = (m_A + m_B + m_C) / 2;
      if (std::abs(E) >= halfWid) return 0;
 
      double t1 = halfWid - E;
      double t2 = halfWid + E;
      double p = t1 * t1 + t2 * t2;
 
      double t3 = t1 - m_A;
      double t4 = t2 - m_A;
      p -= copysign(t3 * t3, t3) + copysign(t4 * t4, t4);
 
      t3 = t1 - m_B;
      t4 = t2 - m_B;
      p -= copysign(t3 * t3, t3) + copysign(t4 * t4, t4);
 
      t3 = t1 - m_C;
      t4 = t2 - m_C;
      p -= copysign(t3 * t3, t3) + copysign(t4 * t4, t4);
 
      return p / (4 * m_A * m_B * m_C) * m_Wy;
    }

◆ twoSquareConvolution()

double twoSquareConvolution ( double E ) const

private

Returns a value of convolution of two square distributions at given photon energy using the largest two of full widths (m_A, m_B).

Parameters

E	photon energy difference w.r.t center of mask [eV]

Returns: convolution value

Definition at line 91 of file EnergyMask.cc.

    {
      double x1 = (m_A - m_B) / 2;
      double x2 = (m_A + m_B) / 2;
      double x = std::abs(E);
 
      if (x < x1) {
        return 1 / m_A * m_Wy;
      } else if (x < x2) {
        return (x2 - x) / (x2 - x1) / m_A * m_Wy;
      } else {
        return 0;
      }
    }

Member Data Documentation

◆ m_A

double m_A = 0

private

the largest energy full width

Definition at line 127 of file EnergyMask.h.

◆ m_B

double m_B = 0

private

the middle energy full width

Definition at line 128 of file EnergyMask.h.

◆ m_C

double m_C = 0

private

the smallset energy full width

Definition at line 129 of file EnergyMask.h.

◆ m_dE

double m_dE = 0

private

energy step

Definition at line 125 of file EnergyMask.h.

◆ m_mask

std::vector<double> m_mask

private

discrete mask (half of)

Definition at line 130 of file EnergyMask.h.

◆ m_Wy

double m_Wy = 0

private

enegy full width of dy

Definition at line 126 of file EnergyMask.h.

◆ s_Nmax

unsigned s_Nmax = 256

staticprivate

maximal mask size

Definition at line 133 of file EnergyMask.h.

◆ s_Nmin

unsigned s_Nmin = 4

staticprivate

minimal mask size

Definition at line 132 of file EnergyMask.h.

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

top/reconstruction_cpp/include/EnergyMask.h
top/reconstruction_cpp/src/EnergyMask.cc

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ EnergyMask()

Member Function Documentation

◆ getEnergyDifference()

◆ getFullWidth()

◆ getMask() [1/4]

◆ getMask() [2/4]

◆ getMask() [3/4]

◆ getMask() [4/4]

◆ getStep()

◆ mask()

◆ setNMax()

◆ setNMin()

◆ threeSquareConvolution()

◆ twoSquareConvolution()

Member Data Documentation

◆ m_A

◆ m_B

◆ m_C

◆ m_dE

◆ m_mask

◆ m_Wy

◆ s_Nmax

◆ s_Nmin