Utility for expanding the PDF in y direction. More...

#include <YScanner.h>

Inheritance diagram for YScanner:

Collaboration diagram for YScanner:

[legend]

Classes
struct	Derivatives
	Derivatives. More...

struct	PixelProjection
	Down-stream projection of a pixel to prism entrance window w/ a clip on bar exit thickness. More...

struct	Result
	Single PDF peak data. More...

struct	Table
	A table of equidistant entries. More...

struct	TableEntry
	Table entry. More...

Public Types
enum	EGeometry { c_Unified = 0 , c_Segmented = 1 }
	Treatement of quartz geometry. More...

enum	EOptics { c_SemiLinear = 0 , c_Exact = 1 }
	Treatement of spherical mirror optics. More...

Public Member Functions
	YScanner (int moduleID, unsigned N=64)
	Class constructor. More...

void	clear () const
	Clear mutable variables.

void	prepare (double momentum, double beta, double length) const
	Prepare for the PDF expansion in y for a given track mass hypothesis. More...

bool	isAboveThreshold () const
	Returns above Cerenkov threshold flag which is set in the prepare method. More...

void	expand (unsigned col, double yB, double dydz, const Derivatives &D, bool doScan) const
	Performs the PDF expansion in y for a given pixel column using scan or merge methods. More...

const PixelPositions &	getPixelPositions () const
	Returns pixel positions and their sizes. More...

const PixelMasks &	getPixelMasks () const
	Returns pixel masks. More...

const PixelEfficiencies &	getPixelEfficiencies () const
	Returns pixel relative efficiencies. More...

const Table &	getEfficiencies () const
	Returns nominal photon detection efficiencies (PDE) More...

double	getCosTotal () const
	Returns cosine of total reflection angle. More...

double	getMomentum () const
	Returns particle momentum. More...

double	getBeta () const
	Returns particle beta. More...

double	getTrackLengthInQuartz () const
	Returns particle trajectory lenght inside quartz. More...

double	getNumPhotonsPerLen () const
	Returns number of photons per Cerenkov azimuthal angle per track length. More...

double	getNumPhotons () const
	Returns number of photons per Cerenkov azimuthal angle. More...

double	getMeanEnergy () const
	Returns mean photon energy. More...

double	getRMSEnergy () const
	Returns r.m.s of photon energy. More...

double	getMeanEnergyBeta1 () const
	Returns mean photon energy for beta = 1. More...

double	getRMSEnergyBeta1 () const
	Returns r.m.s of photon energy for beta = 1. More...

double	getSigmaScattering () const
	Returns r.m.s of multiple scattering angle in quartz converted to photon energy. More...

const Table &	getEnergyDistribution () const
	Returns photon energy distribution. More...

const Table &	getQuasyEnergyDistribution () const
	Returns photon energy distribution convoluted with multiple scattering. More...

const std::vector< Result > &	getResults () const
	Returns the results of PDF expansion in y. More...

bool	isScanDone () const
	Checks which expansion method was used. More...

int	getModuleID () const
	Returns slot ID. More...

EGeometry	getGeometry () const
	Returns quartz geometry treatement. More...

EOptics	getOptics () const
	Returns treatement of spherical mirror optics. More...

const std::vector< BarSegment > &	getBars () const
	Returns geometry data of bar segments. More...

const Mirror &	getMirror () const
	Returns geometry data of spherical mirror. More...

const Prism &	getPrism () const
	Returns geometry data of prism. More...

Static Public Member Functions
static void	setScanLimits (int maxReflections)
	Sets parameters for selection between expand methods. More...

Protected Attributes
int	m_moduleID = 0
	slot ID

EGeometry	m_geometry = c_Unified
	quartz geometry

EOptics	m_optics = c_SemiLinear
	spherical mirror optics

std::vector< BarSegment >	m_bars
	geometry data of bar segments

Mirror	m_mirror
	spherical mirror geometry data

Prism	m_prism
	prism geometry data

Private Member Functions
double	setEnergyDistribution (double beta) const
	Sets photon energy distribution and mean photon energy according to nominal PDE and particle beta. More...

void	integrate (const EnergyMask *energyMask, double Ecp, Result &result) const
	Integrates quasy energy distribution multiplied with energy mask. More...

double	prismEntranceY (double y, int k, double dydz) const
	Calculates y at prism entrance from detection position, reflection number and photon slope. More...

void	projectPixel (double yc, double size, int k, double dydz, PixelProjection &proj) const
	Calculates a projection of a pixel to prism entrance window (going down-stream the photon). More...

void	scan (unsigned col, double yB, double dydz, const Derivatives &D, int j1, int j2) const
	Performs expansion w/ the scan over reflections. More...

void	merge (unsigned col, double dydz, int j1, int j2) const
	Performs expansion by merging all reflections. More...

PixelMasks &	pixelMasks ()
	Returns non-const pixel masks. More...

PixelEfficiencies &	pixelEfficiencies ()
	Returns non-const pixel relative efficiencies. More...

Private Attributes
PixelPositions	m_pixelPositions
	positions and sizes of pixels

PixelMasks	m_pixelMasks
	pixel masks

PixelEfficiencies	m_pixelEfficiencies
	pixel relative efficiencies

Table	m_efficiency
	nominal photon detection efficiencies (PDE)

double	m_meanE0 = 0
	mean photon energy for beta = 1

double	m_rmsE0 = 0
	r.m.s of photon energy for beta = 1

double	m_cosTotal = 0
	cosine of total reflection angle

double	m_momentum = 0
	particle momentum magnitude

double	m_beta = 0
	particle beta

double	m_length = 0
	length of particle trajectory inside quartz

double	m_numPhotons = 0
	number of photons per Cerenkov azimuthal angle per track length

double	m_meanE = 0
	mean photon energy

double	m_rmsE = 0
	r.m.s of photon energy

double	m_sigmaScat = 0
	r.m.s. More...

Table	m_energyDistribution
	photon energy distribution

Table	m_quasyEnergyDistribution
	photon energy distribution convoluted with multiple scattering

bool	m_aboveThreshold = false
	true if beta is above the Cerenkov threshold

std::vector< Result >	m_results
	results of PDF expansion in y

bool	m_scanDone = false
	true if scan performed, false if reflections just merged

Static Private Attributes
static int	s_maxReflections = 16
	maximal number of reflections to perform scan

Friends
class	TOPRecoManager

Detailed Description

Utility for expanding the PDF in y direction.

Definition at line 31 of file YScanner.h.

Member Enumeration Documentation

◆ EGeometry

enum EGeometry

inherited

Treatement of quartz geometry.

Enumerator
c_Unified	single bar with average width and thickness
c_Segmented	segmented bars

Definition at line 33 of file RaytracerBase.h.

◆ EOptics

enum EOptics

inherited

Treatement of spherical mirror optics.

Enumerator
c_SemiLinear	semi-linear approximation
c_Exact	exact optics

Definition at line 41 of file RaytracerBase.h.

Constructor & Destructor Documentation

◆ YScanner()

YScanner	(	int	moduleID,
		unsigned	N = `64`
	)

explicit

Class constructor.

Sets pixel positions of a given module and nominal photon detection efficiency.

Parameters

moduleID	slot ID
N	size of nominal photon detection efficiency table

Definition at line 52 of file YScanner.cc.

                                               : RaytracerBase(moduleID, c_Unified, c_SemiLinear),
       m_pixelPositions(PixelPositions(moduleID)),
       m_pixelMasks(PixelMasks(moduleID)),
       m_pixelEfficiencies(PixelEfficiencies(moduleID))
     {
       if (N < 2) {
         B2FATAL("TOP::YScanner: N must be > 1");
         return;
       }
  
       // set the table of nominal photon detection efficiencies (incl. wavelength filter)
  
       const auto* topgp = TOPGeometryPar::Instance();
       const auto* geo = topgp->getGeometry();
       auto qe = geo->getNominalQE(); // get a copy
       qe.applyFilterTransmission(geo->getWavelengthFilter());
  
       double minE = TOPGeometryPar::c_hc / qe.getMaxLambda();
       double maxE = TOPGeometryPar::c_hc / qe.getMinLambda();
       if (minE >= maxE) {
         B2FATAL("TOP::YScanner: quantum efficiency found zero for all wavelengths");
         return;
       }
       m_efficiency.set(minE, (maxE - minE) / (N - 1));
  
       const auto& tdc = geo->getNominalTDC();
       for (unsigned i = 0; i < N; i++) {
         double e = m_efficiency.getX(i);
         double lambda = TOPGeometryPar::c_hc / e;
         double effi = qe.getEfficiency(lambda) * tdc.getEfficiency();
         m_efficiency.entries.push_back(TableEntry(effi, e, e * e));
       }
  
       // set cosine of total reflection angle using photon mean energy for beta = 1
  
       double s = 0;
       double se = 0;
       double see = 0;
       for (const auto& entry : m_efficiency.entries) {
         double e = entry.x;
         double p = entry.y * (1 - 1 / pow(topgp->getPhaseIndex(e), 2));
         s += p;
         se += p * e;
         see += p * e * e;
       }
       if (s == 0) return;
       m_meanE0 = se / s;
       m_rmsE0 = sqrt(see / s - m_meanE0 * m_meanE0);
       m_cosTotal = sqrt(1 - 1 / pow(topgp->getPhaseIndex(m_meanE0), 2));
     }

Member Function Documentation

◆ expand()

void expand	(	unsigned	col,
		double	yB,
		double	dydz,
		const Derivatives &	D,
		bool	doScan
	)		const

Performs the PDF expansion in y for a given pixel column using scan or merge methods.

Results accessable with getResults() method.

Parameters

col	pixel column number (0-based)
yB	unfolded coordinate y of photon at prism entrance (= Bar exit) plane
dydz	photon slope in y-z projection at prism entrance (dy/dz)
D	the derivatives
doScan	if true decide between scan and merge methods, if false always use merge method

Definition at line 217 of file YScanner.cc.

◆ getBars()

const std::vector<BarSegment>& getBars ( ) const

inlineinherited

Returns geometry data of bar segments.

Returns: geometry data of bar segments

Definition at line 160 of file RaytracerBase.h.

◆ getBeta()

double getBeta ( ) const

inline

Returns particle beta.

Returns: particle beta

Definition at line 313 of file YScanner.h.

313 {return m_beta;}

Belle2::TOP::YScanner::m_beta

double m_beta

particle beta

Definition: YScanner.h:467

◆ getCosTotal()

double getCosTotal ( ) const

inline

Returns cosine of total reflection angle.

Returns: cosine of total reflection angle at mean photon energy for beta = 1

Definition at line 301 of file YScanner.h.

◆ getEfficiencies()

const Table& getEfficiencies ( ) const

inline

Returns nominal photon detection efficiencies (PDE)

Returns: nominal photon detection efficiencies

Definition at line 295 of file YScanner.h.

◆ getEnergyDistribution()

const Table& getEnergyDistribution ( ) const

inline

Returns photon energy distribution.

Returns: photon energy distribution

Definition at line 367 of file YScanner.h.

◆ getGeometry()

EGeometry getGeometry ( ) const

inlineinherited

Returns quartz geometry treatement.

Returns: quartz geometry treatement

Definition at line 148 of file RaytracerBase.h.

◆ getMeanEnergy()

double getMeanEnergy ( ) const

inline

Returns mean photon energy.

Returns: mean photon energy

Definition at line 337 of file YScanner.h.

◆ getMeanEnergyBeta1()

double getMeanEnergyBeta1 ( ) const

inline

Returns mean photon energy for beta = 1.

Returns: mean photon energy for beta = 1

Definition at line 349 of file YScanner.h.

◆ getMirror()

const Mirror& getMirror ( ) const

inlineinherited

Returns geometry data of spherical mirror.

Returns: geometry data of spherical mirror

Definition at line 166 of file RaytracerBase.h.

◆ getModuleID()

int getModuleID ( ) const

inlineinherited

Returns slot ID.

Returns: slot ID

Definition at line 142 of file RaytracerBase.h.

◆ getMomentum()

double getMomentum ( ) const

inline

Returns particle momentum.

Returns: particle momentum

Definition at line 307 of file YScanner.h.

◆ getNumPhotons()

double getNumPhotons ( ) const

inline

Returns number of photons per Cerenkov azimuthal angle.

Returns: number of photons per radian

Definition at line 331 of file YScanner.h.

◆ getNumPhotonsPerLen()

double getNumPhotonsPerLen ( ) const

inline

Returns number of photons per Cerenkov azimuthal angle per track length.

Returns: number of photons per radian per centimeter

Definition at line 325 of file YScanner.h.

◆ getOptics()

EOptics getOptics ( ) const

inlineinherited

Returns treatement of spherical mirror optics.

Returns: spherical mirror optics

Definition at line 154 of file RaytracerBase.h.

◆ getPixelEfficiencies()

const PixelEfficiencies& getPixelEfficiencies ( ) const

inline

Returns pixel relative efficiencies.

Returns: pixel relative efficiencies

Definition at line 289 of file YScanner.h.

◆ getPixelMasks()

const PixelMasks& getPixelMasks ( ) const

inline

Returns pixel masks.

Returns: pixel masks

Definition at line 283 of file YScanner.h.

◆ getPixelPositions()

const PixelPositions& getPixelPositions ( ) const

inline

Returns pixel positions and their sizes.

Returns: pixel positions and their sizes in module local frame

Definition at line 277 of file YScanner.h.

◆ getPrism()

const Prism& getPrism ( ) const

inlineinherited

Returns geometry data of prism.

Returns: geometry data of prism

Definition at line 172 of file RaytracerBase.h.

◆ getQuasyEnergyDistribution()

const Table& getQuasyEnergyDistribution ( ) const

inline

Returns photon energy distribution convoluted with multiple scattering.

Returns: photon energy distribution convoluted with multiple scattering

Definition at line 373 of file YScanner.h.

◆ getResults()

const std::vector<Result>& getResults ( ) const

inline

Returns the results of PDF expansion in y.

Returns: results

Definition at line 379 of file YScanner.h.

◆ getRMSEnergy()

double getRMSEnergy ( ) const

inline

Returns r.m.s of photon energy.

Returns: r.m.s of photon energy

Definition at line 343 of file YScanner.h.

◆ getRMSEnergyBeta1()

double getRMSEnergyBeta1 ( ) const

inline

Returns r.m.s of photon energy for beta = 1.

Returns: r.m.s of photon energy for beta = 1

Definition at line 355 of file YScanner.h.

◆ getSigmaScattering()

double getSigmaScattering ( ) const

inline

Returns r.m.s of multiple scattering angle in quartz converted to photon energy.

Returns: r.m.s of multiple scattering angle in quartz [eV]

Definition at line 361 of file YScanner.h.

◆ getTrackLengthInQuartz()

double getTrackLengthInQuartz ( ) const

inline

Returns particle trajectory lenght inside quartz.

Returns: particle trajectory lenght inside quartz

Definition at line 319 of file YScanner.h.

◆ integrate()

void integrate	(	const EnergyMask *	energyMask,
		double	Ecp,
		Result &	result
	)		const

private

Integrates quasy energy distribution multiplied with energy mask.

Parameters

energyMask	energy mask (pointer must be valid)
Ecp	position of the mask
result	updated result [in/out]

Definition at line 346 of file YScanner.cc.

◆ isAboveThreshold()

bool isAboveThreshold ( ) const

inline

Returns above Cerenkov threshold flag which is set in the prepare method.

Returns: true, if beta is above the Cherenkov threshold for at least one PDE data point

Definition at line 260 of file YScanner.h.

◆ isScanDone()

bool isScanDone ( ) const

inline

Checks which expansion method was used.

Returns: true if scan, false if merge

Definition at line 385 of file YScanner.h.

◆ merge()

void merge	(	unsigned	col,
		double	dydz,
		int	j1,
		int	j2
	)		const

private

Performs expansion by merging all reflections.

Parameters

col	pixel column number (0-based)
dydz	photon slope in y-z projection at prism entrance (dy/dz)
j1	first reflection number in y
j2	last (exclusive) reflection number in y

Definition at line 314 of file YScanner.cc.

◆ pixelEfficiencies()

PixelEfficiencies& pixelEfficiencies ( )

inlineprivate

Returns non-const pixel relative efficiencies.

Returns: pixel relative efficiencies

Definition at line 454 of file YScanner.h.

◆ pixelMasks()

PixelMasks& pixelMasks ( )

inlineprivate

Returns non-const pixel masks.

Returns: pixel masks

Definition at line 448 of file YScanner.h.

◆ prepare()

void prepare	(	double	momentum,
		double	beta,
		double	length
	)		const

Prepare for the PDF expansion in y for a given track mass hypothesis.

Sets photon energy and quasy-energy distributions, mean and r.m.s of photon energy, number of photons and aboveThreshold flag.

Parameters

momentum	particle momentum
beta	particle beta
length	length of particle trajectory within the quartz

Definition at line 121 of file YScanner.cc.

◆ prismEntranceY()

double prismEntranceY	(	double	y,
		int	k,
		double	dydz
	)		const

private

Calculates y at prism entrance from detection position, reflection number and photon slope.

Parameters

y	detection position in y
k	valid index of vector of unfolded prism exit windows
dydz	photon slope at prism entrance

Returns: y position at prism entrance

Definition at line 387 of file YScanner.cc.

◆ projectPixel()

void projectPixel	(	double	yc,
		double	size,
		int	k,
		double	dydz,
		PixelProjection &	proj
	)		const

private

Calculates a projection of a pixel to prism entrance window (going down-stream the photon).

Parameters

yc	pixel center in y
size	pixel size in y
k	valid index of vector of unfolded prism exit windows
dydz	photon slope at prism entrance
proj	projection of a pixel to prism entrance [out]

Definition at line 397 of file YScanner.cc.

◆ scan()

void scan	(	unsigned	col,
		double	yB,
		double	dydz,
		const Derivatives &	D,
		int	j1,
		int	j2
	)		const

private

Performs expansion w/ the scan over reflections.

Parameters

col	pixel column number (0-based)
yB	unfolded coordinate y of photon at prism entrance (= Bar exit) plane
dydz	photon slope in y-z projection at prism entrance (dy/dz)
D	the derivatives
j1	first reflection number in y
j2	last (exclusive) reflection number in y

Definition at line 250 of file YScanner.cc.

◆ setEnergyDistribution()

double setEnergyDistribution ( double beta ) const

private

Sets photon energy distribution and mean photon energy according to nominal PDE and particle beta.

Parameters

beta	particle beta

Returns: integral of distribution before normalization

Definition at line 188 of file YScanner.cc.

◆ setScanLimits()

static void setScanLimits ( int maxReflections )

inlinestatic

Sets parameters for selection between expand methods.

Parameters

maxReflections maximal number of reflections in y to perform scan

Definition at line 236 of file YScanner.h.

Member Data Documentation

◆ m_sigmaScat

double m_sigmaScat = 0

mutableprivate

r.m.s.

of multiple scattering angle in photon energy units

Definition at line 472 of file YScanner.h.

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

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

Classes

Public Types

Public Member Functions

Static Public Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Static Private Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ EGeometry

◆ EOptics

Constructor & Destructor Documentation

◆ YScanner()

Member Function Documentation

◆ expand()

◆ getBars()

◆ getBeta()

◆ getCosTotal()

◆ getEfficiencies()

◆ getEnergyDistribution()

◆ getGeometry()

◆ getMeanEnergy()

◆ getMeanEnergyBeta1()

◆ getMirror()

◆ getModuleID()

◆ getMomentum()

◆ getNumPhotons()

◆ getNumPhotonsPerLen()

◆ getOptics()

◆ getPixelEfficiencies()

◆ getPixelMasks()

◆ getPixelPositions()

◆ getPrism()

◆ getQuasyEnergyDistribution()

◆ getResults()

◆ getRMSEnergy()

◆ getRMSEnergyBeta1()

◆ getSigmaScattering()

◆ getTrackLengthInQuartz()

◆ integrate()

◆ isAboveThreshold()

◆ isScanDone()

◆ merge()

◆ pixelEfficiencies()

◆ pixelMasks()

◆ prepare()

◆ prismEntranceY()

◆ projectPixel()

◆ scan()

◆ setEnergyDistribution()

◆ setScanLimits()

Member Data Documentation

◆ m_sigmaScat