Abstract Class representing the SVD cluster time. More...

#include <SVDClusterTime.h>

Inheritance diagram for SVDClusterTime:

Public Member Functions
	SVDClusterTime ()
	Constructor to create an empty Cluster Time Object by default returns the calibrated time.

void	setReturnRawClusterTime ()
	set to return the raw cluster time instead of the calibrated one

void	setTriggerBin (const int triggerBin)
	set the trigger bin

virtual void	computeClusterTime (Belle2::SVD::RawCluster &rawCluster, double &time, double &timeError, int &firstFrame)=0
	computes the cluster time, timeError and FirstFrame

virtual	~SVDClusterTime ()
	virtual destructor

void	applyCoG6Time (const Belle2::SVD::RawCluster &rawCluster, double &time, double &timeError, int &firstFrame)
	CoG6 Time Algorithm.

void	applyCoG3Time (const Belle2::SVD::RawCluster &rawCluster, double &time, double &timeError, int &firstFrame)
	CoG3 Time Algorithm.

void	applyELS3Time (const Belle2::SVD::RawCluster &rawCluster, double &time, double &timeError, int &firstFrame)
	ELS3 Time Algorithm.

Protected Attributes
bool	m_returnRawClusterTime = false
	to be used for time calibration

int	m_triggerBin = std::numeric_limits<int>::quiet_NaN()
	trigger bin

DBObjPtr< HardwareClockSettings >	m_hwClock
	Hardware Clocks.

double	m_apvClockPeriod = 1. / m_hwClock->getClockFrequency(Const::EDetector::SVD, "sampling")
	APV clock period.

SVDPulseShapeCalibrations	m_PulseShapeCal
	SVDPulseShaper calibration wrapper.

SVDCoGTimeCalibrations	m_CoG6TimeCal
	CoG6 time calibration wrapper.

SVD3SampleCoGTimeCalibrations	m_CoG3TimeCal
	CoG3 time calibration wrapper.

SVD3SampleELSTimeCalibrations	m_ELS3TimeCal
	ELS3 time calibration wrapper.

Detailed Description

Abstract Class representing the SVD cluster time.

Definition at line 26 of file SVDClusterTime.h.

Constructor & Destructor Documentation

◆ SVDClusterTime()

SVDClusterTime ( )

inline

Constructor to create an empty Cluster Time Object by default returns the calibrated time.

Definition at line 34 of file SVDClusterTime.h.

34{m_returnRawClusterTime = false;};

Belle2::SVD::SVDClusterTime::m_returnRawClusterTime

bool m_returnRawClusterTime

to be used for time calibration

Definition: SVDClusterTime.h:71

◆ ~SVDClusterTime()

virtual ~SVDClusterTime ( )

inlinevirtual

virtual destructor

Definition at line 57 of file SVDClusterTime.h.

57{};

Member Function Documentation

◆ applyCoG3Time()

void applyCoG3Time	(	const Belle2::SVD::RawCluster &	rawCluster,
		double &	time,
		double &	timeError,
		int &	firstFrame
	)

CoG3 Time Algorithm.

Definition at line 78 of file SVDClusterTime.cc.

    {
      //take the MaxSum 3 samples
      SVDMaxSumAlgorithm maxSum = SVDMaxSumAlgorithm(rawCluster.getClsSamples(false));
 
      std::vector<float> selectedSamples = maxSum.getSelectedSamples();
      firstFrame = maxSum.getFirstFrame();
 
 
      auto begin = selectedSamples.begin();
      const auto end = selectedSamples.end();
 
      auto retval = 0., norm = 0.;
      for (auto step = 0.; begin != end; ++begin, step += m_apvClockPeriod) {
        norm += static_cast<double>(*begin);
        retval += static_cast<double>(*begin) * step;
      }
      float rawtime = retval / norm;
 
      if (std::isnan(float(m_triggerBin)))
        B2FATAL("OOPS, we can't continue, you have to set the trigger bin!");
 
      if (m_returnRawClusterTime)
        time = rawtime;
      else
        //cellID = 10 not used for calibration
        time = m_CoG3TimeCal.getCorrectedTime(rawCluster.getSensorID(), rawCluster.isUSide(), 10, rawtime, m_triggerBin);
 
 
 
      // now compute the CoG3 time error
      // assumptions:
      // 1. calibration function parameters error not taken into account
      // 2. 100% correlation among different strip noises
      // 3. error on the sample amplitude = strip noise for all samples
 
      //compute the noise of the clustered sample
      //it is the same for all samples
      //computed assuming 2. (-> linear sum, not quadratic)
      std::vector<Belle2::SVD::StripInRawCluster> strips = rawCluster.getStripsInRawCluster();
      float noise = std::accumulate(strips.begin(), strips.end(), 0., [](float sum, const Belle2::SVD::StripInRawCluster & strip) { return sum + strip.noise; });
 
      //compute the noise of the raw time
      //assuming only the clustered sample amplitude carries an uncertainty
      double rawtimeError = 0;
      begin = selectedSamples.begin();
      for (float i = 0.; begin != end; ++begin, i += 1)
        rawtimeError += TMath::Power((m_apvClockPeriod * i - rawtime) / norm, 2);
      rawtimeError = sqrt(rawtimeError) * noise;
 
      //compute the error on the calibrated time
      timeError = m_CoG3TimeCal.getCorrectedTimeError(rawCluster.getSensorID(), rawCluster.isUSide(), 10, rawtime, rawtimeError,
                                                      m_triggerBin);
    }

◆ applyCoG6Time()

void applyCoG6Time	(	const Belle2::SVD::RawCluster &	rawCluster,
		double &	time,
		double &	timeError,
		int &	firstFrame
	)

CoG6 Time Algorithm.

Definition at line 23 of file SVDClusterTime.cc.

    {
 
      // ISSUES:
      // 1. time error not computed
 
      //the first frame is 0 by definition
      firstFrame = 0;
 
      //take the strips in the rawCluster
      std::vector<Belle2::SVD::StripInRawCluster> strips = rawCluster.getStripsInRawCluster();
 
      //initialize time, stripTime and sumAmplitudes
      time = 0;
      timeError = 0;
      float sumAmplitudes = 0;
 
      for (int i = 0; i < (int)strips.size(); i++) {
 
        Belle2::SVD::StripInRawCluster strip = strips.at(i);
 
        double stripTime = 0;
        float stripSumAmplitudes = 0;
 
        for (int k = 0; k < 6; k ++) {
          stripTime += k * strip.samples[k];
          stripSumAmplitudes += strip.samples[k];
        }
        if (stripSumAmplitudes != 0) {
          stripTime /= (stripSumAmplitudes);
          stripTime *= m_apvClockPeriod;
        } else {
          stripTime = -1;
          B2WARNING("Trying to divide by 0 (ZERO)! Sum of amplitudes is nullptr! Skipping this SVDShaperDigit!");
        }
 
        // correct strip by the CalPeak
        stripTime -= m_PulseShapeCal.getPeakTime(rawCluster.getSensorID(), rawCluster.isUSide(), strip.cellID);
 
        if (std::isnan(float(m_triggerBin)))
          B2FATAL("OOPS, we can't continue, you have to set the trigger bin!");
 
        if (! m_returnRawClusterTime)
          // calibrate strip time (cellID not used)
          stripTime =  m_CoG6TimeCal.getCorrectedTime(rawCluster.getSensorID(), rawCluster.isUSide(), strip.cellID, stripTime, m_triggerBin);
 
        //update cluster time
        time += stripTime * strip.maxSample;
        sumAmplitudes += strip.maxSample;
      }
 
      //finally compute cluster time
      time = time / sumAmplitudes;
    }

◆ applyELS3Time()

void applyELS3Time	(	const Belle2::SVD::RawCluster &	rawCluster,
		double &	time,
		double &	timeError,
		int &	firstFrame
	)

ELS3 Time Algorithm.

Definition at line 134 of file SVDClusterTime.cc.

    {
 
      // ISSUES:
      // 1. ELS3 tau hardcoded
      // 2. time error not computer
 
      timeError = 0;
      float m_ELS3tau = 55;
 
      //take the MaxSum 3 samples
      SVDMaxSumAlgorithm maxSum = SVDMaxSumAlgorithm(rawCluster.getClsSamples(false));
 
      std::vector<float> selectedSamples = maxSum.getSelectedSamples();
      firstFrame = maxSum.getFirstFrame();
 
      auto begin = selectedSamples.begin();
      const double E = std::exp(- m_apvClockPeriod / m_ELS3tau);
      const double E2 = E * E;
      const double E4 = E2 * E2;
      double a0 = (*begin);
      double a1 = (*(begin + 1));
      double a2 = (*(begin + 2));
 
      //compute raw time
      const double w = (a0 -  E2 * a2) / (2 * a0 + E * a1);
      auto rawtime_num  = 2 * E4 + w * E2;
      auto rawtime_den =  1 - E4 - w * (2 + E2);
      double rawtime = - m_apvClockPeriod * rawtime_num / rawtime_den;
 
      if (std::isnan(float(m_triggerBin)))
        B2FATAL("OOPS, we can't continue, you have to set the trigger bin!");
 
      if (m_returnRawClusterTime)
        time = rawtime;
      else
        time = m_ELS3TimeCal.getCorrectedTime(rawCluster.getSensorID(), rawCluster.isUSide(), 10, rawtime, m_triggerBin);
 
    }

◆ computeClusterTime()

virtual void computeClusterTime	(	Belle2::SVD::RawCluster &	rawCluster,
		double &	time,
		double &	timeError,
		int &	firstFrame
	)

pure virtual

computes the cluster time, timeError and FirstFrame

Implemented in SVDCoG3Time, SVDCoG6Time, and SVDELS3Time.

◆ setReturnRawClusterTime()

void setReturnRawClusterTime ( )

inline

set to return the raw cluster time instead of the calibrated one

Definition at line 40 of file SVDClusterTime.h.

41 {m_returnRawClusterTime = true;};

◆ setTriggerBin()

void setTriggerBin ( const int triggerBin )

inline

set the trigger bin

Definition at line 46 of file SVDClusterTime.h.

47 { m_triggerBin = triggerBin; };

Member Data Documentation

◆ m_apvClockPeriod

double m_apvClockPeriod = 1. / m_hwClock->getClockFrequency(Const::EDetector::SVD, "sampling")

protected

APV clock period.

Definition at line 80 of file SVDClusterTime.h.

◆ m_CoG3TimeCal

SVD3SampleCoGTimeCalibrations m_CoG3TimeCal

protected

CoG3 time calibration wrapper.

Definition at line 88 of file SVDClusterTime.h.

◆ m_CoG6TimeCal

SVDCoGTimeCalibrations m_CoG6TimeCal

protected

CoG6 time calibration wrapper.

Definition at line 86 of file SVDClusterTime.h.

◆ m_ELS3TimeCal

SVD3SampleELSTimeCalibrations m_ELS3TimeCal

protected

ELS3 time calibration wrapper.

Definition at line 90 of file SVDClusterTime.h.

◆ m_hwClock

DBObjPtr<HardwareClockSettings> m_hwClock

protected

Hardware Clocks.

Definition at line 77 of file SVDClusterTime.h.

◆ m_PulseShapeCal

SVDPulseShapeCalibrations m_PulseShapeCal

protected

SVDPulseShaper calibration wrapper.

Definition at line 83 of file SVDClusterTime.h.

◆ m_returnRawClusterTime

bool m_returnRawClusterTime = false

protected

to be used for time calibration

Definition at line 71 of file SVDClusterTime.h.

◆ m_triggerBin

int m_triggerBin = std::numeric_limits<int>::quiet_NaN()

protected

trigger bin

Definition at line 74 of file SVDClusterTime.h.

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

svd/reconstruction/include/SVDClusterTime.h
svd/reconstruction/src/SVDClusterTime.cc

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ SVDClusterTime()

◆ ~SVDClusterTime()

Member Function Documentation

◆ applyCoG3Time()

◆ applyCoG6Time()

◆ applyELS3Time()

◆ computeClusterTime()

◆ setReturnRawClusterTime()

◆ setTriggerBin()

Member Data Documentation

◆ m_apvClockPeriod

◆ m_CoG3TimeCal

◆ m_CoG6TimeCal

◆ m_ELS3TimeCal

◆ m_hwClock

◆ m_PulseShapeCal

◆ m_returnRawClusterTime

◆ m_triggerBin