MultipleScatteringParametrisation Class Reference

#include <MultipleScatteringParametrisation.h>

Public Types
enum	Consecutive { notAssumeConsecutive, useConsecutive }

Public Member Functions
	MultipleScatteringParametrisation (const DetLayer *layer, const MSLayersKeeper *layerKeeper)
float	operator() (float pt, float cotTheta, float transverseIP=0.) const
float	operator() (float pt, float cotTheta, const PixelRecoPointRZ &point, float transverseIP=0.) const
float	operator() (float pt, float cotTheta, const PixelRecoPointRZ &point, int ol) const
float	operator() (float pt, const PixelRecoPointRZ &point1, const PixelRecoPointRZ &point2, Consecutive consecutive=notAssumeConsecutive, float transverseIP=0.) const
float	operator() (float pT, const PixelRecoPointRZ &pointV, const PixelRecoPointRZ &pointO, int ol) const

Private Attributes
MSLayer	theLayer
MSLayersKeeper const *	theLayerKeeper = nullptr

Static Private Attributes
static const float	x0ToSigma = 0.0136f

Detailed Description

Parametrisation of multiple scattering sigma in tracker.

Definition at line 16 of file MultipleScatteringParametrisation.h.

Member Enumeration Documentation

Consecutive

enum MultipleScatteringParametrisation::Consecutive

Enumerator
notAssumeConsecutive
useConsecutive

Definition at line 18 of file MultipleScatteringParametrisation.h.

{ notAssumeConsecutive, useConsecutive };

Constructor & Destructor Documentation

MultipleScatteringParametrisation()

MultipleScatteringParametrisation::MultipleScatteringParametrisation	(	const DetLayer *	layer,
		const MSLayersKeeper *	layerKeeper
	)

Definition at line 21 of file MultipleScatteringParametrisation.cc.

References MSLayersKeeper::layer(), pixelTopology::layer, theLayer, and theLayerKeeper.

    : theLayerKeeper(layerKeeper) {
  if (layer) {
    theLayer = theLayerKeeper->layer(layer);
  }
}

Member Function Documentation

operator()() [1/5]

float MultipleScatteringParametrisation::operator()	(	float	pt,
		float	cotTheta,
		float	transverseIP = 0.
	)		const

MS sigma at the layer for which parametrisation is initialised; particle assumed to come from nominal vertex, "fast" methods called

Definition at line 30 of file MultipleScatteringParametrisation.cc.

References pv::pT, MSLayer::sumX0D(), theLayer, and x0ToSigma.

                                                                                         {
  float sumX0D = theLayer.sumX0D(cotTheta);
  return x0ToSigma * sumX0D / pT;
}

operator()() [2/5]

float MultipleScatteringParametrisation::operator()	(	float	pt,
		float	cotTheta,
		const PixelRecoPointRZ &	point,
		float	transverseIP = 0.
	)		const

MS sigma at the layer for which parametrisation is initialised; particle assumed to come from constraint point (inner to layer). layer by layer contribution is calculated

Definition at line 36 of file MultipleScatteringParametrisation.cc.

References MSLayer::crossing(), MSLayersKeeper::layers(), pv::pT, MSLayersAtAngle::sumX0D(), theLayer, theLayerKeeper, qcdUeDQM_cfi::tip, and x0ToSigma.

                                                                     {
  PixelRecoLineRZ lineIO(pointI, cotTheta, tip);
  PixelRecoPointRZ pointO = theLayer.crossing(lineIO).first;

  const MSLayersAtAngle &layersAtEta = theLayerKeeper->layers(cotTheta);

  float sumX0D = layersAtEta.sumX0D(pointI, pointO);
  return x0ToSigma * sumX0D / pT;
}

operator()() [3/5]

float MultipleScatteringParametrisation::operator()	(	float	pt,
		float	cotTheta,
		const PixelRecoPointRZ &	point,
		int	ol
	)		const

Definition at line 49 of file MultipleScatteringParametrisation.cc.

References MSLayer::crossing(), MSLayersKeeper::layers(), pv::pT, MSLayer::seqNum(), MSLayersAtAngle::sumX0D(), theLayer, theLayerKeeper, and x0ToSigma.

                                                                  {
  PixelRecoLineRZ lineIO(pointI, cotTheta);
  PixelRecoPointRZ pointO = theLayer.crossing(lineIO).first;

  const MSLayersAtAngle &layersAtEta = theLayerKeeper->layers(cotTheta);

  float sumX0D = layersAtEta.sumX0D(il, theLayer.seqNum(), pointI, pointO);
  return x0ToSigma * sumX0D / pT;
}

operator()() [4/5]

float MultipleScatteringParametrisation::operator()	(	float	pt,
		const PixelRecoPointRZ &	point1,
		const PixelRecoPointRZ &	point2,
		Consecutive	consecutive = notAssumeConsecutive,
		float	transverseIP = 0.
	)		const

MS sigma at the layer for which parametrisation is initialised; particle assumed to be measured at point1 and point2, it is assumed that layer is between point1 and point2. layer by layer contribution is calculated

Definition at line 63 of file MultipleScatteringParametrisation.cc.

References PixelRecoLineRZ::cotLine(), MSLayer::crossing(), MSLayersKeeper::layers(), pv::pT, PixelRecoPointRZ::r(), mathSSE::sqrt(), MSLayersAtAngle::sumX0D(), theLayer, theLayerKeeper, qcdUeDQM_cfi::tip, useConsecutive, MSLayer::x0(), and x0ToSigma.

                                                                     {
  PixelRecoLineRZ lineIO(pointI, pointO, tip);
  PixelRecoPointRZ pointM = theLayer.crossing(lineIO).first;
  float cotTheta = lineIO.cotLine();

  if (consecutive == useConsecutive) {
    float dist = fabs((pointO.r() - pointM.r()) * (pointM.r() - pointI.r()) / (pointO.r() - pointI.r()));
    return x0ToSigma * sqrt(theLayer.x0(cotTheta)) * dist / pT;
  } else {
    const MSLayersAtAngle &layersAtEta = theLayerKeeper->layers(cotTheta);
    float sumX0D = layersAtEta.sumX0D(pointI, pointM, pointO);
    return x0ToSigma * sumX0D / pT;
  }
}

operator()() [5/5]

float MultipleScatteringParametrisation::operator()	(	float	pT,
		const PixelRecoPointRZ &	pointV,
		const PixelRecoPointRZ &	pointO,
		int	ol
	)		const

Definition at line 82 of file MultipleScatteringParametrisation.cc.

References PixelRecoLineRZ::cotLine(), MSLayer::crossing(), MSLayersKeeper::layers(), pv::pT, MSLayer::seqNum(), MSLayersAtAngle::sumX0D(), theLayer, theLayerKeeper, x0ToSigma, and PixelRecoPointRZ::z().

                                                                  {
  PixelRecoLineRZ lineIO(pointV, pointO);
  PixelRecoPointRZ pointI = theLayer.crossing(lineIO).first;
  float cotTheta = lineIO.cotLine();

  const MSLayersAtAngle &layersAtEta = theLayerKeeper->layers(cotTheta);
  float sumX0D = layersAtEta.sumX0D(pointV.z(), theLayer.seqNum(), ol, pointI, pointO);
  return x0ToSigma * sumX0D / pT;
}

Member Data Documentation

theLayer

MSLayer MultipleScatteringParametrisation::theLayer

private

Definition at line 46 of file MultipleScatteringParametrisation.h.

Referenced by MultipleScatteringParametrisation(), and operator()().

theLayerKeeper

MSLayersKeeper const* MultipleScatteringParametrisation::theLayerKeeper = nullptr

private

Definition at line 47 of file MultipleScatteringParametrisation.h.

Referenced by MultipleScatteringParametrisation(), and operator()().

x0ToSigma

const float MultipleScatteringParametrisation::x0ToSigma = 0.0136f

staticprivate

Definition at line 48 of file MultipleScatteringParametrisation.h.

Referenced by operator()().