AlignableCDCRecoHit Class Reference

This class is used to transfer CDC information to the track fit and Millepede. More...

#include <AlignableCDCRecoHit.h>

Inheritance diagram for AlignableCDCRecoHit:

Collaboration diagram for AlignableCDCRecoHit:

Public Member Functions
	~AlignableCDCRecoHit ()
	Destructor.
AlignableCDCRecoHit *	clone () const override
	Creating a copy of this hit.
virtual std::pair< std::vector< int >, TMatrixD >	globalDerivatives (const genfit::StateOnPlane *sop) override
	Labels and derivatives of residuals (local measurement coordinates) w.r.t. More...
virtual TMatrixD	localDerivatives (const genfit::StateOnPlane *sop) override
	Derivatives for (local) fit parameters. More...
	CDCRecoHit ()
	Inherit constructors.
	CDCRecoHit (const CDCHit *cdcHit, const genfit::TrackCandHit *trackCandHit)
	Inherit constructors.
WireID	getWireID () const
	Getter for WireID object.
genfit::SharedPlanePtr	constructPlane (const genfit::StateOnPlane &state) const override
	Methods that actually interface to Genfit.
std::vector< genfit::MeasurementOnPlane * >	constructMeasurementsOnPlane (const genfit::StateOnPlane &state) const override
	build MeasurementsOnPlane
virtual const genfit::HMatrixU *	constructHMatrix (const genfit::AbsTrackRep *) const override
	construct error matrix
std::vector< double >	timeDerivativesMeasurementsOnPlane (const genfit::StateOnPlane &state) const
	Get the time derivative of the MesuredStateOnPlane (derived from the track fit). More...
bool	getFlyByDistanceVector (B2Vector3D &pointingVector, B2Vector3D &trackDir, const genfit::AbsTrackRep *rep=NULL, bool usePlaneFromFit=false)
	Get the vector pointing from the wire to the fitted trajectory as well as the direction of the track in the fitted point. More...
void	setLeftRightResolution (int lr)
	select how to resolve the left/right ambiguity: -1: negative (left) side on vector (wire direction) x (track direction) 0: mirrors enter with same weight, DAF will decide. More...
bool	isLeftRightMeasurement () const override
	CDC RecoHits always have left-right ambiguity.
int	getLeftRightResolution () const override
	Getter for left/right passage flag.
const CDCHit *	getCDCHit () const
	get the pointer to the CDCHit object that was used to create this CDCRecoHit object. More...
TrackPoint *	getTrackPoint () const
void	setTrackPoint (TrackPoint *tp)
const TVectorD &	getRawHitCoords () const
TVectorD &	getRawHitCoords ()
const TMatrixDSym &	getRawHitCov () const
TMatrixDSym &	getRawHitCov ()
int	getDetId () const
int	getHitId () const
unsigned int	getDim () const
void	setRawHitCoords (const TVectorD &coords)
void	setRawHitCov (const TMatrixDSym &cov)
void	setDetId (int detId)
void	setHitId (int hitId)
virtual void	Print (const Option_t *="") const
virtual std::vector< int >	labels ()
	Vector of integer labels for calibration/alignment parameters available (must match #columns of derivatives(...)) More...
virtual TMatrixD	derivatives (const genfit::StateOnPlane *)
	Derivatives of residuals (local measurement coordinates) w.r.t. More...
virtual std::vector< int >	localLabels ()
	Vector of integer labels for local calibration parameters available (must match #columns of localDerivatives(...)) More...

Static Public Member Functions
static void	setTranslators (CDC::ADCCountTranslatorBase *const adcCountTranslator, CDC::CDCGeometryTranslatorBase *const cdcGeometryTranslator, CDC::TDCCountTranslatorBase *const tdcCountTranslator, bool useTrackTime=false, bool cosmics=false)
	Setter for the Translators.

Static Public Attributes
static bool	s_enableTrackT0LocalDerivative = true
	Static enabling(true) or disabling(false) addition of local derivative for track T0.
static bool	s_enableWireSaggingGlobalDerivative = false
	Static enabling(true) or disabling(false) addition of global derivative for wire sagging coefficient (per wire)
static bool	s_enableWireByWireAlignmentGlobalDerivatives = false
	Static enabling(true) or disabling(false) addition of global derivatives for wire-by-wire alignment.

Protected Member Functions
	ClassDefOverride (CDCRecoHit, 10)
	ROOT Macro.

Protected Attributes
unsigned short	m_tdcCount
	TDC Count as out of CDCHit.
unsigned short	m_adcCount
	ADC Count as out of CDCHit.
WireID	m_wireID
	Wire Identifier.
const CDCHit *	m_cdcHit
	Pointer to the CDCHit used to created this CDCRecoHit.
signed char	m_leftRight
	Flag showing left/right passage.
TVectorD	rawHitCoords_
TMatrixDSym	rawHitCov_
int	detId_
int	hitId_
TrackPoint *	trackPoint_
	Pointer to TrackPoint where the measurement belongs to.

Static Protected Attributes
static std::unique_ptr< CDC::ADCCountTranslatorBase >	s_adcCountTranslator = 0
	Object for ADC Count translation.
static std::unique_ptr< CDC::CDCGeometryTranslatorBase >	s_cdcGeometryTranslator = 0
	Object for geometry translation.
static std::unique_ptr< CDC::TDCCountTranslatorBase >	s_tdcCountTranslator = 0
	Object for getting drift-length and -resolution.
static bool	s_useTrackTime = false
	Whether to use the track time or not when building the measurementOnPlane. More...
static bool	s_cosmics = false
	Switch to use cosmic events, or physics events from IP. More...

Private Member Functions
	ClassDefOverride (AlignableCDCRecoHit, 1)
	ROOT Macro.

Detailed Description

This class is used to transfer CDC information to the track fit and Millepede.

Definition at line 32 of file AlignableCDCRecoHit.h.

Member Function Documentation

derivatives()

virtual TMatrixD derivatives ( const genfit::StateOnPlane *  )

inlinevirtualinherited

Derivatives of residuals (local measurement coordinates) w.r.t.

alignment/calibration parameters Matrix "G" of derivatives valid for given prediction of track state:

G(i, j) = d_residual_i/d_parameter_j

For 2D measurement (u,v):

G = ( du/da du/db du/dc ... ) ( dv/da dv/db dv/dc ... )

for calibration parameters a, b, c.

For 1D measurement both forms are allowed:

G = ( 0 0 0 ... ) ( dv/da dv/db dv/dc ... ) for V-strip,

G = ( du/da du/db du/dc ... ) ( 0 0 0 ... ) for U-strip,

or :

G = ( d_sensitive/da d_sensitive/db d_sensitive/dc ... ) as matrix with one row.

A possible algorithm using these derivatives should be able to resolve this based on the measurement HMatrix. Measurements with more dimesions (slopes, curvature) should provide full 4-5Dx(n params) matrix (state as (q/p, u', v', u, v) or (u', v', u, v))

Parameters

sop	Predicted state of the track as linearization point around which derivatives of alignment/calibration parameters shall be computed

Returns

TMatrixD Matrix with #rows = dimension of residual, #columns = number of parameters. #columns must match labels().size().

Definition at line 129 of file ICalibrationParametersDerivatives.h.

getCDCHit()

const CDCHit* getCDCHit ( ) const

inlineinherited

get the pointer to the CDCHit object that was used to create this CDCRecoHit object.

Can be NULL if CDCRecoHit was not created with the CDCRecoHit(const CDCHit* cdcHit) constructor

Definition at line 123 of file CDCRecoHit.h.

getFlyByDistanceVector()

bool getFlyByDistanceVector ( B2Vector3D &  pointingVector, B2Vector3D &  trackDir, const genfit::AbsTrackRep *  rep = NULL, bool  usePlaneFromFit = false  )

inherited

Get the vector pointing from the wire to the fitted trajectory as well as the direction of the track in the fitted point.

Uses the cardinal TrackRep if rep == NULL. Returns false if the track is not fitted in this point for the requested TrackRep. If the hit does not belong to a track, an error is issued and false returned. If usePlaneFromFit is used, constructPlane is not called to evaluate the closest point on the wire to the track. Instead the origin of the plane of the fitted state is used (which will be the same point if the wire is not bent).

Definition at line 370 of file CDCRecoHit.cc.

{
  const genfit::TrackPoint* tp = this->getTrackPoint();
  if (!tp) {
    B2ERROR("No genfit::TrackPoint for CDCRecoHit.");
    return false;
  }
  const genfit::AbsFitterInfo* fi = tp->getFitterInfo(rep);
  if (!fi) {
    B2DEBUG(200, "No genfit::AbsFitterInfo for this CDCRecoHit.");
    return false;
  }
 
  const genfit::MeasuredStateOnPlane& mop = fi->getFittedState();
  B2Vector3D fittedPoca = mop.getPos();
  // constructPlane places the coordinate center in the POCA to the
  // wire.  Using this is the default behavior.  If this should be too
  // slow, as it has to re-evaluate the POCA, alternatively the user
  // can set usePlaneFromFit which uses the plane determined by the
  // track fit.
  B2Vector3D pocaOnWire = (usePlaneFromFit
                           ? mop.getPlane()->getO()
                           : this->constructPlane(mop)->getO());
 
  // The vector from the wire to the track.
  pointingVector = fittedPoca - pocaOnWire;
 
  trackDir = mop.getMom();
  trackDir.SetMag(1.);
  return true;
}

globalDerivatives()

std::pair< std::vector< int >, TMatrixD > globalDerivatives ( const genfit::StateOnPlane *  sop )

overridevirtual

Labels and derivatives of residuals (local measurement coordinates) w.r.t.

alignment/calibration parameters Matrix "G" of derivatives valid for given prediction of track state:

G(i, j) = d_residual_i/d_parameter_j

For 2D measurement (u,v):

G = ( du/da du/db du/dc ... ) ( dv/da dv/db dv/dc ... )

for calibration parameters a, b, c.

For 1D measurement:

G = ( 0 0 0 ... ) ( dv/da dv/db dv/dc ... ) for V-strip,

G = ( du/da du/db du/dc ... ) ( 0 0 0 ... ) for U-strip,

Measurements with more dimesions (slopes, curvature) should provide full 4-5Dx(n params) matrix (state as (q/p, u', v', u, v) or (u', v', u, v))

Parameters

sop	Predicted state of the track as linearization point around which derivatives of alignment/calibration parameters shall be computed

Returns

pair<vector<int>, TMatrixD> With matrix with #rows = dimension of residual, #columns = number of parameters. #columns must match vector<int>.size().

Reimplemented from ICalibrationParametersDerivatives.

Definition at line 29 of file AlignableCDCRecoHit.cc.

{
  GlobalDerivatives globals;
  unsigned short LR = (int(m_leftRight) > 0.) ? 1 : 0;
 
  const TVector3& mom = sop->getMom();
  const TVector3& wirePositon = sop->getPlane()->getO();
  const unsigned short layer = getWireID().getICLayer();
 
  CDCGeometryPar& cdcgeo = CDCGeometryPar::Instance();
  const double alpha = cdcgeo.getAlpha(wirePositon, mom);
  const double theta = cdcgeo.getTheta(mom);
  const TVectorD& stateOnPlane = sop->getState();
  const double driftLengthEstimate = std::abs(stateOnPlane(3));
  const double driftTime = cdcgeo.getDriftTime(driftLengthEstimate, layer, LR, alpha, theta);
  const double driftVelocity = cdcgeo.getDriftV(driftTime, layer, LR, alpha, theta);
 
  // CDC Calibration -------------------------------------------------
 
  // T0 calibration (per wire) TODO check sign!!!
  if (driftTime > 20 && driftTime < 200 && fabs(driftVelocity) < 1.0e-2) {
    globals.add(
      GlobalLabel::construct<CDCTimeZeros>(getWireID(), 0),
      driftVelocity * double(int(m_leftRight))
    );
  }
 
  // Time-walk calibration (per board) TODO checksign!!!
  globals.add(
    GlobalLabel::construct<CDCTimeWalks>(CDCGeometryPar::Instance().getBoardID(getWireID()), 0),
    driftVelocity * 1. / sqrt(m_adcCount) * double(int(m_leftRight))
  );
 
  // CDC Alignment ---------------------------------------------------
 
  auto tdir = sop->getDir();
  auto ndir = sop->getPlane()->getNormal();
  auto udir = sop->getPlane()->getU();
  auto vdir = sop->getPlane()->getV();
  auto pos  = sop->getPos();
 
  auto tn = tdir[0] * ndir[0] + tdir[1] * ndir[1] + tdir[2] * ndir [2];
  // d residual / d measurement
  auto drdm = TMatrixD(3, 3);
  drdm.UnitMatrix();
  for (int i = 0; i < 3; ++i) {
    for (int j = 0; j < 3; ++j) {
      drdm(i, j) -= tdir[i] * ndir[j] / tn;
    }
  }
  // d measurement / d global rigid body param
  auto dmdg = TMatrixD(3, 6);
  dmdg.Zero();
  dmdg[0][0] = 1.; dmdg[0][4] = -pos[2]; dmdg[0][5] =  pos[1];
  dmdg[1][1] = 1.; dmdg[1][3] =  pos[2]; dmdg[1][5] = -pos[0];
  dmdg[2][2] = 1.; dmdg[2][3] = -pos[1]; dmdg[2][4] =  pos[0];
  // d local residual / d global residual
  auto drldrg = TMatrixD(3, 3);
  for (int i = 0; i < 3; ++i) {
    drldrg(0, i) = udir[i];
    drldrg(1, i) = vdir[i];
    drldrg(2, i) = ndir[i];
  }
  // d local residual / d global rigid body param
  auto drldg = drldrg * (drdm * dmdg);
 
  // wire ends
  const double zWireM = s_cdcGeometryTranslator->getWireBackwardPosition(getWireID(), CDCGeometryPar::c_Aligned)[2];
  const double zWireP = s_cdcGeometryTranslator->getWireForwardPosition(getWireID(), CDCGeometryPar::c_Aligned)[2];
  // relative Z position [0..1]
  const double zRel = std::max(0., std::min(1., (pos[2] - zWireM) / (zWireP - zWireM)));
 
  // Layer alignment
  // wire 511 = no wire (0 is reserved for existing wires) - this has to be compatible with code in CDCGeometryPar::setWirPosAlignParams
  auto layerID = WireID(getWireID().getICLayer(), 511);
 
  // Alignment of layer X (bwd)
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerX),
    drldg(0, 0)
  );
 
  // Alignment of layer Y (bwd)
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerY),
    drldg(0, 1)
  );
 
  // Alignment of layer rotation (gamma) (bwd)
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerPhi),
    drldg(0, 5)
  );
 
  // Difference between wire ends (end plates)
  // Alignment of layer dX, dX = foward - backward endplate
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerDx),
    drldg(0, 0) * zRel
  );
 
  // Alignment of layer dY, dY = foward - backward endplate
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerDy),
    drldg(0, 1) * zRel
  );
 
  // Alignment of layer rotation difference d(gamma or phi), dPhi = foward - backward endplate
  globals.add(
    GlobalLabel::construct<CDCAlignment>(layerID, CDCAlignment::layerDPhi),
    drldg(0, 5) * zRel
  );
 
  //WARNING: experimental (disabled by default)
  // Wire-by-wire alignment
  if (s_enableWireByWireAlignmentGlobalDerivatives) {
    // How much shift (in X or Y) on BWD wire-end will change the residual at estimated track crossing
    // with the wire (at relative z-position on wire = zRel)
    double zRelM = fabs(1. - zRel);
    // Same as above but for FWD wire-end (residual at zRel = zRel * delta(X or Y at FWD wire-end)
    double zRelP = fabs(zRel - 0.);
 
    // Alignment of wires X in global coords at BWD wire-end
    globals.add(
      GlobalLabel::construct<CDCAlignment>(getWireID().getEWire(), CDCAlignment::wireBwdX),
      drldg(0, 0) * zRelM
    );
    // Alignment of wires X in global coords at FWD wire-end
    globals.add(
      GlobalLabel::construct<CDCAlignment>(getWireID().getEWire(), CDCAlignment::wireFwdX),
      drldg(0, 0) * zRelP
    );
 
    // Alignment of wires Y in global coords at BWD wire-end
    globals.add(
      GlobalLabel::construct<CDCAlignment>(getWireID().getEWire(), CDCAlignment::wireBwdY),
      drldg(0, 1) * zRelM
    );
    // Alignment of wires Y in global coords at FWD wire-end
    globals.add(
      GlobalLabel::construct<CDCAlignment>(getWireID().getEWire(), CDCAlignment::wireFwdY),
      drldg(0, 1) * zRelP
    );
  }
 
  //WARNING: experimental (disabled by default)
  //TODO: missing some factors (we do not align directly the wire-sag coefficient, but
  // wire tension ... coef = pi * ro * r * r / 8 / tension
  //TODO: need to get these numbers from CDCGeometryPar!
  if (s_enableWireSaggingGlobalDerivative) {
    globals.add(
      GlobalLabel::construct<CDCAlignment>(getWireID().getEWire(), CDCAlignment::wireTension),
      drldg(0, 1) * 4.0 * zRel * (1.0 - zRel)
    );
  }
 
  return globals;
}

labels()

virtual std::vector<int> labels ( )

inlinevirtualinherited

Vector of integer labels for calibration/alignment parameters available (must match #columns of derivatives(...))

unique across all sub-detectors in calibration

Returns

std::vector< int > Vector of integer labels

Definition at line 90 of file ICalibrationParametersDerivatives.h.

localDerivatives()

TMatrixD localDerivatives ( const genfit::StateOnPlane *  sop )

overridevirtual

Derivatives for (local) fit parameters.

Parameters

sop	State on virtual plane to calculate derivatives

Returns

TMatrixD of local derivatives, #columns=#params, #row=2 (or measurement dimension if > 2)

Reimplemented from ICalibrationParametersDerivatives.

Definition at line 189 of file AlignableCDCRecoHit.cc.

localLabels()

virtual std::vector<int> localLabels ( )

inlinevirtualinherited

Vector of integer labels for local calibration parameters available (must match #columns of localDerivatives(...))

This will be usually ignored (e.g. does not have to match localDerivatives), but it is a good practice to return vector of zeros of correct size

Returns

std::vector< int > Vector of integer labels

Definition at line 151 of file ICalibrationParametersDerivatives.h.

setLeftRightResolution()

void setLeftRightResolution ( int  lr )

inlineinherited

select how to resolve the left/right ambiguity: -1: negative (left) side on vector (wire direction) x (track direction) 0: mirrors enter with same weight, DAF will decide.

1: positive (right) side on vector (wire direction) x (track direction) where the wire direction is pointing towards +z except for small corrections such as stereo angle, sagging

Definition at line 111 of file CDCRecoHit.h.

timeDerivativesMeasurementsOnPlane()

std::vector< double > timeDerivativesMeasurementsOnPlane ( const genfit::StateOnPlane &  state ) const

inherited

Get the time derivative of the MesuredStateOnPlane (derived from the track fit).

Definition at line 263 of file CDCRecoHit.cc.

Member Data Documentation

s_cosmics

bool s_cosmics = false

staticprotectedinherited

Switch to use cosmic events, or physics events from IP.

Default value is 0, which means "physics event" mode.

Definition at line 147 of file CDCRecoHit.h.

s_useTrackTime

bool s_useTrackTime = false

staticprotectedinherited

Whether to use the track time or not when building the measurementOnPlane.

This needs to be in sync with the TDCCountTranslator.

Definition at line 142 of file CDCRecoHit.h.

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

• alignment/reconstruction/include/AlignableCDCRecoHit.h
• alignment/reconstruction/src/AlignableCDCRecoHit.cc