#include <DTTTrigSyncTOFCorr.h>

Inheritance diagram for DTTTrigSyncTOFCorr:

Public Member Functions
	DTTTrigSyncTOFCorr (const edm::ParameterSet &config)
	Constructor.
virtual double	emulatorOffset (const DTWireId &wireId, double &tTrig, double &t0cell)
virtual double	offset (const DTWireId &wireId)
virtual double	offset (const DTLayer *layer, const DTWireId &wireId, const GlobalPoint &globPos, double &tTrig, double &wirePropCorr, double &tofCorr)
virtual void	setES (const edm::EventSetup &setup)
	Pass the Event Setup to the algo at each event.
virtual	~DTTTrigSyncTOFCorr ()
	Destructor.
Private Attributes
double	theBXspace
Static Private Attributes
static bool	debug
static int	theTOFCorrType
static double	theTTrig
static double	theVPropWire

Detailed Description

Concrete implementation of a DTTTrigBaseSync. This class define the offsets for RecHit building coherently to the digitization realized with the DTDigiSyncTOFCorr module. The offset is computes as:
offset = tTrig + wirePropCorr - tofCorr
where:

tTrig is a fixed offset defined in tTrig parameter (default 500 ns)
wirePropCorr is the correction for the signal propagation along the wire
tofCorr is the correction for the TOF of the particle set according to tofCorrType parameter:
0: tofCorrType = TOF from IP to 3D Hit position (globPos)
1: tofCorrType = TOF correction for distance difference between 3D center of the chamber and hit position
2: tofCorrType = TOF correction for distance difference between 3D center of the wire and hit position (This mode in available for backward compatibility)

The emulatorOffset is computed as:
offset = int(ttrig/BXspace)*BXspace
where:

ttrig from the fit of time box rising edge (taken from configuration, it is assumed to be in ns)
BXspace BX spacing (in ns). Taken from configuration (default 25ns).

NOTE: this should approximate what is seen online by the BTI

Date:: 2009/10/21 17:05:47

Revision:: 1.2

Author:: G. Cerminara - INFN Torino

Definition at line 52 of file DTTTrigSyncTOFCorr.h.

Constructor & Destructor Documentation

DTTTrigSyncTOFCorr::DTTTrigSyncTOFCorr ( const edm::ParameterSet & config )

Constructor.

Definition at line 22 of file DTTTrigSyncTOFCorr.cc.

References debug, edm::ParameterSet::getParameter(), and edm::ParameterSet::getUntrackedParameter().

                                                                   {
  theTTrig = config.getParameter<double>("tTrig"); // FIXME: Default was 500 ns
  theVPropWire = config.getParameter<double>("vPropWire"); // FIXME: Default was 24.4 cm/ns
  theTOFCorrType = config.getParameter<int>("tofCorrType"); // FIXME: Default was 1
  debug = config.getUntrackedParameter<bool>("debug");
  // spacing of BX in ns
  theBXspace  = config.getUntrackedParameter<double>("bxSpace", 25.);

}

DTTTrigSyncTOFCorr::~DTTTrigSyncTOFCorr ( ) [virtual]

Destructor.

Definition at line 34 of file DTTTrigSyncTOFCorr.cc.

{}

Member Function Documentation

double DTTTrigSyncTOFCorr::emulatorOffset	(	const DTWireId &	wireId,
		double &	tTrig,
		double &	t0cell
	)		`[virtual]`

Time (ns) to be subtracted to the digi time for emulation purposes It does not take into account TOF and signal propagation along the wire It also returns the different contributions separately:

tTrig is the offset (t_trig)
t0cell is the t0 from pulses (always 0 in this case)

Implements DTTTrigBaseSync.

Definition at line 141 of file DTTTrigSyncTOFCorr.cc.

                                                         {
  tTrig = theTTrig;
  t0cell = 0.;

  return int(tTrig/theBXspace)*theBXspace;
}

double DTTTrigSyncTOFCorr::offset	(	const DTLayer *	layer,
		const DTWireId &	wireId,
		const GlobalPoint &	globPos,
		double &	tTrig,
		double &	wirePropCorr,
		double &	tofCorr
	)		`[virtual]`

Time (ns) to be subtracted to the digi time, Parameters are the layer and the wireId to which the digi is referred and the estimation of the 3D hit position (globPos) It also returns the different contributions separately:

tTrig is the offset (t_trig)
wirePropCorr is the delay for signal propagation along the wire
tofCorr is the correction due to the particle TOF

Implements DTTTrigBaseSync.

Definition at line 38 of file DTTTrigSyncTOFCorr.cc.

References DTTopology::cellLenght(), DTLayer::chamber(), gather_cfg::cout, debug, Exception, PV3DBase< T, PVType, FrameType >::mag(), mag(), evf::evtn::offset(), GloballyPositioned< T >::position(), DTLayer::specificTopology(), GeomDet::surface(), GeomDet::toGlobal(), GeomDet::toLocal(), DTWireId::wire(), DTTopology::wirePosition(), and PV3DBase< T, PVType, FrameType >::y().

                                                   {
  tTrig = offset(wireId);

  //Compute the time spent in signal propagation along wire.
  // NOTE: the FE is always at y>0
  float halfL     = layer->specificTopology().cellLenght()/2;
  float wireCoord = layer->toLocal(globPos).y();
  float propgL    = halfL - wireCoord;
  wirePropCorr = propgL/theVPropWire;


  // Compute TOF correction treating it accordingly to
  // the tofCorrType card
  float flightToHit = globPos.mag();
  static const float cSpeed = 29.9792458; // cm/ns
  tofCorr = 0.;
  switch(theTOFCorrType) {
  case 0: {
    // In this mode the subtraction of the TOF from IP to
    // estimate 3D hit digi position is done here
    // (No correction is needed anymore)
    tofCorr = -flightToHit/cSpeed;
    break;
  }
  case 1: {
    // Correction for TOF from the center of the chamber to hit position
    const DTChamber * chamber = layer->chamber();
    double flightToChamber = chamber->surface().position().mag();
    tofCorr = (flightToChamber-flightToHit)/cSpeed;
    break;
  }
  case 2: {
    // TOF from 3D center of the wire to hit position
    float flightToWire =
      layer->toGlobal(LocalPoint(layer->specificTopology().wirePosition(wireId.wire()), 0., 0.)).mag();
    tofCorr = (flightToWire-flightToHit)/cSpeed;
    break;
  }
  default: {
    throw
      cms::Exception("[DTTTrigSyncTOFCorr]") << " Invalid parameter: tofCorrType = "
                                             << theTOFCorrType 
                                             << std::endl;
    break;
  }
  }

  if(debug) {
    cout << "[DTTTrigSyncTOFCorr] Offset (ns): " << tTrig + wirePropCorr - tofCorr << endl
         << "      various contributions are: " << endl
         << "      tTrig (ns):   " << tTrig << endl
         << "      Propagation along wire delay (ns): " <<  wirePropCorr << endl
         << "      TOF correction (ns): " << tofCorr << endl
         << endl;
  }
  //The global offset is the sum of various contributions
  return tTrig + wirePropCorr - tofCorr;
}

double DTTTrigSyncTOFCorr::offset ( const DTWireId & wireId ) [virtual]

Time (ns) to be subtracted to the digi time. It does not take into account TOF and signal propagation along the wire

Implements DTTTrigBaseSync.

Definition at line 102 of file DTTTrigSyncTOFCorr.cc.

                                                        {
  // Correction for the float to int conversion
  // (half a bin on average) in DTDigi constructor
  static const float f2i_convCorr = (25./64.); // ns
  //FIXME: This should be considered only if the Digi is constructed from a float....


  // The tTrig is taken from a parameter
  return theTTrig - f2i_convCorr;
}