DTTTrigSyncFromDB Class Reference

#include <DTTTrigSyncFromDB.h>

Inheritance diagram for DTTTrigSyncFromDB:

Public Member Functions
	DTTTrigSyncFromDB (const edm::ParameterSet &config)
	Constructor. More...
virtual double	emulatorOffset (const DTWireId &wireId, double &tTrig, double &t0cell)
virtual double	offset (const DTLayer *layer, const DTWireId &wireId, const GlobalPoint &globPos, double &tTrig, double &wirePropCorr, double &tofCorr)
double	offset (const DTWireId &wireId)
virtual void	setES (const edm::EventSetup &setup)
	Pass the Event Setup to the algo at each event. More...
virtual	~DTTTrigSyncFromDB ()
	Destructor. More...
Public Member Functions inherited from DTTTrigBaseSync
	DTTTrigBaseSync ()
	Constructor. More...
virtual double	emulatorOffset (const DTWireId &wireId)
double	offset (const DTLayer *layer, const DTWireId &wireId, const GlobalPoint &globalPos)
virtual	~DTTTrigBaseSync ()
	Destructor. More...

Private Attributes
bool	doT0Correction
bool	doTOFCorrection
bool	doWirePropCorrection
double	theBXspace
int	theTOFCorrType
std::string	thetTrigLabel
double	theVPropWire
int	theWirePropCorrType
const DTTtrig *	tTrigMap
const DTT0 *	tZeroMap

Static Private Attributes
static bool	debug = false

Detailed Description

Concrete implementation of a DTTTrigBaseSync. This class define the offset for RecHit building of data and simulation. The offset is computes as:
offset = t0 + tTrig + wirePropCorr - tofCorr
where:

• t0 from test pulses (taken from DB, it is assumed to be in ns; can be switched off)
• ttrig from the fit of time boxrising edge (taken from DB, it is assumed to be in ns) (At the moment a single value is read for ttrig offset but this may change in the future)
• signal propagation along the wire (can be switched off): it is assumed the ttrig accounts on average for correction from the center of the wire to the frontend. Here we just have to correct for the distance of the hit from the wire center.
• TOF correction (can be switched off for cosmics): the ttrig already accounts for average TOF correction, depending on the granularity used for the ttrig computation we just have to correct for the TOF from the center of the chamber, SL, layer or wire to the hit position. NOTE: particles are assumed as coming from the IP.

The emulatorOffset is computed as:
offset = int(ttrig/BXspace)*BXspace + t0
where:

• t0 from test pulses (taken from DB, it is assumed to be in ns; can be switched off)
• ttrig from the fit of time box rising edge (taken from DB, it is assumed to be in ns)
• BXspace BX spacing (in ns). Can be configured.

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

Date:

2009/10/21 17:05:47

Revision:

1.4

Author

G. Cerminara - INFN Torino

Definition at line 56 of file DTTTrigSyncFromDB.h.

Constructor & Destructor Documentation

DTTTrigSyncFromDB::DTTTrigSyncFromDB

(

const edm::ParameterSet &

config

)

Constructor.

Definition at line 29 of file DTTTrigSyncFromDB.cc.

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

                                                              {
  debug = config.getUntrackedParameter<bool>("debug");
  // The velocity of signal propagation along the wire (cm/ns)
  theVPropWire = config.getParameter<double>("vPropWire");
  // Switch on/off the T0 correction from pulses
  doT0Correction = config.getParameter<bool>("doT0Correction");
  // Switch on/off the TOF correction for particles from IP
  doTOFCorrection = config.getParameter<bool>("doTOFCorrection");
  theTOFCorrType = config.getParameter<int>("tofCorrType");
  // Switch on/off the correction for the signal propagation along the wire
  doWirePropCorrection = config.getParameter<bool>("doWirePropCorrection");
  theWirePropCorrType = config.getParameter<int>("wirePropCorrType");
  // spacing of BX in ns
  theBXspace  = config.getUntrackedParameter<double>("bxSpace", 25.);

  thetTrigLabel = config.getParameter<string>("tTrigLabel");
}

DTTTrigSyncFromDB::~DTTTrigSyncFromDB ( )

virtual

Destructor.

Definition at line 49 of file DTTTrigSyncFromDB.cc.

{}

Member Function Documentation

double DTTTrigSyncFromDB::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

Implements DTTTrigBaseSync.

Definition at line 208 of file DTTTrigSyncFromDB.cc.

References gather_cfg::cout, DTTimeUnits::ns, and DTLayerId::superlayerId().

                                     {
  float t0 = 0;
  float t0rms = 0;
  if(doT0Correction)
    {
      // Read the t0 from pulses for this wire (ns)
       tZeroMap->get(wireId,
             t0,
             t0rms,
                 DTTimeUnits::ns);

    }

  // Read the ttrig for this wire
  float ttrigMean = 0;
  float ttrigSigma = 0;
  float kFactor = 0;
  // FIXME: should check the return value of the DTTtrigRcd::get(..) method
  if(tTrigMap->get(wireId.superlayerId(),
           ttrigMean,
           ttrigSigma,
           kFactor,
           DTTimeUnits::ns) != 0) {
    cout << "[DTTTrigSyncFromDB]*Error: ttrig not found for SL: " << wireId.superlayerId() << endl;
//     FIXME: LogError.....
  }
  
  tTrig = ttrigMean + kFactor * ttrigSigma;
  t0cell = t0;

  return int(tTrig/theBXspace)*theBXspace + t0cell;
}

double DTTTrigSyncFromDB::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)

Implements DTTTrigBaseSync.

Definition at line 75 of file DTTTrigSyncFromDB.cc.

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

                                   {
  // Correction for the float to int conversion while writeing the ttrig in ns into an int variable
  // (half a bin on average)
  // FIXME: this should disappear as soon as the ttrig object will become a float
  //   static const float f2i_convCorr = (25./64.); // ns //FIXME: check how the conversion is performed

  tTrig = offset(wireId);

  // Compute the time spent in signal propagation along wire.
   // NOTE: the FE is always at y>0
  wirePropCorr = 0;
  if(doWirePropCorrection) {
    switch(theWirePropCorrType){
      // The ttrig computed from the timebox accounts on average for the signal propagation time
      // from the center of the wire to the frontend. Here we just have to correct for
      // the distance of the hit from the wire center.
    case 0: {
      float wireCoord = layer->toLocal(globPos).y();
      wirePropCorr = -wireCoord/theVPropWire;
      break;
      // FIXME: What if hits used for the time box are not distributed uniformly along the wire?
    }
    //On simulated data you need to subtract the total propagation time 
    case 1: {
      float halfL     = layer->specificTopology().cellLenght()/2;
      float wireCoord = layer->toLocal(globPos).y();
      float propgL    = halfL - wireCoord;
      wirePropCorr = propgL/theVPropWire;
      break;
    }
    default: {
    throw
      cms::Exception("[DTTTrigSyncFromDB]") << " Invalid parameter: wirePropCorrType = "
                         << theWirePropCorrType 
                         << std::endl;
    break;
    }
    }
  }

  // Compute TOF correction:
  tofCorr = 0.;
  // TOF Correction can be switched off with appropriate parameter
  if(doTOFCorrection) {
    float flightToHit = globPos.mag();
    static const float cSpeed = 29.9792458; // cm/ns
    switch(theTOFCorrType) {
    case 0: {
      // The ttrig computed from the real data accounts on average for the TOF correction 
      // Depending on the granularity used for the ttrig computation we just have to correct for the
      // TOF from the center of the chamber, SL, layer or wire to the hit position.
      // At the moment only SL granularity is considered
      // Correction for TOF from the center of the SL to hit position
      const DTSuperLayer *sl = layer->superLayer();
      double flightToSL = sl->surface().position().mag();
      tofCorr = (flightToSL-flightToHit)/cSpeed;
      break;
    }
    case 1: {
      // On simulated data you need to consider only the TOF from 3D center of the wire to hit position 
      // (because the TOF from the IP to the wire has been already subtracted in the digitization: 
      // SimMuon/DTDigitizer/DTDigiSyncTOFCorr.cc corrType=2)
      float flightToWire =
    layer->toGlobal(LocalPoint(layer->specificTopology().wirePosition(wireId.wire()), 0., 0.)).mag();
      tofCorr = (flightToWire-flightToHit)/cSpeed;
      break;
    }
    default: {
      throw
    cms::Exception("[DTTTrigSyncFromDB]") << " Invalid parameter: tofCorrType = "
                          << theTOFCorrType 
                          << std::endl;
      break;
    }
    }
  }


  if(debug) {
    cout << "[DTTTrigSyncFromDB] Channel: " << wireId << endl
     << "      Offset (ns): " << tTrig + wirePropCorr - tofCorr << endl
     << "      various contributions are: " << endl
     << "      tTrig + t0 (ns):   " << tTrig << endl
     //<< "      tZero (ns):   " << t0 << 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 DTTTrigSyncFromDB::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 172 of file DTTTrigSyncFromDB.cc.

References gather_cfg::cout, DTTimeUnits::ns, and DTLayerId::superlayerId().

                                                       {
  float t0 = 0;
  float t0rms = 0;
  if(doT0Correction)
    {
      // Read the t0 from pulses for this wire (ns)
       tZeroMap->get(wireId,
             t0,
             t0rms,
                 DTTimeUnits::ns);

    }

  // Read the ttrig for this wire
  float ttrigMean = 0;
  float ttrigSigma = 0;
  float kFactor = 0;
  // FIXME: should check the return value of the DTTtrigRcd::get(..) method
  if(tTrigMap->get(wireId.superlayerId(),
           ttrigMean,
           ttrigSigma,
           kFactor,
           DTTimeUnits::ns) != 0) {
    cout << "[DTTTrigSyncFromDB]*Error: ttrig not found for SL: " << wireId.superlayerId() << endl;
//     FIXME: LogError.....
  }
  
  return t0 + ttrigMean + kFactor * ttrigSigma;

}

void DTTTrigSyncFromDB::setES ( const edm::EventSetup &  setup )

virtual

Pass the Event Setup to the algo at each event.

Implements DTTTrigBaseSync.

Definition at line 53 of file DTTTrigSyncFromDB.cc.

References gather_cfg::cout, debug, and edm::EventSetup::get().

                                                     {
  if(doT0Correction)
    {
      // Get the map of t0 from pulses from the Setup
      ESHandle<DTT0> t0Handle;
      setup.get<DTT0Rcd>().get(t0Handle);
      tZeroMap = &*t0Handle;
      if(debug) {
    cout << "[DTTTrigSyncFromDB] t0 version: " << tZeroMap->version()<<endl;
      }
    }

  // Get the map of ttrig from the Setup
  ESHandle<DTTtrig> ttrigHandle;
  setup.get<DTTtrigRcd>().get(thetTrigLabel,ttrigHandle);
  tTrigMap = &*ttrigHandle;
    if(debug) {
      cout << "[DTTTrigSyncFromDB] ttrig version: " << tTrigMap->version() << endl;
  }
}

Member Data Documentation

bool DTTTrigSyncFromDB::debug = false

staticprivate

Definition at line 101 of file DTTTrigSyncFromDB.h.

bool DTTTrigSyncFromDB::doT0Correction

private

Definition at line 105 of file DTTTrigSyncFromDB.h.

bool DTTTrigSyncFromDB::doTOFCorrection

private

Definition at line 107 of file DTTTrigSyncFromDB.h.

bool DTTTrigSyncFromDB::doWirePropCorrection

private

Definition at line 110 of file DTTTrigSyncFromDB.h.

double DTTTrigSyncFromDB::theBXspace

private

Definition at line 113 of file DTTTrigSyncFromDB.h.

int DTTTrigSyncFromDB::theTOFCorrType

private

Definition at line 108 of file DTTTrigSyncFromDB.h.

std::string DTTTrigSyncFromDB::thetTrigLabel

private

Definition at line 115 of file DTTTrigSyncFromDB.h.

double DTTTrigSyncFromDB::theVPropWire

private

Definition at line 103 of file DTTTrigSyncFromDB.h.

int DTTTrigSyncFromDB::theWirePropCorrType

private

Definition at line 111 of file DTTTrigSyncFromDB.h.

const DTTtrig* DTTTrigSyncFromDB::tTrigMap

private

Definition at line 99 of file DTTTrigSyncFromDB.h.

const DTT0* DTTTrigSyncFromDB::tZeroMap

private

Definition at line 98 of file DTTTrigSyncFromDB.h.