HGCalTriggerCellCalibration.cc

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#include "L1Trigger/L1THGCal/interface/veryfrontend/HGCalTriggerCellCalibration.h"

//class constructor
HGCalTriggerCellCalibration::HGCalTriggerCellCalibration(const edm::ParameterSet& conf)
    : LSB_silicon_fC_(conf.getParameter<double>("siliconCellLSB_fC")),
      LSB_scintillator_MIP_(conf.getParameter<double>("scintillatorCellLSB_MIP")),
      fCperMIP_(conf.getParameter<double>("fCperMIP")),
      thickCorr_(conf.getParameter<double>("thickCorr")),
      dEdX_weights_(conf.getParameter<std::vector<double>>("dEdXweights")) {
  if (fCperMIP_ <= 0) {
    edm::LogWarning("DivisionByZero") << "WARNING: the MIP->fC correction factor is zero or negative. It won't be "
                                         "applied to correct trigger cell energies.";
  }
  if (thickCorr_ <= 0) {
    edm::LogWarning("DivisionByZero") << "WARNING: the cell-thickness correction factor is zero or negative. It won't "
                                         "be applied to correct trigger cell energies.";
  }
}

void HGCalTriggerCellCalibration::calibrateInMipT(l1t::HGCalTriggerCell& trgCell) {
  bool isSilicon = triggerTools_.isSilicon(trgCell.detId());

  /* get the hardware pT in ADC counts: */
  int hwPt = trgCell.hwPt();

  // Convert ADC to charge in fC (in EE+FH) or in MIPs (in BH)
  double amplitude = hwPt * (!isSilicon ? LSB_scintillator_MIP_ : LSB_silicon_fC_);

  // The responses of the different cell thicknesses have been equalized
  // to the 200um response in the front-end. So there is only one global
  // fCperMIP and thickCorr here
  /* convert the charge amplitude in MIP: */
  double trgCellMipP = amplitude;
  if (isSilicon && fCperMIP_ > 0) {
    trgCellMipP /= fCperMIP_;
  }

  /* compute the transverse-mip */
  double trgCellMipPt = trgCellMipP / cosh(trgCell.eta());

  /* setting pT [mip] */
  trgCell.setMipPt(trgCellMipPt);
}

void HGCalTriggerCellCalibration::calibrateMipTinGeV(l1t::HGCalTriggerCell& trgCell) {
  const double MevToGeV(0.001);

  DetId trgdetid(trgCell.detId());
  unsigned trgCellLayer = triggerTools_.layerWithOffset(trgdetid);

  if (dEdX_weights_.at(trgCellLayer) == 0.) {
    throw cms::Exception("BadConfiguration")
        << "Trigger cell energy forced to 0 by calibration coefficients.\n"
        << "The configuration should be changed. "
        << "Discarded layers should be defined in hgcalTriggerGeometryESProducer.TriggerGeometry.DisconnectedLayers "
           "and not with calibration coefficients = 0\n";
  }

  /* weight the amplitude by the absorber coefficient in MeV/mip + bring it in GeV */
  double trgCellEt = trgCell.mipPt() * dEdX_weights_.at(trgCellLayer) * MevToGeV;

  /* correct for the cell-thickness */
  if (triggerTools_.isSilicon(trgdetid) && thickCorr_ > 0) {
    trgCellEt /= thickCorr_;
  }
  /* assign the new energy to the four-vector of the trigger cell */
  math::PtEtaPhiMLorentzVector calibP4(trgCellEt, trgCell.eta(), trgCell.phi(), 0.);

  /* overwriting the 4p with the calibrated 4p */
  trgCell.setP4(calibP4);
}

void HGCalTriggerCellCalibration::calibrateInGeV(l1t::HGCalTriggerCell& trgCell) {
  /* calibrate from ADC count to transverse mip */
  calibrateInMipT(trgCell);

  /* calibrate from mip count to GeV */
  calibrateMipTinGeV(trgCell);
}