DriftLengthEstimator.h

/**************************************************************************
 * basf2 (Belle II Analysis Software Framework)                           *
 * Author: The Belle II Collaboration                                     *
 *                                                                        *
 * See git log for contributors and copyright holders.                    *
 * This file is licensed under LGPL-3.0, see LICENSE.md.                  *
 **************************************************************************/
#pragma once
 
#include <cdc/translators/RealisticTDCCountTranslator.h>
 
#include <tracking/trackingUtilities/geometry/UncertainParameterLine2D.h>
 
#include <memory>
#include <string>
#include <cmath>
 
namespace Belle2 {
  class ModuleParamList;
}
 
namespace Belle2 {
  namespace TrackingUtilities {
    class CDCTrack;
    class CDCRecoHit3D;
    class CDCRecoHit2D;
    class CDCFacet;
    class CDCSegment2D;
    class CDCSegment3D;
  }
  namespace TrackFindingCDC {

    struct DriftLengthEstimator {

      void exposeParameters(ModuleParamList* moduleParamList, const std::string& prefix);

      double updateDriftLength(TrackingUtilities::CDCRecoHit2D& recoHit2D);

      double updateDriftLength(TrackingUtilities::CDCRecoHit3D& recoHit3D, double tanLambda);

      void updateDriftLength(TrackingUtilities::CDCFacet& facet);

      struct FacetDriftLengthCache {
        bool valid = false;

        TrackingUtilities::UncertainParameterLine2D fitLine;

        double alpha = 0;

        double middleFlightTime = 0;

        double startDriftLength = 0;

        double endDriftLength = 0;
      };

      void updateDriftLength(TrackingUtilities::CDCFacet& facet, FacetDriftLengthCache& cache);

      void updateDriftLength(TrackingUtilities::CDCSegment2D& segment);

      void updateDriftLength(TrackingUtilities::CDCSegment3D& segment, double tanLambda);

      void updateDriftLength(TrackingUtilities::CDCTrack& track, double tanLambda);

      bool m_param_useAlphaInDriftLength = true;

      double m_param_tofMassScale = NAN;
 
    private:
      CDC::RealisticTDCCountTranslator& getTDCCountTranslator()
      {
        if (not m_tdcCountTranslator) {
          m_tdcCountTranslator = std::make_shared<CDC::RealisticTDCCountTranslator>();
        }
        return *m_tdcCountTranslator;
      }

      std::shared_ptr<CDC::RealisticTDCCountTranslator> m_tdcCountTranslator;
    };
  }
}