V0.cc

/**************************************************************************
 * 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.                  *
 **************************************************************************/
#include <mdst/dataobjects/V0.h>
 
using namespace Belle2;
using namespace std;
 
V0::V0():
  m_trackIndexPositive(-1),
  m_trackIndexNegative(-1),
  m_trackFitResultIndexPositive(-1),
  m_trackFitResultIndexNegative(-1)
{}
 
V0::V0(const std::pair<const Belle2::Track*, const Belle2::TrackFitResult*>& trackPairPositive,
       const std::pair<const Belle2::Track*, const Belle2::TrackFitResult*>& trackPairNegative) :
  m_trackIndexPositive(trackPairPositive.first->getArrayIndex()),
  m_trackIndexNegative(trackPairNegative.first->getArrayIndex()),
  m_trackFitResultIndexPositive(trackPairPositive.second->getArrayIndex()),
  m_trackFitResultIndexNegative(trackPairNegative.second->getArrayIndex())
{}
 
Const::ParticleType V0::getV0Hypothesis() const
{
  StoreArray<TrackFitResult> trackFitResults{};
  const auto posParticleType = trackFitResults[m_trackFitResultIndexPositive]->getParticleType();
  const auto negParticleType = trackFitResults[m_trackFitResultIndexNegative]->getParticleType();
 
  if ((posParticleType == Const::pion) && (negParticleType == Const::pion)) {
    return Const::Kshort;
  }
  if ((posParticleType == Const::proton) && (negParticleType == Const::pion)) {
    return Const::Lambda;
  }
  if ((posParticleType == Const::pion) && (negParticleType == Const::proton)) {
    return Const::antiLambda;
  }
  if ((posParticleType == Const::electron) && (negParticleType == Const::electron)) {
    return Const::photon;
  }
  return Const::unspecifiedParticle;
}