InitialParticleGeneration.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 <framework/datastore/StoreObjPtr.h>
#include <framework/database/DBObjPtr.h>
#include <framework/utilities/MultivariateNormalGenerator.h>
#include <framework/dbobjects/BeamParameters.h>
#include <framework/dataobjects/MCInitialParticles.h>
 
#include <framework/utilities/ConditionalGaussGenerator.h>
 
#include <TMatrixDSym.h>
 
namespace Belle2 {
  class InitialParticleGeneration {
  public:
    explicit InitialParticleGeneration(int allowedFlags = 0): m_allowedFlags(allowedFlags | MCInitialParticles::c_generateCMS) {};
 
    MCInitialParticles& generate();
 
    ROOT::Math::XYZVector getVertexConditional();
 
    ROOT::Math::XYZVector updateVertex(bool force = false);
 
    const BeamParameters& getBeamParameters() const { return *m_beamParams; }
 
    void initialize();
 
    void setAllowedFlags(int allowedFlags)
    {
      m_allowedFlags = allowedFlags | MCInitialParticles::c_generateCMS;
    }
 
    ConditionalGaussGenerator initConditionalGenerator(const ROOT::Math::PxPyPzEVector& pHER,  const ROOT::Math::PxPyPzEVector& pLER,
                                                       const TMatrixDSym& covHER, const TMatrixDSym& covLER);
 
    double getNominalEcms()       { return m_beamParams->getMass(); }
 
    double getNominalEcmsSpread() { return  m_generateLorentzTransformation.getX0spread(); }
 
    const ConditionalGaussGenerator& getLorentzGenerator() { return m_generateLorentzTransformation; }
 
  private:
 
    MCInitialParticles& generate(int allowedFlags);
 
    TMatrixDSym adjustCovMatrix(TMatrixDSym cov) const;
 
 
    ROOT::Math::XYZVector generateVertex(const ROOT::Math::XYZVector& initial, const TMatrixDSym& cov,
                                         MultivariateNormalGenerator& gen) const;
    ROOT::Math::PxPyPzEVector generateBeam(const ROOT::Math::PxPyPzEVector& initial, const TMatrixDSym& cov,
                                           MultivariateNormalGenerator& gen) const;
    DBObjPtr<BeamParameters> m_beamParams;
    StoreObjPtr<MCInitialParticles> m_event;
    MultivariateNormalGenerator m_generateHER;
    MultivariateNormalGenerator m_generateLER;
    MultivariateNormalGenerator m_generateVertex;
 
    ConditionalGaussGenerator m_generateLorentzTransformation;
 
    int m_allowedFlags;
  };
 
 
} //Belle2 namespace