RecoilMassConstraint.h

/**************************************************************************
 * BASF2 (Belle Analysis Framework 2)                                     *
 * Copyright(C) 2017 - Belle II Collaboration                             *
 *                                                                        *
 * RecoilMassConstraint for OrcaKinFit. Allows constraints of the type    *
 * mass(P_beam - P) - RecoilMass = 0s                                      *
 *                                                                        *
 * Author: The Belle II Collaboration                                     *
 * Contributors: Torben Ferber (torben.ferber@desy.de) (TF)               *
 *                                                                        *
 * This software is provided "as is" without any warranty.                *
 **************************************************************************/
 
#ifndef __RECOILMASSCONSTRAINT_H
#define __RECOILMASSCONSTRAINT_H
 
#include "analysis/OrcaKinFit/ParticleConstraint.h"
 
namespace Belle2 {
  namespace OrcaKinFit {
 
    class ParticleFitObject;
 
    class RecoilMassConstraint : public ParticleConstraint {
    public:
 
      RecoilMassConstraint(double recoilmass = 0., double beampx = 0., double beampy = 0., double beampz = 0, double beampe = 0.);
 
      virtual ~RecoilMassConstraint();
 
      virtual double getValue() const override;
 
      virtual void getDerivatives(int idim,      
                                  double der[]   
                                 ) const override;
 
      virtual double getRecoilMass();
 
      virtual void setRecoilMass(double recoilmass);
 
      virtual int getVarBasis() const override;
 
    protected:
 
      double m_recoilMass;
      double m_beamPx;
      double m_beamPy;
      double m_beamPz;
      double m_beamE;
 
      virtual bool secondDerivatives(int i,                         
                                     int j,                        
                                     double* derivatives           
                                    ) const override;
 
      virtual bool firstDerivatives(int i,                         
                                    double* derivatives           
                                   ) const override;
 
      enum { VAR_BASIS = 0 }; // this means that the constraint knows about E,px,py,pz
 
    };
 
  }// end OrcaKinFit namespace
} // end Belle2 namespace
 
#endif // __RECOILMASSCONSTRAINT_H