/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.28/xAODBPhys/xAODBPhys/BPhysHelper.h File Reference

: B-physcis xAOD helpers. More...

#include "xAODTracking/TrackParticleFwd.h"
#include "xAODTracking/VertexFwd.h"
#include "xAODTracking/VertexContainerFwd.h"
#include "xAODMuon/MuonContainer.h"
#include "TVector3.h"
#include "TLorentzVector.h"
#include "TMatrixTSym.h"
#include <assert.h>

Go to the source code of this file.

Classes
class	xAOD::BPhysHelper
Namespaces
namespace	xAOD
	Namespace holding all the xAOD EDM classes.
Defines
#define	BPHYS_CHECK(EXP)   { if( ! EXP ) ATH_MSG_WARNING ( "Call of \"" << #EXP << "\" failed" ); }

---

Detailed Description

: B-physcis xAOD helpers.

Author:

: Daniel Scheirich <daniel.scheirich@cern.ch>

This class provides interface to the basic B-physics augmemtation of the xAOD::Vertex, i.e.:

• refitted track momenta
• links to muons
• links to other vertices
• links to (some) refitted PV
• transverse distance (and errors)
• impact parameters (and errors)
• pT error

In addition, it provides methods that convert covariance matrix from its native xAOD form (i.e. vector<float>) into the matrix form represented by the TMatrixTSym<double> class

To access hypothesis-specific augmentation (e.g. invariant mass, lifetime, etc) use BPhysHypoHelper.

Note:

The class caches covariance matrix, refitted track momenta, pointers to muons and pointers to other vertices in order to speed up access when getter methods are called repeatedly

Usage example:

    void myFunction(xAOD::Vertex* vtx) {
      // Let "vtx" be some xAOD::Vertex created by the b-physics software
      // We gain access to augmentations through the helper class:
      xAOD::BPhysHelper bVtx(vtx);

      std::cout << "Refitted pT of the 1st track: ";
      if(bVtx.nRefTrks()>0) {
        std::cout <<  bVtx.refTrk(0).Pt();
      }
      std::cout << std::endl;

    }

---

Define Documentation

#define BPHYS_CHECK

(

EXP

)

{ if( ! EXP ) ATH_MSG_WARNING ( "Call of \"" << #EXP << "\" failed" ); }

Useful CHECK macro