#include <HIProtoTrackSelector.h>

Public Types
typedef reco::TrackCollection	collection
typedef container::const_iterator	const_iterator
typedef std::vector< const reco::Track * >	container
Public Member Functions
const_iterator	begin () const
const_iterator	end () const
	HIProtoTrackSelector (const edm::ParameterSet &iConfig)
void	select (edm::Handle< reco::TrackCollection > &TCH, const edm::Event &iEvent, const edm::EventSetup &iSetup)
size_t	size () const
Private Attributes
edm::InputTag	beamSpotLabel_
double	maxD0Significance_
double	minZCut_
double	nSigmaZ_
double	ptMin_
container	selected_
edm::InputTag	vertexCollection_

Detailed Description

Selector to select prototracks that pass certain kinematic cuts based on fast vertex

Definition at line 22 of file HIProtoTrackSelector.h.

Member Typedef Documentation

typedef reco::TrackCollection HIProtoTrackSelector::collection

Definition at line 27 of file HIProtoTrackSelector.h.

typedef container::const_iterator HIProtoTrackSelector::const_iterator

Definition at line 33 of file HIProtoTrackSelector.h.

typedef std::vector<const reco::Track *> HIProtoTrackSelector::container

Definition at line 30 of file HIProtoTrackSelector.h.

Constructor & Destructor Documentation

HIProtoTrackSelector::HIProtoTrackSelector ( const edm::ParameterSet & iConfig ) [inline]

Definition at line 36 of file HIProtoTrackSelector.h.

                                                        : 
    vertexCollection_(iConfig.getParameter<edm::InputTag>("VertexCollection")),
    beamSpotLabel_(iConfig.getParameter<edm::InputTag>("beamSpotLabel")),
    ptMin_(iConfig.getParameter<double>("ptMin")),      
    nSigmaZ_(iConfig.getParameter<double>("nSigmaZ")),
    minZCut_(iConfig.getParameter<double>("minZCut")),
    maxD0Significance_(iConfig.getParameter<double>("maxD0Significance"))
    {};

Member Function Documentation

const_iterator HIProtoTrackSelector::begin ( void ) const [inline]

Definition at line 119 of file HIProtoTrackSelector.h.

References selected_.

{ return selected_.begin(); }

const_iterator HIProtoTrackSelector::end ( void ) const [inline]

Definition at line 122 of file HIProtoTrackSelector.h.

References selected_.

{ return selected_.end(); }

void HIProtoTrackSelector::select	(	edm::Handle< reco::TrackCollection > &	TCH,
		const edm::Event &	iEvent,
		const edm::EventSetup &	iSetup
	)		`[inline]`

Definition at line 46 of file HIProtoTrackSelector.h.

References beamSpotLabel_, reco::BeamSpot::BeamWidthX(), reco::BeamSpot::BeamWidthY(), trackerHits::c, debug_cff::d0, edm::Event::getByLabel(), edm::HandleBase::isValid(), max(), maxD0Significance_, minZCut_, nSigmaZ_, reco::BeamSpot::position(), edm::Handle< T >::product(), ptMin_, selected_, mathSSE::sqrt(), and vertexCollection_.

    {
      selected_.clear();
      
      const collection & c = *(TCH.product());
      
      // Get fast reco vertex 
      edm::Handle<reco::VertexCollection> vc;
      iEvent.getByLabel(vertexCollection_, vc);
      const reco::VertexCollection * vertices = vc.product();
      
      math::XYZPoint vtxPoint(0.0,0.0,0.0);
      double vzErr =0.0;
      
      if(vertices->size()>0) {
        vtxPoint=vertices->begin()->position();
        vzErr=vertices->begin()->zError();
        edm::LogInfo("HeavyIonVertexing") << "Select prototracks compatible with median vertex"
                                     << "\n   vz = " << vtxPoint.Z()  
                                     << "\n   " << nSigmaZ_ << " vz sigmas = " << vzErr*nSigmaZ_
                                     << "\n   cut at = " << std::max(vzErr*nSigmaZ_,minZCut_);
      } else {
        edm::LogError("HeavyIonVertexing") << "No vertex found in collection '" << vertexCollection_ << "'";
      }
      
      // Get beamspot
      reco::BeamSpot beamSpot;
      edm::Handle<reco::BeamSpot> beamSpotHandle;
      iEvent.getByLabel(beamSpotLabel_, beamSpotHandle);
      
      math::XYZPoint bsPoint(0.0,0.0,0.0);
      double bsWidth = 0.0;
      
      if ( beamSpotHandle.isValid() ) {
        beamSpot = *beamSpotHandle;
        bsPoint = beamSpot.position();
        bsWidth = sqrt(beamSpot.BeamWidthX()*beamSpot.BeamWidthY());
        edm::LogInfo("HeavyIonVertexing") << "Select prototracks compatible with beamspot"
                                     << "\n   (x,y,z) = (" << bsPoint.X() << "," << bsPoint.Y() << "," << bsPoint.Z() << ")"  
                                     << "\n   width = " << bsWidth
                                     << "\n   cut at d0/d0sigma = " << maxD0Significance_;
      } else {
        edm::LogError("HeavyIonVertexing") << "No beam spot available from '" << beamSpotLabel_ << "\n";
      }
      
      
      // Do selection
      int nSelected=0;
      int nRejected=0;
      double d0=0.0; 
      double d0sigma=0.0;
      for (reco::TrackCollection::const_iterator trk = c.begin(); trk != c.end(); ++ trk)
        {
          
          d0 = -1.*trk->dxy(bsPoint);
          d0sigma = sqrt(trk->d0Error()*trk->d0Error() + bsWidth*bsWidth);
          if ( trk->pt() > ptMin_ // keep only tracks above ptMin
               && fabs(d0/d0sigma) < maxD0Significance_ // keep only tracks with D0 significance less than cut
               && fabs(trk->dz(vtxPoint)) <  std::max(vzErr*nSigmaZ_,minZCut_) // within minZCut, nSigmaZ of fast vertex
               ) 
          {
            nSelected++;
            selected_.push_back( & * trk );
          } 
          else 
            nRejected++;
        }
      
      edm::LogInfo("HeavyIonVertexing") << "selected " << nSelected << " prototracks out of " << nRejected+nSelected << "\n";
      
    }