Complete:

Contents:

The Trimmed Kalman vertex reconstructor iteratively uses the Trimmed Kalman vertex fitter to find and fit interaction vertices. After each fitted vertex, the remaining tracks are re-used to search for further vertices.

The fitter is implemented in the package RecoVertex/TrimmedKalmanVertexFinder

KalmanTrimmedVertexFinder finder; vector<TransientVertex> vertices = finder.vertices ( vector<TransientTrack> tracks );

To change the parameters, the easiest is to use the

method. Alternatively, individual set methods can be used. The PSet needed is the following:
**setParameters(ParameterSet)**

GSFParameters = cms.PSet( ptCut = cms.double(0.0), vtxFitProbCut = cms.double(0.01), trackCompatibilityToPVcut = cms.double(0.05), trackCompatibilityToSVcut = cms.double(0.01), maxNbOfVertices = cms.int32(0) )

The parameters are the following:

Parameter Name | Description | Default | method |
---|---|---|---|

ptCut | the minimum pT (in GeV) of the tracks used to make vertices. | 1.5 | setPtCut(float) |

trackCompatibilityToPVcut | the probability below which a track is considered incompatible with the 1st vertex candidate formed. | 0.05 | setTrackCompatibilityCut(float) |

trackCompatibilityToSVcut | the probability below which a track is considered incompatible with the next vertex candidates formed. | 0.01 | setTrackCompatibilityToSV(float) |

vertexFitProbabilityCut | the probability below which a vertex is rejected | 0.01 | setVertexFitProbabilityCut(float) |

maxNbOfVertices | the maximum number of vertices searched for. 0 means no limitations | 0 | setMaxNbOfVertices(int) |

-- Main.speer - 05 Jul 2007

This topic: CMSPublic > CMSCommunicationsGroup > CMSCommunicationsProjects > WebHome > SWGuide > SWGuideVertexReco > SWGuideOfflineSecondaryVertexFinding > SWGuideTrimmedKalmanVertexFinder

Topic revision: r2 - 2009-03-11 - ThomasSpeer

Copyright &© 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.

Ideas, requests, problems regarding TWiki? Send feedback

Ideas, requests, problems regarding TWiki? Send feedback