Tracker Numbering Builder

All the CmsTracker…Builder='s inherit from =CmsTrackerLevelBuilder. It looks like a tree of classes is created and their method build is called to sort and assign the detids to the different modules. The branching is done by converting a string from DDD to an enum and by deciding which CmsTracker…Builder to call. The hierarchy is:

• CmsTrackerBuilder
  • CmsTrackerSubStrctBuilder
    • CmsTrackerLayerBuilder
      • CmsTrackerStringBuilder
      • CmsTrackerRodBuilder
      • CmsTrackerLadderBuilder
    • CmsTrackerWheelBuilder
      • CmsTrackerRingBuilder
      • CmsTrackerPetalBuilder
    • CmsTrackerDiskBuilder
      • CmsTrackerPanelBuilder

For the phase 2 upgrade it should be possible to define another builder for the outer tracker disks to be called by CmsTrackerDiskBuilder to build properly the Outer Tracker disks

Track Refitting

Comments (based on 3_9_5)

The TrackRefitter, as any TrackProducerBase, needs many ES objects. One of the is the TrajectoryFitter, through the TrajectoryFitterRecord. The name of the TrajectoryFitter is the parameter Fitter of the configuration. In RecoTracker.TrackProducer.TrackRefitter_cfi the fitter is KFFittingSmootherWithOutliersRejectionAndRK.

module	ESProducer	name	fitter	smoother
KFFittingSmoother	KFFittingSmootherESProducer	KFFittingSmoother	KFFitter	KFSmoother
MRHFittingSmoother	KFFittingSmootherESProducer	MRHFittingSmoother	MRHFitter	MRHSmoother
RK1DFittingSmoother	KFFittingSmootherESProducer	RK1DFittingSmoother	RK1DFitter	RK1DSmoother
RKOutliers1DFittingSmoother	KFFittingSmootherESProducer	RKOutliers1DFittingSmoother	RK1DFitter	RK1DSmoother
RKFittingSmoother	KFFittingSmootherESProducer	RKFittingSmoother	RKFitter	RKSmoother
KFFittingSmootherWithOutliersRejectionAndRK	KFFittingSmootherESProducer	KFFittingSmootherWithOutliersRejectionAndRK	RKFitter	RKSmoother

module	ESProducer	name	propagator	updator	estimator
KFTrajectoryFitter	KFTrajectoryFitterESProducer	KFFitter	PropagatorWithMaterial	KFUpdator	Chi2
MRHTrajectoryFitter	KFTrajectoryFitterESProducer	MRHFitter	RungeKuttaTrackerPropagator	KFUpdator	MRHChi2
RK1DTrajectoryFitter	KFTrajectoryFitterESProducer	RK1DFitter	RungeKuttaTrackerPropagator	KFSwitching1DUpdator	Chi2
RKTrajectoryFitter	KFTrajectoryFitterESProducer	RKFitter	RungeKuttaTrackerPropagator	KFUpdator	Chi2

module	ESProducer	name	propagator	updator	estimator
KFTrajectorySmoother	KFTrajectorySmootherESProducer	KFSmoother	PropagatorWithMaterial	KFUpdator	Chi2
MRHTrajectorySmoother	KFTrajectorySmootherESProducer	MRHSmoother	RungeKuttaTrackerPropagator	KFUpdator	MRHChi2
RK1DTrajectorySmoother	KFTrajectorySmootherESProducer	RK1DSmoother	RungeKuttaTrackerPropagator	KFSwitching1DUpdator	Chi2
RKTrajectorySmoother	KFTrajectorySmootherESProducer	RKSmoother	RungeKuttaTrackerPropagator	KFUpdator	Chi2

Configuration

The configuration file to be used when tracks have to be refitted is: RecoTracker.TrackProducer.TrackRefitters_cff

Trajectories, Tracks and TSOS

• Useful hn message

TSOS

• Example to convert a PTrajectoryStateOnDet to a TSOS

How to get a TrajectoryStateClosestToBeamLine

• TSCBLBuilderWithPropagator

Seeding

Iteration Configurations

• pixelTracks: RecoPixelVertexing/ PixelTrackFitting/ python/ PixelTrackReconstruction_cfi.py

• newSeedFromTriplets: RecoTracker/ IterativeTracking/ python/ FirstStep_cff.py
• newSeedFromPairs: RecoTracker/ IterativeTracking/ python/ FirstStep_cff.py
• secTriplets: RecoTracker/ IterativeTracking/ python/ SecStep_cff.py
• thTripletsA: RecoTracker/ IterativeTracking/ python/ ThStep_cff.py
• thTripletsB: RecoTracker/ IterativeTracking/ python/ ThStep_cff.py
• fourthPLSeeds: RecoTracker/ IterativeTracking/ python/PixelLessStep_cff.py
• fifthSeeds: RecoTracker/ IterativeTracking/ python/ TobTecStep_cff.py

Seeding algorithm

Common Tools

There are:

• Seeding with triplets:
  • globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer. The EDProducer class is SeedGeneratorFromRegionHitsEDProducer. It contains:
    • a TrackingRegionProducerFactory
    • theGenerator which is a SeedGeneratorFromRegionHits
      • it is configured with a theHitsGenerator, aComaparitor and aCreator
      • for each region theHitsGenerator "run" is executed
      • when theHitsGenerator is a CombinedHitTripletGenerator (plugin is called StandardHitTripletGenerator):
        • theGenerators collection is filled with one HitTripletGeneratorFromPairandLayers for each seeding layer combination
          • a seeding layer combination is made of a pair of layers plus all the other third layers
        • "hitsTriplets" is called and for each element of theGenerators
          • it is in each element of theGenerators that the "TooManyTriplets" threshold is applied. If passed all the OrderedHitTriplets produced so far are deleted and only the remaning seeding layer combinations can contribute
          • the number of seed threshold is in OrderedHitsFactoryPSet.GeneratorPSet.maxElement

• Seeding with pairs:
  • globalSeedsFromPairsWithVertices which is cloned from seedGeneratorFromRegionHitsEDProducer and:
    • it uses the plugin StandardHitPairGenerator which corresponds to the class CombinedHitPairGenerator. For each combination of seeding layers a HitPairGeneratorFromLayerPair is created. The number of seed threshold is in OrderedHitsFactoryPSet.maxElement. This threshold is applied to each seeding layer pairs. This means that the total number of seeds can exceed this threshold.
    • it uses GlobalTrackingRegionFromVerticesProducer
  • globalMixedSeeds which is cloned from seedGeneratorFromRegionHitsEDProducer and:
    • it uses the plugin StandardHitPairGenerator (see above) and the number of seed threshold is in OrderedHitsFactoryPSet.maxElement
    • it uses GlobalTrackingRegionFromBeamSpot

Different iteration configurations

pixelTracks

In 39x:

• It uses PixelTrackProducer which:
  • uses StandardHitTripletGenerator as OrderedHitFactory

newSeedFromTriplets (0th step)

In 39x:

• cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it uses StandardHitTripletGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.GeneratorPSet.maxElement
  • PixelTripletHLTGenerator used as seed generator (inherits from HitTripletGeneratorFromPairAndLayers)
  • it uses as SeedComparitor LowPtClusterShapeSeedComparitor

newSeedFromPairs (1st step)

In 39x:

• cloned from globalSeedsFromPairsWithVertices which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it used StandardHitPairGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.maxElement

secTriplets (2nd step)

In 39x

• cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it uses StandardHitTripletGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.GeneratorPSet.maxElement
  • PixelTripletHLTGenerator used as seed generator (inherits from HitTripletGeneratorFromPairAndLayers)
  • it uses as SeedComparitor LowPtClusterShapeSeedComparitor

thTripletsA (3rd step)

In 39x

• cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it uses GlobalRegionProducerFromBeamSpot
  • it uses StandardHitTripletGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.GeneratorPSet.maxElement
  • PixelTripletLargeTipGenerator used as seed generator (inherits from HitTripletGeneratorFromPairAndLayers)
  • no SeedComparitor

thTripletsB (3rd step)

In 39x

• cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it uses GlobalRegionProducerFromBeamSpot
  • it uses StandardHitTripletGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.GeneratorPSet.maxElement
  • PixelTripletLargeTipGenerator used as seed generator (inherits from HitTripletGeneratorFromPairAndLayers)
  • no SeedComparitor

fourthPLSeeds (4th step)

In 39x

• cloned from globalMixedSeeds which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it used StandardHitPairGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.maxElement

fifthSeeds (5th step)

In 39x

• cloned from globalMixedSeeds which is cloned from seedGeneratorFromRegionHitsEDProducer and:
  • it used StandardHitPairGenerator and the number of seed threshold is in OrderedHitsFactoryPSet.maxElement

How to set threshold on the total number of OrderedHitTriplets (seed candidates)

process.newSeedFromTriplets.OrderedHitsFactoryPSet.GeneratorPSet.maxElement = cms.uint32(100000) process.newSeedFromPairs.OrderedHitsFactoryPSet.maxElement = cms.uint32(100000) process.secTriplets.OrderedHitsFactoryPSet.GeneratorPSet.maxElement = cms.uint32(100000) process.thTripletsA.OrderedHitsFactoryPSet.GeneratorPSet.maxElement = cms.uint32(100000) process.thTripletsB.OrderedHitsFactoryPSet.GeneratorPSet.maxElement = cms.uint32(100000) process.fourthPLSeeds.OrderedHitsFactoryPSet.maxElement = cms.uint32(100000) process.fifthSeeds.OrderedHitsFactoryPSet.maxElement = cms.uint32(100000)

process.pixelTracks.OrderedHitsFactoryPSet.GeneratorPSet.maxElement = cms.uint32(100000)

Global Tracking Region configurations

General Tools

Parameters and and algorithm are defined in RegionFactoryPSet and in RegionFactoryPSet.RegionPSet Deafult parameter blocks can be found in:

• RecoTracker/ TkTrackingRegions/ python/ GlobalTrackingRegionFromBeamSpot_cfi.py
  • RegionPsetFromBeamSpotBlock: 3sigmaZ
  • RegionPsetFromBeamSpotBlockFixedZ available: 15.9 cm
• RecoTracker/ TkTrackingRegions/ python/ GlobalTrackingRegion_cfi.py
• RecoTracker/ TkTrackingRegions/ python/ GlobalTrackingRegionWithVertices_cfi.py
  • RegionPSetWithVerticesBlock

Different iteration configurations

pixelTracks

RecoPixelVertexing/ PixelTrackFitting/ python/ PixelTrackReconstruction_cfi.py In 39x:

• default
  • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlock : 3 sigmaZ
• TLR
  • process.pixelTracks.RegionFactoryPSet.RegionPSet.nSigmaZ  = 4.06
  • process.pixelTracks.RegionFactoryPSet.RegionPSet.originHalfLength = cms.double(40.6)

newSeedFromTriplets (0th step)

RecoTracker/ IterativeTracking/ python/ FirstStep_cff.py In 42x:

• default
  • cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • pt cut modified to 0.8 GeV
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlock : 3 sigmaZ

newSeedFromPairs (1st step)

RecoTracker/ IterativeTracking/ python/ FirstStep_cff.py In 42x:

• default
  • cloned from globalSeedsFromPairsWithVertices which is cloned from seedGeneratorFromRegionHitsEDProducer
  • pt cut modified to 0.6 GeV, originRadius modified to 0.05
  • GlobalTrackingRegionFromVerticesProducer + RegionPSetWithVerticesBlock: 0.2 mm around the vertices

secTriplets (2nd step)

RecoTracker/ IterativeTracking/ python/ SecStep_cff.py In 42x

• default
  • cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlock +
    • pt cut modified to 0.075 GeV, originHalfLength = 3.3 sigmaZ

thTripletsA (3rd step)

RecoTracker/ IterativeTracking/ python/ ThStep_cff.py In 42x

• default
  • cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlockFixedZ +
    • pt cut modified to 0.25 GeV, originHalfLength = 10cm, originRadius = 2cm

thTripletsB (3rd step)

RecoTracker/ IterativeTracking/ python/ ThStep_cff.py In 39x

• default
  • cloned from globalSeedsFromTriplets which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlockFixedZ +
    • pt cut modified to 0.35 GeV, originHalfLength = 10cm, originRadius = 2cm

fourthPLSeeds (4th step)

RecoTracker/ IterativeTracking/ python/PixelLessStep_cff.py In 39x

• default
  • cloned from globalMixedSeeds which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlockFixedZ +
    • pt cut modified to 0.5 GeV, originHalfLength = 12cm, originRadius = 2cm

fifthSeeds (5th step)

RecoTracker/ IterativeTracking/ python/ TobTecStep_cff.py In 39x

• default
  • cloned from globalMixedSeeds which is cloned from seedGeneratorFromRegionHitsEDProducer:
    • GlobalRegionProducerFromBeamSpot + RegionPsetFromBeamSpotBlockFixedZ +
    • pt cut modified to 0.6 GeV, originHalfLength = 30cm, originRadius = 6cm

Tracking anf HLT

Pixel Tracks

The differences between pixelTracks and hltPixelTracks are (2011/05/29):

• OrderedHitsFactoryPSet.GeneratorPSet.maxElement = 100k offline and 10k at HLT
• OrderedHitsFactoryPSet.GeneratorPSet.extraHitRPhitolerance = 0.032 offline and 0.06 at HLT
• OrderedHitsFactoryPSet.GeneratorPSet.extraHitRZtolerance = 0.037 offline and 0.06 at HLT
• FitterPSet.TTRHBuilder = hltESPTTRHBuilderPixelOnly at HLT and PixelTTRHBuilderWithoutAngle offline but they are identical (I hope...)
• Global tracking region with +/-3sigmaZ acceptance offline and +/-24cm acceptace at HLT

-- AndreaVenturi - 04-Sep-2010