Samples with full event information including tracker hits for tracking, ML, and top quark tagging studies

Description

Samples in this record are in a custom root ntuple format and contain the position of the hits and information from the generator-level objects associated to the tracker hits. The samples can be used to study top quark identification algorithms that use low-level detector information such as tracker hits. Machine learning algorithms are suitable for this classification task.

They have been produced from datasets, which consists of events extracted from simulated proton-proton collision events at a center-of-mass energy of 8 TeV generated with Pythia 6 (QCD) or MadGraph2.6 and Pythia6 (top-antitop pair sample). The particles emerging from the collisions traverse through a simulation of the CMS detector.

The parent datasets of these samples contain light jets (QCD) in various energy ranges or all-hadronic high transverse momentum decays of top quarks and consist of hits from the tracking detector, reconstructed tracks, simulated tracks, generated particles, and jets clustered from the generated particles. The various objects are matched in order to reconstruct the provenance of the various hits. Samples are produced from the standard CMS format "AODSIM" plus a series of low-level tracker-related collections that allow the extraction of the tracker hits.

Data set name	Description	Number of events	Number of files
QCD300to600	QCD, flat pT hat spectrum, 300 < pT hat < 600 GeV	1497600	2496
QCD400to600	QCD, flat pT hat spectrum, 400 < pT hat < 600 GeV	1989000	3315
QCD600to3000	QCD, flat pT hat spectrum, 600 < pT hat < 3000 GeV	2974800	4959
ttbar	ttbar, fully hadronic decays, pT of the top/antitop greater than 400 GeV	2969109	4055

Related datasets

QCD300to600_RunI_8TeV was derived from:

Tracker-hit-enriched 300 to 600 bin of QCD_Pt-15to3000_TuneZ2star_Flat_8TeV_pythia6

QCD400to600_RunI_8TeV was derived from:

Tracker-hit-enriched 400 to 600 bin of QCD_Pt-15to3000_TuneZ2star_Flat_8TeV_pythia6

QCD600to3000_RunI_8TeV was derived from:

Tracker-hit-enriched 600 to 3000 bin of QCD_Pt-15to3000_TuneZ2star_Flat_8TeV_pythia6

ttbar_RunI_8TeV was derived from:

Tracker-hit-enriched TTJets_HadronicMGDecays_8TeV-madgraph

Dataset characteristics

9430509 events. 14825 files. 11.7 TiB in total.

Dataset semantics

Variable	Type	Description
hit_global_x	std::vector<float>	global x position of the RecHit
hit_global_y	std::vector<float>	global y position of the RecHit
hit_global_z	std::vector<float>	global z position of the RecHit
hit_local_x	std::vector<float>	x pos. of the hit in the local sensor coordinate
hit_local_y	std::vector<float>	y pos. of the hit in the local sensor coordinate
hit_local_x_error	std::vector<float>	x error in the local sensor coordinate
hit_local_y_error	std::vector<float>	y error in the local sensor coordinate
hit_sub_det	std::vector<unsigned int>	subdetector generating the hit [1 PixelBarrel, 2 PixelEndcap, 3 TIB, 4 TID, 5 TOB, 6 TEC]
hit_layer	std::vector<unsigned int>	layer/disk of the subdetector generating the hit
hit_type	std::vector<unsigned int>	type of sistrip hit [0 Pixel hit, 1 rphiRecHit, 2 stereoRecHit, 3 rphiRecHitUnmatched, 4 stereoRecHitUnmatched]
hit_simtrack_id	std::vector<int>	ID number of the sim track matched to the hit
hit_simtrack_index	std::vector<unsigned int>	index of the sim track matched to the hit
hit_simtrack_match	std::vector<bool>	is the hit matched to a sim track?
hit_genparticle_id	std::vector<unsigned int>	index of the gen particle matched to the hit
hit_pdgid	std::vector<int>	PDG ID of the gen particle matched to the hit
hit_recotrack_id	std::vector<unsigned int>	index of the reco track matched to the hit
hit_recotrack_match	std::vector<bool>	is the hit matched to a reco track?
hit_genparticle_match	std::vector<bool>	is the hit matched to a gen particle?
hit_genjet_id	std::vector<unsigned int>	index of the gen jet matched to the hit
hit_genjet_match	std::vector<bool>	is the hit matched to a gen jet?
simtrack_id	std::vector<unsigned int>	ID number of the sim track
simtrack_pdgid	std::vector<int>	PDG ID of the sim track
simtrack_charge	std::vector<int>	charge of the sim track
simtrack_px	std::vector<float>	momentum x component of the sim track
simtrack_py	std::vector<float>	momentum y component of the sim track
simtrack_pz	std::vector<float>	momentum z component of the sim track
simtrack_energy	std::vector<float>	energy of the sim track
simtrack_vtxid	std::vector<unsigned int>	ID number of the sim vertex of the sim track
simtrack_genid	std::vector<unsigned int>	index of the gen particle associated to the track
simtrack_evtid	std::vector<uint32_t>	event ID of the sim track
genpart_collid	std::vector<int>	collision ID of the gen particle
genpart_pdgid	std::vector<int>	PDG ID of the gen particle
genpart_charge	std::vector<int>	charge of the gen particle
genpart_px	std::vector<float>	momentum x component of the gen particle
genpart_py	std::vector<float>	momentum y component of the gen particle
genpart_px	std::vector<float>	momentum z component of the gen particle
genpart_energy	std::vector<float>	energy of the gen particle
genpart_status	std::vector<int>	PDG status of the gen particle
genjet_px	std::vector<float>	momentum x component of the gen jet
genjet_py	std::vector<float>	momentum y component of the gen jet
genjet_pz	std::vector<float>	momentum z component of the gen jet
genjet_energy	std::vector<float>	energy of the gen jet
genjet_emEnergy	std::vector<float>	electromagnetic energy of the gen jet
genjet_hadEnergy	std::vector<float>	hadronic energy of the gen jet
genjet_invisibleEnergy	std::vector<float>	invisible energy of the gen jet
genjet_auxiliaryEnergy	std::vector<float>	auxiliary energy of the gen jet
genjet_const_collid	std::vector<std::vector<int> >	collision ID of the constituent of the gen jet
genjet_const_pdgid	std::vector<std::vector<int> >	PDG ID of the constituent of the gen jet
genjet_const_charge	std::vector<std::vector<int> >	charge of the constituent of the gen jet
genjet_const_px	std::vector<std::vector<float> >	momentum x component of the constituent of the gen jet
genjet_const_py	std::vector<std::vector<float> >	momentum y component of the constituent of the gen jet
genjet_const_pz	std::vector<std::vector<float> >	momentum z component of the constituent of the gen jet
genjet_const_energy	std::vector<std::vector<float> >	energy of the constituent of the gen jet
track_chi2	std::vector<float>	chi2 of the reco track fit
track_ndof	std::vector<float>	ndof of the reco track fit
track_chi2ndof	std::vector<float>	reduced chi2 of the reco track fit
track_charge	std::vector<float>	charge of the reco track
track_momentum	std::vector<float>	momentum of the reco track
track_pt	std::vector<float>	transverse momentum of the reco track
track_pterr	std::vector<float>	error on the transverse momentum of the reco track
track_hitsvalid	std::vector<unsigned int>	number of valid hits in the reco track
track_hitslost	std::vector<unsigned int>	number of lost hits in the reco track
track_theta	std::vector<float>	theta angle of the reco track
track_thetaerr	std::vector<float>	error on theta of the reco track
track_phi	std::vector<float>	phi angle of the reco track
track_phierr	std::vector<float>	error on phi of the reco track
track_eta	std::vector<float>	pseudorapidity of the reco track
track_etaerr	std::vector<float>	error on pseudorapidity of the reco track
track_dxy	std::vector<float>	transverse impact parameter of the reco track
track_dxyerr	std::vector<float>	error on the transverse impact parameter of the reco track
track_dsz	std::vector<float>	longitudinal impact parameter of the reco track
track_dszerr	std::vector<float>	error on the longitudinal impact parameter of the reco track
track_qoverp	std::vector<float>	charge over momentum of the reco track
track_qoverperr	std::vector<float>	error on charge over momentum of the track
track_vx	std::vector<float>	x position of the vertex of the reco track
track_vy	std::vector<float>	y position of the vertex of the reco track
track_vz	std::vector<float>	z position of the vertex of the reco track
track_algo	std::vector<Int_t>	algorithm type of the reco track
track_hit_global_x	std::vector<std::vector<float> >	global x position of the RecHit associated to the reco track
track_hit_global_y	std::vector<std::vector<float> >	global y position of the RecHit associated to the reco track
track_hit_global_z	std::vector<std::vector<float> >	global z position of the RecHit associated to the reco track
track_hit_local_x	std::vector<std::vector<float> >	local x position of the RecHit associated to the reco track
track_hit_local_y	std::vector<std::vector<float> >	local y position of the RecHit associated to the reco track
track_hit_local_x_error	std::vector<std::vector<float> >	error on local x position of the RecHit associated to the reco track
track_hit_local_y_error	std::vector<std::vector<float> >	error on local y position of the RecHit associated to the reco track
track_hit_sub_det	std::vector<std::vector<unsigned int> >	subdetector generating the hit [1 PixelBarrel, 2 PixelEndcap, 3 TIB, 4 TID, 5 TOB, 6 TEC] associated to the reco track
track_hit_layer	std::vector<std::vector<unsigned int> >	layer/disk of the subdetector generating the hit associated to the reco track

How were these data selected?

This dataset was produced with the software available in:

TrackerRecHitProducerTool - Example workflow to add tracker hits to CMS Run1 AOD and to produce full event ROOT ntuple with tracker hits

How can you use these data?

The use of these files does not require any software specific to the CMS experiment. An example notebook is provided. The code reads the ntuples and produces a scatter plot of the rechits from three events.