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Variable names

Here are the definitions of the variable names as used in the analysis code and in the ntuples.

variable namentuple branchnametypedescription
runNumberrunNumberintrun identifier
eventNumbereventNumberintevent identifier
channelNumberintData sample ID eg WW sample 105985
mcWeightmcWeightfloatweight of a simulated event
pvxp_npvxp_nintnumber of primary vertices
vxp_zvxp_zfloatz-position of the primary vertex
SF_PILEUPscaleFactor_PILEUPfloatscalefactor for pileup reweighting. It effectively reweights the profile of average interactions per bunch crossing so that simulated data is the same as measured data.
SF_ElescaleFactor_ELEfloatscalefactor for electron efficiency
SF_MuscaleFactor_MUONfloatscalefactor for muon efficiency
SF_BTagscaleFactor_BTAGfloatscalefactor for btagging algorithm. Should only be applied if analysis is specifically using b-tagging.
SF_TriggerscaleFactor_TRIGGERfloatscalefactor to account for the different operating efficiencies of the used triggers.
SF_JVFscaleFactor_JVFSFfloatscalefactor for jet vertex fraction.
SF_ZVertexscaleFactor_ZVERTEXfloatscalefactor to reweight the distribution of the z position of the primary vertex.
trigEtrigEboolboolean whether a standard trigger has fired in the egamma stream
trigMtrigMboolboolean whether a standard trigger has fired in the muon stream
passGRLpassGRLboolsignifies whether event passes the Good Run List may be put in isGoodEvent
hasGoodVertexhasGoodVertexboolsignifies whether the event has at least one good vertex where Ntracks > 4
Lep_nlep_nintnumber of preselected leptons
lep_truthMatchedvector<.bool>boolean indicating whether the lepton is matched to a simulated lepton
Lep_trigMatchlep_trigMatchedvector<.bool>boolean signifying whether the lepton is the one triggering the event
Lep_ptlep_ptvector<.float>transverse momentum of the lepton
Lep_etalep_etavector<.float>pseudorapidity of the lepton
Lep_philep_phivector<.float>azimuthal angle of the lepton
Lep_elep_Evector<.float>energy of the lepton
Lep_z0lep_z0vector<.float>z-coordinate of the track associated to the lepton wrt. the primary vertex
Lep_chargelep_chargevector<.float>charge of the lepton
Lep_pdgidlep_typevector<.int>number signifying the lepton type (e, mu, tau) of the lepton
Lep_flaglep_flagvector<.int>bitmask implementing object cuts
Lep_ptcone30lep_ptcone30vector<.float>scalar sum of track pTs in a cone of R=0.3 around lepton, not including lepton (p_T) itself
Lep_etcone20lep_etcone20vector<.float>scalar sum of track ETs in a cone of R=0.2 around lepton, not including lepton ET itself
Lep_d0lep_trackd0pvunbiasedvector<.float>d0 of the track associated to the lepton at the point of closest approach (p.o.a.)
Lep_d0siglep_tracksigd0pvunbiasedvector<.float>d0 signifcance of the track associated to the lepton at the p.o.a.
Met_etmet_etfloatTransverse energy of the missing momentum vector
Met_phimet_phifloatAzimuthal angle of the missing momentum vector
Jet_njet_nintnumber of selected jets
alljet_ninttotal number of jets in event
Jet_ptjet_ptvector<.float>transverse momentum of the jet
Jet_etajet_etavector<.float>pseudorapidity of the jet
Jet_phijet_phivector<.float>azimuthal angle of the jet
Jet_ejet_Evector<.float>energy of the jet
Jet_massjet_mvector<.float>invariant mass of the jet
Jet_jvfjet_jvfvector<.float>jet vertex fraction of the jet
Jet_flagjet_flagvector<.int>bitmask implementing object cuts of the top group
truepdgidjet_trueflavvector<.int>flavor of the simulated jet
isTrueJetjet_truthMatchedvector<.int>information whether the jet matches a simulated jet
jet_SV0vector<.float>Weight from algorithm that reconstructs Secondary Vertices associated with a jet
Jet_mv1jet_MV1vector<.float>Weight from algorithm based on Multi-Variate technique

The scalefactors correct for known differences between data and simulated data.

Reading the datasets.

The data is stored in ROOT tuples, which can be looked at directly using ROOT TBrowser.

In the provided analysis code the tuples are read by

Some of the variable names have been 'redefined' in
For example

self.Lep_d0 = self.activate("f", "lep_trackd0pvunbiased", max_Lep)

So the snappily named tuple variable lep_trackd0pvunbiased can be accessed as just Lep_d0 in the analysis code.

The Lorentz vector.

Four-momentum is a four-vector in spacetime. It is useful in relativistic calculations because it is a Lorentz vector. This means that it is easy to keep track of how it transforms under Lorentz transformations.

TLorentzVector is a general four-vector class in ROOT, which can be used either for the description of position and time (x,y,z,t) or momentum and energy (px,py,pz,E).

In it is defined

In various analyses it is used e.g.