Variables
Some variables have changed names, some have been removed and some are added. This page provides all the information needed to convert your code from the previous release to the new one. You can see the complete list of variables in the ATLAS Open Data 2025 beta release here
Minor changes
The table below summarizes the variables which have changed name in the new release, but where the usage of the variable is more or less the same.
| In previous release | In new release | Comment |
|---|---|---|
scaleFactor_<...> | ScaleFactor_<...> | Starting with capital S |
scaleFactor_BTAG | ScaleFactor_FTAG | New and improved way to calculate scalefactor for b-tagging algorithm using continuous working point |
largeRjet_<...> | largeRJet_<...> | Capital J in jet |
largeRjet_eta | largeRJet_Eta | Capital E in eta was used by mistake in 2025 beta release. Will be fixed in next release. |
met_et | met | Same content, but new name |
tau_BDTid | Replaced by tau_RNNJetScore and tau_RNNEleScore | Deep neural network scores used to identify hadronically and leptonically decaying taus, respectively |
tau_isTightID | tau_isTight | Same content, but new name |
jet/lep/photon/tau_E | jet/lep/photon/tau_e | Energy of object, now using small e for energy |
photon_ptcone30 | photon_ptcone20 | Similar content |
photon_etcone20 | photon_topoetcone40 | Similar content |
jet/lep/photon/tau_trigMatched | jet/lep/photon/tau_isTrigMatched | Same content, but adding an is |
lep_trackd0pvunbiased | lep_d0 | Similar content, but new name |
lep_tracksigd0pvunbiased | lep_d0sig | Similar content, but new name |
lep_ptcone30 | lep_ptvarcone30 | Similar content, but new name |
lep_etcone20 | lep_topoetcone20 | Similar content, but new name |
jet_MV2c10 | jet_btag_quantile | New b-tagger implemented, now using the continuous working point (see further down for more information) |
XSection | xsec | Same content, but new name |
SumWeights | sum_of_weights | Same content, but new name |
New variables
The variables in the table below are all new variables, which are not available in the previous release.
| New Variables | C++ type | Description |
|---|---|---|
num_events | double | number of originally number of simulated events, neglecting the event weights |
sum_of_weights | double | the square root of the sum of the event weights |
sum_of_weights_squared | double | the square root of the sum of the square of the event weights |
kfac | float | corrections to the cross section due to higher order calculations |
met_mpx | float | x-component of the missing momentum vector |
met_mpy | float | y-component of the missing momentum vector |
ScaleFactor_TauTRIGGER | float | scalefactor for different operating efficiencies of used tau triggers |
ScaleFactor_DiTauTRIGGER | float | scalefactor for different operating efficiencies of used ditau triggers |
photon_isLooseID | vector<bool> | boolean indicating whether photon satisfies loose ID reconstruction criteria |
photon_isLooseIso | vector<bool> | boolean indicating whether photon satisfies loose isolation criteria |
photon_isTightIso | vector<bool> | boolean indicating whether photon satisfies tight isolation criteria |
lep_isLooseID | vector<bool> | boolean indicating whether lepton satisfies loose ID reconstruction criteria |
lep_isMediumID | vector<bool> | boolean indicating whether lepton satisfies medium ID reconstruction criteria |
lep_isLooseIso | vector<bool> | boolean indicating whether lepton satisfies loose isolation criteria |
lep_isTightIso | vector<bool> | boolean indicating whether lepton satisfies tight isolation criteria |
ScaleFactor_ElTRIGGER | Float_t | scalefactor for different operating efficiencies of used single electron triggers |
ScaleFactor_MuTRIGGER | Float_t | scalefactor for different operating efficiencies of used single muon triggers |
ScaleFactor_MLTRIGGER | Float_t | scalefactor for different operating efficiencies of used multilepton triggers |
TriggerMatch_DILEPTON | Float_t | scalefactor for different operating efficiencies of used di-lepton triggers |
jet_pt_jer1 | vector<float> | transverse momentum of the jet after applying a specific systematic uncertainty from the jet energy resolution calibration |
jet_pt_jer2 | vector<float> | transverse momentum of the jet after applying a specific systematic uncertainty from the jet energy resolution calibration |
ScaleFactor_JVT | Float_t | scalefactor for jet vertex tagger (JVT) algorithm using the neural net (NN) working point |
trigDE | bool | boolean whether the event has been selected by any of the di-electron triggers |
trigDM | bool | boolean whether the event has been selected by any of the di-muon triggers |
trigMET | bool | boolean whether the event has been selected by any of the missing transverse energy triggers |
trigT | bool | boolean whether the event has been selected by any of the single tau triggers |
trigDT | bool | boolean whether the event has been selected by any of the di-tau triggers |
truth_elec_eta | vector<float> | pseudo-rapidity of the truth electrons |
truth_elec_n | Int_t | number of truth electrons |
truth_elec_phi | vector<float> | azimuthal angle of the truth electrons |
truth_elec_pt | vector<float> | transverse momentum of the truth electrons |
truth_jet_eta | vector<float> | pseudo-rapidity of the truth jets |
truth_jet_m | vector<float> | mass of the truth jets |
truth_jet_n | Int_t | number of truth jets |
truth_jet_phi | vector<float> | azimuthal angle of the truth jets |
truth_jet_pt | vector<float> | transverse momentum of the truth jets |
truth_met | Float_t | truth missing transverse energy |
truth_met_phi | Float_t | azimuthal angle of the truth missing transverse energy |
truth_muon_eta | vector<float> | pseudo-rapidity of the truth muon |
truth_muon_n | Int_t | number of truth muons |
truth_muon_phi | vector<float> | azimuthal angle of the truth muons |
truth_muon_pt | vector<float> | transverse momentum of the truth muons |
truth_photon_eta | vector<float> | pseudo-rapidity of the truth photons |
truth_photon_n | Int_t | number of truth photons |
truth_photon_phi | vector<float> | azimuthal angle of the truth photons |
truth_photon_pt | vector<float> | transverse momentum of the truth photons |
truth_tau_eta | vector<float> | pseudo-rapidity of the truth taus |
truth_tau_n | Int_t | number of truth taus |
truth_tau_phi | vector<float> | azimuthal angle of the truth taus |
truth_tau_pt | vector<float> | transverse momentum of the truth taus |
Changes to the b-tagging
The new release contains a better and improved b-tagger, named DL1dv01 (see publication). In the previous release one had to use fixed working points of b-tagging efficiency. The table below shows which cut needs to be applied to in order to reflect a given working point (WP). I.e. if you used the 85% WP in the previous release you need to require jet_btag_quantile>=2 in the new release.
| WP in previous release | Cut in new release |
|---|---|
| 100% | jet_btag_quantile>=1 |
| 85% | jet_btag_quantile>=2 |
| 77% | jet_btag_quantile>=3 |
| 70% | jet_btag_quantile>=4 |
| 60% | jet_btag_quantile>=5 |
Scaling to cross section and luminosity
In the 2025 beta release all the information needed to do the scaling of the MC to the integrated luminosity of the data set (36 inverse femtobarn) are available in the ntuples.
This scale factor then needs to be multiplied with all the scale factors relevant for the analysis you are doing (e.g. if you are using b-jets in your selection you need to multiply with ScaleFactor_FTAG, if you use electrons; scaleFactor_ELE &c).