| Parameter | Definition | How it was calculated | 
| 
 ExRootLHEFEvent
 | 
  | Number | event number |  | 
  | Nparticles | number of particles in the event | hepup.NUP | 
  | ProcessID | subprocess code for the event | hepup.IDPRUP | 
  | Weight | weight for the event | hepup.XWGTUP | 
  | ScalePDF | scale in GeV used in the calculation of the PDFs in the event | hepup.SCALUP | 
  | CouplingQED | value of the QED coupling used in the event | hepup.AQEDUP | 
  | CouplingQCD | value of the QCD coupling used in the event | hepup.AQCDUP | 
| 
 ExRootLHEFParticle
 | 
  | PID | particle HEP ID number | hepup.IDUP[number] | 
  | Status | particle status code | hepup.ISTUP[number] | 
  | Mother1 | index for the particle first mother | hepup.MOTHUP[number][0] | 
  | Mother2 | index for the particle last mother | hepup.MOTHUP[number][1] | 
  | ColorLine1 | index for the particle color-line | hepup.ICOLUP[number][0] | 
  | ColorLine2 | index for the particle anti-color-line | hepup.ICOLUP[number][1] | 
  | Px | particle momentum vector (x component) | hepup.PUP[number][0] | 
  | Py | particle momentum vector (y component) | hepup.PUP[number][1] | 
  | Pz | particle momentum vector (z component) | hepup.PUP[number][2] | 
  | E | particle energy | hepup.PUP[number][3] | 
  | M | particle mass | hepup.PUP[number][4] | 
  | PT | particle transverse momentum |  | 
  | Eta | particle pseudorapidity |  | 
  | Phi | particle azimuthal angle |  | 
  | Rapidity | particle rapidity |  | 
  | LifeTime | particle invariant lifetime
 (c*tau, distance from production to decay in mm) | hepup.VTIMUP[number] | 
  | Spin | cosine of the angle between the particle spin vector
 and the decaying particle 3-momentum,
 specified in the lab frame. | hepup.SPINUP[number] | 
| 
 ExRootGenEvent
 | 
  | Number | event number | hepevt.nevhep | 
| 
 ExRootGenParticle
 | 
  | PID | particle HEP ID number | hepevt.idhep[number] | 
  | Status | particle status | hepevt.isthep[number] | 
  | M1 | particle 1st mother | hepevt.jmohep[number][0] - 1 | 
  | M2 | particle 2nd mother | hepevt.jmohep[number][1] - 1 | 
  | D1 | particle 1st daughter | hepevt.jdahep[number][0] - 1 | 
  | D2 | particle 2nd daughter | hepevt.jdahep[number][1] - 1 | 
  | E | particle energy | hepevt.phep[number][3] | 
  | Px | particle momentum vector (x component) | hepevt.phep[number][0] | 
  | Py | particle momentum vector (y component) | hepevt.phep[number][1] | 
  | Pz | particle momentum vector (z component) | hepevt.phep[number][2] | 
  | PT | particle transverse momentum |  | 
  | Eta | particle pseudorapidity |  | 
  | Phi | particle azimuthal angle |  | 
  | Rapidity | particle rapidity |  | 
  | T | particle vertex position (t component) | hepevt.vhep[number][3] | 
  | X | particle vertex position (x component) | hepevt.vhep[number][0] | 
  | Y | particle vertex position (y component) | hepevt.vhep[number][1] | 
  | Z | particle vertex position (z component) | hepevt.vhep[number][2] | 
| 
 ExRootGenJet
 | 
  | E | jet energy |  | 
  | Px | jet momentum vector (x component) |  | 
  | Py | jet momentum vector (y component) |  | 
  | Pz | jet momentum vector (z component) |  | 
  | PT | jet transverse momentum |  | 
  | Eta | jet pseudorapidity |  | 
  | Phi | jet azimuthal angle |  | 
  | Rapidity | jet rapidity |  | 
  | Mass | jet invariant mass |  | 
| 
 ExRootEvent
 | 
  | Number | event number |  | 
  | Trigger | trigger word |  | 
| 
 ExRootMissingET
 | 
  | MET | mising transverse energy |  | 
  | Phi | mising energy azimuthal angle |  | 
| 
 ExRootPhoton
 | 
  | PT | photon transverse momentum |  | 
  | Eta | photon pseudorapidity |  | 
  | Phi | photon azimuthal angle |  | 
  | EhadOverEem | ratio of the hadronic versus electromagnetic energy
 deposited in the calorimeter |  | 
| 
 ExRootElectron
 | 
  | PT | electron transverse momentum |  | 
  | Eta | electron pseudorapidity |  | 
  | Phi | electron azimuthal angle |  | 
  | Charge | electron charge |  | 
  | Ntrk | number of tracks associated with the electron |  | 
  | EhadOverEem | ratio of the hadronic versus electromagnetic energy
 deposited in the calorimeter |  | 
| 
 ExRootMuon
 | 
  | PT | muon transverse momentum |  | 
  | Eta | muon pseudorapidity |  | 
  | Phi | muon azimuthal angle |  | 
  | Charge | muon charge |  | 
  | Ntrk | number of tracks associated with the muon |  | 
  | PTiso | sum of tracks transverse momentum within a cone of radius R=0.4
 centered on the muon (excluding the muon itself) |  | 
  | ETiso | ratio of ET in a 3x3 calorimeter cells array around the muon
 (including the muon's cell) to the muon PT |  | 
  | JetIndex | index of the closest jet |  | 
| 
 ExRootTau
 | 
  | PT | tau transverse momentum |  | 
  | Eta | tau pseudorapidity |  | 
  | Phi | tau azimuthal angle |  | 
  | Charge | tau charge |  | 
  | Ntrk | number of charged tracks associated with the tau |  | 
  | EhadOverEem | ratio of the hadronic versus electromagnetic energy
 deposited in the calorimeter |  | 
| 
 ExRootJet
 | 
  | PT | jet transverse momentum |  | 
  | Eta | jet pseudorapidity |  | 
  | Phi | jet azimuthal angle |  | 
  | Mass | jet invariant mass |  | 
  | Ntrk | number of tracks associated with the jet |  | 
  | BTag | 1 or 2 for a jet that has been tagged as containing a heavy quark |  | 
  | EhadOverEem | ratio of the hadronic versus electromagnetic energy
 deposited in the calorimeter |  | 
  | Index | jet index in the LHC Olympics file |  |