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Slimmed Ntuple Format

The slimmed ntuples contain a simple ROOT tree containing the full information used by SimpleAnalysis. This is fairly easy to create as for example done in the script. The variables needed are listed and explained in the table below. The most complicated variable is "id" variable which is a 32-bit pattern used to defined which particle identification criteria an object passes. The definition varies by object type and for the detailed list, one needs to consult the AnalysisObject.h header file.

Group Variables Description
Electrons ("el_") pt, eta, phi, charge, id, motherID Momentum components, charge, id bit patttern, pdgId of parent particle
Muons ("mu_") pt, eta, phi, charge, id, motherID as above
Taus ("tau_") pt, eta, phi, charge, id, motherID as above
Photons ("ph_") pt, eta, phi, charge, id, motherID as above
B-hadrons ("bhadron_") pt, eta, phi, charge, id, motherID as above
Jets ("jet_") pt, eta, phi, m, id anti-kt r=0.4 jet four momenta, id bit pattern. Charge and parent pdgID is not used
Track jets "trackjet_") pt, eta, phi, m, id, motherID variable radius jet from charge particles only
Large-R jets ("fatjet_") pt, eta, phi, m, charge, id, motherID Trimmed, anti-kt r=1.0 jets. Charge is used for D2*1e5
Etmiss ("met_") pt, phi Missing transverse momentum and its angle
Hard-scatter truth ("HSTruth_") pt, eta, phi, charge, m, id, motherID Four momentum, charge and pdgId of SUSY particles, b/t quarks, W/Z/h bosons
prodVx, prodVy, prodVx, decayVx, decayVy, decayVz Production and decay vertex location
pdf id1, x1, pdf1, id1, x1, pdf1, scale pdgId of colliding partons, their momentum fraction, Q-scale and PDF value
other sumet, genHT, genMET Scalar sum of transverse momenta of all visible particles, jets, and invisible particles
Event, eventWeight, mcWeights Event number, default event weight and optionally alternative events weights from PDF variations
mcChannel, mcVetoCode, susyChannel Internal ATLAS numbering

Last update: February 24, 2022