Observables

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Identifying/analyzing observables, ratios of observables, systematic uncertainties (renorm.scale, PDFs), obtaining cross sections from public codes/ntuples. The observables might involve both jets and leptons. Identify for which process/observable NLO calculations are available. What is suitable for start-up (eg. normalization issues, Drell-Yan, top, ...)

People signed up for this group:

  • Bruce
  • Rohini
  • Kajari
  • Gudrun
  • Vitaliano
  • Tanju
  • Peter
  • Frank-Peter
  • Laura
  • Giacinto
  • Jon
  • Matthew
  • Matteo
  • Nikolas
  • Alessandro
  • Joanna
  • Lorenzo
  • Jeppe
  • Paolo
  • Radja
  • Reinhard


Contributions from several discussions so far

  • Normalization of tT cross section, using Z and/or Z*, or Z at high pT (in order to enhance gluon contribution and thus reduce anti-correlation

with the gg-PDF needed for the tT production)

  • cf. the discussion about Higgs systematics
    • Rohini, Bruce, Michael Dittmar, Guenther, Joey, Nikolas
  • Same as above, but normalization of Di-boson production
    • Bruce, Nikolas
  • Action item for these normalization studies: get numbers on exp. and theo. uncertainties for the Z (large pt) counting for a given int. lumi.

  • detailed study of di-lepton (DY) Production, all relevant systematics
    • Samir, Kajari

  • discussions on ratios of cross sections in W/Z+jet production
    • example : sigma(W+>=3jets)/sigma(W+>=2jets), look at 3rd jet production as function of rap diff. of leading 2 jets
    • Z+jet : analysis of hadronic part of event, such as event shapes
    • Jeppe,Vitaliano, Piergiulio, Alessandro,Joey

  • discussion of relevant observables in QCD incl. jet production
    • incl. cross section, ratio of di-jet production in diff. rap. bins
    • clear wish (high priority): obtain NLO+shower code for di-jet production
    • Paolo

  • discussion on observables involving photons
    • W+gamma (comparison of available calc.), gamma-gamma final states
    • important issue: definition of isolation
    • Kajari, Susan,Joey

  • establishment of Root Ntuples for easy use by experimentalists, containing all necessary info from LO/NLO codes output, see subpage ROOT ntuples
    • Joey, Joanna,Frank-Peter

  • comparison of NLO predictions (e.g. W + 3 jets) for different observables/scales in order to understand the uncertainties of scale choices/cross section results; using knowledge of existing NLO calculations to understand motivated scale choices at LO for uncalculated (to NLO) cross sections. Lit.: Scale setting and resummation of logarithms in pp -> V + jets
    • Joey, Nikolas, Giulia, Tanju...
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