Tau Efficiency Measurement using Tag and Probe with Ztautau events.

Introduction

Public Results:

• vis mass plots for 2011 conferences (Internal CDS entry)
• Tau trigger efficiency (Internal CDS entry)

Validation

• ZtautauTagAndProbeValidation

Goals

First Pass: (By mid June)

• Quick re-optimisation if necessary on 2011 data
• Extract single efficiency number with ntrack and |charge| in tau selection to supress QCD events
• Run on Period A-D (160pb-1 with no LAr problem)
• Evaluate Systematics
• Finalise first Tau Eff measurement with channel

Second Pass: (late summer)

• Include Electron Leg
• Include all available data (including LAr problem)
• Extract 1P and 3P/MP efficiency
• Release ntrack and |charge| requirement from BaseTau selection for inclusive measurement.
• Include Lepton Isolation fit for QCD estimation

Other:

• Tau Trigger measurement:
  • Use Analysis including Tau ID to get pure true tau sample
  • Read 2010 note here
• Tau Scale measurement:
  • Also use tight tau id to get very pure tau sample, then fit vis mass dist.

Useful Links

• ZToTwoTausToLepHad
• ZToTwoTausToLepHad7TeVAnalysisCrossSectionMeasurement
• ZToTwoTausToLepHad7TeVValidation
• ZToTwoTausToLepHad7TeVAnalysis2011
• HiggsRecommendationsForWinterConf2011

Tau Links:

• TauWG
• TauWG D3PD list
• TauWD D3PD Maker
• TauMC7TeV Info

ATLAS Links:

• Lumi Calculator
• GRL twiki
• Run Query
• Trigger Query
• Panda DaTRI request - request to AUSTRALIA-ATLAS_SCRATCHDISK
• PAT User Analysis Tools
• Statistics Tools

Analysis Code

• Run on tauPerf D3PDs
• Process with ZToTwoTausAnalysis (modified for Tau Eff measurement) - NOTE: Should we chuck our modified code in a repository somewhere?
• Dump out summary TTrees with derived quantities for data and MC samples
• Process TTrees with TauEffPyTools - the package we developed for the analysis.

Links to Code:

• ZToTwoTaus BenchMarkCode wiki
• ZToTwoTausAnalysis SVN
• TauEffPyTools SVN

2011 Data Info

• Lumi info (178044 - 180212): https://atlas-datasummary.cern.ch/lumicalc/results/61d856/result.html
• Runs A-D have no LAr problem.

• GRLS (NEW):
  • Extracted GRLs for specific periods from Official GRL 'data11_7TeV.periodAllYear_DetStatus-v16-pro08-03_Z_tautau_lh.xml', using 'dqu_grl_per_period.py'.
    • Output GRLs:
      • [[][PeriodA]]
      • [[][PeriodB]]
      • [[][PeriodD]]
      • [[][PeriodE]]
  • Ran Lumi Calc on GRLs:
    • Settings:
      • OflLumi-7TeV-001
      • L1_EM14
      • EF_mu18
    • Results:
      • Period A, no events, L = 0 pb-1
      • Period B, [[][result]], [[][histos]], L = pb-1
      • Period D, [[][result]], [[]], L = 147.963 pb-1
      • Period E, [[][result]], [[][histos]], L = 41.6104 pb-1
      • Period F, [[][result]], [[][histos]], L = 124.49 pb-1

• GRLS (OLD):
  • Ran 'ATLAS Good Run List Generator' for periods, A, B, D, E:
    • Settings:
      • StandardModel.Z_tautau_lh
      • data11_7TeV period X
      • DetStatus-v13-pro08-02
    • Output GRLs:
      • PeriodA
      • PeriodB
      • PeriodD
      • PeriodE
  • Ran Lumi Calc on GRLs:
    • Settings:
      • OflLumi-7TeV-001
      • L1_EM14
      • EF_mu18
    • Results:
      • Period A, no events, L = 0 pb-1
      • Period B, result, histos, L = 11.268 pb-1
      • Period D, result, histos, L = 147.963 pb-1
      • Period E, result, histos, L = 41.911 pb-1
      • Period A-D, histo, L = 159.231
    • MC Pileup Histos:
      • mc10a
      • mc10b

2011 Recommendations

• Summary of Higgs PLHC Recommendations
• Muons - PLHC2011 Muon Recommendations

2011 Code

• PileupReweighting
• ZToTwoTausAnalysis2011

TO DOs

High Priority

• Check for information on Pileup Reweighting.
  • Upcoming Jet meetings on pileup:
    • Wednesday 8 at 3pm, in room 40-R-D10, "event-by-event pile-up corrections for jets" - https://indico.cern.ch/conferenceDisplay.py?confId=142025
    • Friday 10 at 9am, "Jet Theory discussion (Gavin Salam)" - https://indico.cern.ch/conferenceDisplay.py?confId=142026
    • Tuesday 7, "JVF" - https://indico.cern.ch/conferenceDisplay.py?confId=141915

• Check kW with OS/SS events

• Do Isolation Optimisation using new Iso Criteria:
  • EtCone20/pt
  • NuCone40 or PtCone40/pt ?

• Check Vertex Counting!
• Check pileup reweighting

• Muon isolation measurement using Zmumu Tag & Probe (David):
  • Read Appendix B in Ztautau cross-section support note
  • Redo analysis using our selection for probe.
  • If we are going to do isolation fitting, we might need to look at actually re-weighting MC iso dist, rather than just applying efficiency corrections. But that is second iteration.

• Improving QCD estimates:
  • Fitting Isolation distributions:
    • Use e-mu QCD control region to get muon isolation shape for QCD events.

• • Using 2D fit with 2 good QCD discriminators to extract QCD contribution
  • Check Ros/ss correlations vs Isolation
  • Fix TauEffCycle:
    • remove ntrack and charge from BaseTau selection
    • put in as preference rather than flat cut
    • Put in possibility to use mu-mu control region for QCD LepIso measurement.
• plotQuick -> replace all instances of weight = '1.' to weight = cacheGet( 'tree_weight' )
  • then in the actual hist getter put if weight == None: weight = '1.'

Med Priority

• Calculate/Implement experimental systematic uncertainties
• Make 1fb-1 estimates:
  • Mass Fitting (Will)

Low Priority

• Include Electron Channel
• Look at Shao Mass
• Invariant Mass Optimisation:
  • Cut on recoil jet to remove shoulder in signal mass distribution
• Get simple counting Number Estimates for InvMass Analysis (David)

• Optimisation:
  • Write full optimiser tool that:
    • Takes in a list of variables
    • Optimises cuts on vars by Minimising ∆N(sig)/N(sig), where:
      • N(sig) = N(data) - Nest(bkg)
      • ∆N(sig)^2 = ∆N(data)^2 + ∆Nest(bkg)^2 = N(data) + (Nest(bkg)*(∆N/N)sys)^2
    • Orders cuts by effectiveness

Completed Tasks (Move here once done)

• Fitting (Will)
  • Finish ToyMC implementation
  • Add FittingTools module to TauEffPyTools
  • Fit individual backgrounds and set normalisation ranges in fit (eg. +- 10-20%)
  • Implement Toy MC to evaluate systematic uncertainty from MC sample normalisation
  • Ask EB how to implement direct systematic calculation in fit

• Get simple counting Number Estimates for VisMass Analysis (David)
• Make 1fb-1 estimates:
  • Event Counting (David)

• Optimise Analysis Selection (David)
  • Currently 1/7 signal purity in VisMass, should aim for ~ 1/5
  • Variables to Look at:
    • Lepton Isolation
    • Lepton Pt
    • dPhi( lep, tau )
    • MET significance

• Start Running on 2011 D3PDs
  • Get 2011 ZToTwoTaus branch running (David)
    • Make simple comparison to 2010
    • Fix any major problems with code (see below)
  • Data:
    • Run over periods A-D (period E has LAr FEB problem)
    • Calculate total Lumi (use Lumi calc tool)
  • run over mc10a skims here: /home/data/ZtautauLHAnalysis/mc10a

• Changes to be implemented:
  • General Config:
    • Set Data Lumi to that calculated above for period A-D. (i think this is in samples.py)
  • Pileup Reweighting:
    • only on MC
    • remove vertex reweighting
    • copy over MC and data lumi block hists (from above), put all period A,B,D,E and A-D in.
    • Allow input hists to be configurable in code, and set to run on period A-D.
  • Muons:
    • Problem in TRT cleaning:
      • TRT has an int->float conversion error: nOut/n < 0.9, but nOut/n = 0 since both ints
      • MuonSelectorTool.cxx lines: 194 & 197, should be (float)nOut/(float)n<0.9
    • Efficiency corrections:
      • should be using StacoTightEffScaleFactors not StacoCBScaleEffFactors.
      • See PLHC2011 Muon Recommendations for implementation.
    • Isolation corrections:
      • There are no recommended iso corrections for muons yet. Apparently the iso dist matches well after pileup reweighting. We should check this.

-- WillDavey - 20-Apr-2011