1 / 14

Z   update and FDR2

Stay updated on Z→ττ lepton-hadron analysis with insights from a recent data exercise, using sophisticated techniques to fine-tune EtMiss and Tau-jet scales. Processed using trigger-aware methods without relying on Monte Carlo data. Results and strategies are discussed.

Télécharger la présentation

Z   update and FDR2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Z update and FDR2 D. Cavalli, W. Davey, C. Pizio, S.Resconi

  2. Z    lepton-hadron analysis • MS channel with leptons, t, ETMiss • s(Z   ) =1641pb • in 100pb-1 expect: ~ 70000 Z   lepton-hadron • (~ 7000 with pTe or pTmu> 15GeV) • - Select Z  lep-had, severe cuts applied to have low background level • - Signal events have opposite sign lepton and t-jet (OS events) • Background events (QCD,Wmn,Wen,tt,Zee,Zmm,WW) have similar • probability to be OS or SS. Estimate backgd from SS events and subtract • Use the reconstructed invariant mass to tune the EtMiss scale in situ • Use from the reconstructed visible mass to tune the Tau-jet scale • Use Full simulated events (12.0.6) for Signal and backgds (also Atlfast QCD!) • Trigger aware Analysis: Single lepton Trigger events (EF6mu, EFe10i) • Analisys performed as in real life: not using MC information

  3. Z   in first data Very short update: • CSC Analysis (data from rel. 12) redone not using b-tagging • Restart with data from rel.14 • from AOD/TauDPD (using ARAna tool ) • check Tau-merged container (TauRec/Tau1p3p) • Check subtraction of background using SS events • In W+jets events OS > SS  use data to find the OS/SS ratio and correct • very first results from FDR2 data

  4. Z   Invariant mass results (no b-tagging) Invariant mass Signal + Backgds In 100 pb -1 in the mass bin (66-116 GeV) 237 signal evts (209 with b-tagging) 32 backgds evts OS (B ≈ 13% S) (16) 28 backgds evts SS (26) S/√B=42 Ztt: OS 237+/-8, SS 11+/-2 Jets: OS 20+/-11, SS 13+/-9 Wmn: OS 6+/-1, SS 2+/-1 Wen: OS 2+/-1, SS 1+/-1 tt: OS 3+/-2, SS 0 Zee: OS 1+/1, SS 1+/1 Zmm: OS 0, SS 0 Opposite Sign – Same Sign • In the first data the b-tagging could be not robust enough - invariant mass analysis still under control - visible mass more critical (B increases from 20 to 36%)

  5. Z   fromFDR2 data Our strategy for FDR2 exercise: • Run TauDPDMaker with Ganga on FDR2 AOD (POOL) data distributed on the 4 T2 IT sites: • to get DPD1 (POOL) and DPD3 (ROOT) data at MI T2 • Run ARana on same AOD and DPD1 events in MI T2: • to check results between the 2 different formats • Run ARana on increased statistics of DPD1 events in MI T2: • to get final results/plots • Run on Egamma and Muon streams

  6. FDR2 exercise: technical issuesused Atlas release 14.1.0 What did NOT work  • Some time spent to succeed in compiling ARana (on MI UI) : • needed 20+ tags to compile ARana (~ 4h compilation time !!) • RFIO problem to read data from SE with ROOT 5.18.00 : • Savannah bug posted by F. Prelz (https://savannah.cern.ch/bugs/?37691) • TauDPDMaker problem in producing DPD3(ROOT) from DPD1(POOL) : • problem reported to hn-atlas-tauwg, D. Cote is investigating • it works commenting tau What worked  • Run TauDPDMaker with Ganga (on lxplus), now it works also on MI UI: • Initial Ganga script thanks to Leonardo • sent jobs to the 4 IT T2 sites: • running on Egamma/Muon AOD streams • storing the output DPD1 to Milan SE • This is one of the first attempt to run TauDPDMaker on the Grid !! • Run ARana (on MI UI) on input FDR2 AOD and DPD1: • Modified version by Will to switch between different data formats (AOD, DPD1(3), CBNT) • It worked just commenting MCTruth

  7. ESD/AOD (pool.root) Primary DPDs (pool.root) Primary DPDs (pool.root) Secondary DPDs (pool.root) Tertiary DPDs (root ntuple) FDR2 exercise: DPD from TauDPDMaker • Official DPDs for Tau and EtMiss performance & trigger groups: • DPD_TAUWZ, DPD_TAUDIJETS • DPD is skimmed (excluding entire events), slimmed (excluding some objects), thinned (excluding part of objects) AOD Selection for DPD_TAUWZ Zll, Wl & Z/Wjj: • MET > 10 (30) GeV for Z (W) • SumET < 400 GeV • Z/Wlep: at least 2 (1) lepton(s) in the event for Z (W) • pT > 15 GeV,  < 2.5 • Z/Wjets: at least 2 Cone4H1TopoParticleJets • pT > 15 GeV,  < 2.5 Skim eff. and evt size for DPD_TAUWZ Zll, Wl & Z/Wjj: • skim eff % ~ 40 % • DPD file size ~ 1/8 -1/10 AOD file size • DPD proc. time ~ 1/3 AOD proc. Time

  8. FDR2 exercise: AOD vs DPD_TAUWZ Comparison between the AOD sample in MI: fdr08_run2.0052290(3).physics_Egamma(Muon).merge.AOD.*** and the DPD_TAUWZ sample produced with Ganga on the SAME events =AOD =DPD cuts applied: pT(e,μ) > 15 GeV, (e, μ) < 2.5 Id/isol

  9. FDR2 exercise: AOD vs DPD_TAUWZ AOD SumET EtMiss DPD

  10. FDR2 exercise: AOD vs DPD_TAUWZ Obtained same number of events (last plot) after having applied the same cuts on both AOD and DPD evt samples: - 1 id ele, 1 id. , (pT, h cuts, Id), SumET 400, MET  20, mT(lept,EtMiss)<50 =AOD =DPD Same distribution !

  11. FDR2 exercise: analysis on DPD_TAUWZ size: 24Gb CPU time: 3h/300kevts (1/2 of statist. at 1032) • Final analysis and plots on an increased statistics of DPD_TAUWZ: • fdr08_run2.0052290(3).physics_Egamma(Muon).merge.DPD_TAUWZ.*** • fdr08_run2.0052280(3).physics_Egamma(Muon).merge.DPD_TAUWZ.*** • To increase statistics used both ideal and misaligned data 4 runs correspond to an integrated L = 1.44 pb-1 (0.36 pb-1 each) • Z  x-section = 1669 pb, expected 2400 Z , 23 OS (5 SS) events after all cuts in mass bin. Invariant  mass OS and SS: All cuts Invariant  mass mT(lept,EtMiss)

  12. Secondary DPDs (pool.root) FDR2 exercise: Conclusions First realistic test of the analysis model and tools: Standard Reco ARana TauDPDMaker ESD/AOD (pool.root) Analisys Final plots (histo.root) and numbers Primary DPDs (pool.root) Tertiary DPDs (root ntuple)

  13. FDR2 exercise: Conclusions First realistic test of the analysis model and tools: • Send Ganga jobs to the 4 IT T2 to run TauDPDMaker on input AODs to produce output DPD1 • Store output DPD1 on MI SE • Send ARana jobs via Grid to the Mi T2 or run it locally to produce output plots/numbers 2 NA- T2 MI-T2 3 1 1 WN 2 RB WN 1 RO –T2 WN 3 3 3 1 CE RB=resource broker CE=computing element SE=storage element WN=worker node SE LNF- T2 2

  14. Z   in first data Next work plan: • Checks • Redo Analysis with rel 14 data • Z  cross section measurement • single lepton trigger efficiency from Z  ll • lepton Reco/Id/Isolation efffrom Z  ll • Nobs= OS evts, Nbkg=SS evts • Acc of Analysis • from invariant mass analysis • from visible mass analysis • determine  reconstruction/Identification efficiency in-situ Present Analysis for CSC Notes: Inv mass: s=1565+/- 107 Vis mass: s=1696+/- 94 Only MC stat errors…

More Related