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CMS Status Report

CMS Status Report. Darin Acosta University of Florida. Welcome to the inverse femtobarn era!. Recorded 3.1fb -1 of 3.4 fb -1 delivered Data-taking efficiency is about 90% Certification for physics analyses (up to August Stop) 84% for all systems perfect

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CMS Status Report

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  1. CMS Status Report Darin Acosta University of Florida

  2. Welcome to the inverse femtobarn era! • Recorded 3.1fb-1 of 3.4 fb-1 delivered • Data-taking efficiency is about 90% • Certification for physics analyses (up to August Stop) • 84% for all systems perfect • 91% for muon analyses (without calorimeters) • Used in 2011 physics analyses reported here: 0.23 – 1.7 fb-1 • most at 1.1 fb-1 • Luminosity uncertainty is 4.5% LHCC CMS Status Report -- D. Acosta

  3. Pile-Up Pile Up • The number of reconstructed vertices after the August Technical Stop increased by factor 1.5 (β*=1.5m 1m ) • Fills start with ~15 pile-up interactions • Vertex reconstruction still quite linear with luminosity • Total inelastic cross section also has been measured from pile-up • σinel(pp)= 68.0 ± 2.0 (Syst) ± 2.4 (Lum) ± 4 (Extrap.) mb. 20 vertices before after (PAS FWD-11-001) Averaged over fills. Nrec~ 0.7 x Npu LHCC CMS Status Report -- D. Acosta

  4. Operational Status 2010 2011 • Live detector channels • Very stable over 2010-11 • Forward pixels recovered some channelsPreshower has slight drop due to leakage current in one sensor type • Computing • Data rates and storage have been as expected (LHC live time and trigger rate) 95%  LHCC CMS Status Report -- D. Acosta

  5. CMS High Level Trigger Performance TAU + MUON • The CMS HLT is performing well in the high luminosity environment • Trigger algorithms and menus have increased in complexity • Over 200 multi-object triggers including tau and b-jet triggers, in addition to single object triggers for electrons, photons, muons, jets, total energy, & missing transverse energy (400 total paths) • Successfully using algorithms such as Particle Flow tau reconstruction Isolated Muon PT > 12 GeV & Hadronic Tau ET > 20 GeV trigger LHCC CMS Status Report -- D. Acosta

  6. Physics Analyses on 2010 Data 69 published, 7 in CWR, 18+ in preparation https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults Papers, and Physics Analysis Summaries (PAS): http://cdsweb.cern.ch/collection/CMS LHCC CMS Status Report -- D. Acosta

  7. Physics Analyses on 2010 Data • CMS reached 100 publications on August 3rd • 75 from LHC collision data, • 24 from the cosmic-ray runs of late 2009 • 1 is the CMS detector paper. 69 published, 7 in CWR, 18+ in preparation https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults Papers, and Physics Analysis Summaries (PAS): http://cdsweb.cern.ch/collection/CMS LHCC CMS Status Report -- D. Acosta

  8. Physics Analyses on 2011 Data Summer conference results all new since last LHCC meeting ! Cannot cover it all here 5 submitted, 45 PAS https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults Papers, and Physics Analysis Summaries (PAS): http://cdsweb.cern.ch/collection/CMS PAS PHY-11-000 LHCC CMS Status Report -- D. Acosta

  9. Standard Model

  10. Electroweak: access to proton PDFs PAS EWK-11-005, 013 • Wμν charge asymmetry vs. ημ W+charm • access to strange R±c = σ(W+c)/σ(W-c)=0.92 ±0.19(stat.)±0.04(syst.) Rc = σ(Wc)/σ(W+jets)=0.143 ±0.015(stat.)± 0.024(syst.) NLO predictions: R±c = 0.91±0.04 Rc =0.13±0.02 Secondary vertex decay length discriminator LHCC CMS Status Report -- D. Acosta

  11. Top: tt Cross Section, 1.1 fb-1 σ(NLO)=158±24 pb PAS TOP-11-003, 5, 6, 7 • Lepton+jets+b-tag • CMS most precise to-date ! • Dilepton channel (ee,eμ,μμ) • Require at least 1 b-tag • Dilepton channel (μ-τ) • Reconstruct hadronic tau decay • All-hadronic channel • kinematic fit for mtop • QCD shape from anti-b-tag data 2011 LHCC CMS Status Report -- D. Acosta

  12. Top Charge, Mass Asymmetries, 1.1fb-1 PAS TOP-11-014, 019 • Top charge asymmetry • Larger than expected @ Tevatron • Lepton+Jets channel • Δ(|η|) = |ηt| - |ηtbar| • AC = [N(Δ>0) - N(Δ<0)]/Ntot = -1.6 ± 3.0(stat) +1.0-1.9(syst) % • AC (theory) = 1.3% • t-tbar mass difference • Muon+jets channel • Kinematic fit to the mass of the hadronically decaying top • Ideogram method • Likelihood calculated for each event to be consistent with mt • Ideogram method applied separately to μ++jets and μ-+jets • Δm(t-tbar) = -1.20±1.21(stat)±0.47(syst) GeV Exceed’s Tevatron precision LHCC CMS Status Report -- D. Acosta

  13. Search for Bs(d) μμ, 1.1 fb-1 arXiv 1107.5834accepted by PRL • Decays are highly suppressed in the SM • BR(Bsμμ): (3.2±0.2)x10-9, Bdμμ: (1.0±0.1)x10-10 • Indirect sensitivity to new physics • MSSM: BR∝(tanβ)6 • Blind analysis • B+ J/ψ K+ used for normalization • B0 J/ψ ϕ used as control regions for efficiencies • Events observed in the unblinded windows are consistent with bkg. plus SM expectations. • CMS BR Limits at 95% CL • Bsµ+µ− < 1.9×10−8 • Bdµ+µ− < 4.6×10−9 LHCC CMS Status Report -- D. Acosta

  14. CMS + LHCb Combination Bs μμ • CMS BR Limit • Bsµ+µ− < 1.9×10−8 • LHCb BR limit • Bsµ+µ− < 1.5×10−8 • Combination of LHCb+CMS: • Bsµ+µ− < 1.08×10−8 • The value of CLs is in good agreement with background + SM LHCb-CONF-2011-047 CMS PAS BPH-11-019 LHCC CMS Status Report -- D. Acosta

  15. The Higgs See also the CERN seminar given by M.Zanetti on Sept.12

  16. Overview of Searches • Light Higgs • Hbb • Hττ • Hγγ • HWW • HZZ4l • Medium to Heavy Higgs • HWW2l2v (+jets) • HZZ (2l2j, 2l2v, 4l, 2l2τ) LHCC CMS Status Report -- D. Acosta

  17. Hbb, 1.1 fb-1 PAS HIG-11-012 • Search strategy: • Associated production with W/Z • Boosted W/Z topology, withH back-to-back with W/Z • 2 b-jets (~10% mass resolution) • 5 topologies: • WH  μvbb, evbb • ZH  μμbb, eebb • ZH  vvbb • Two complementary analyses: • Cut and count in Mbb • MVA with boosted decision tree • Yields are in good agreementwith data-driven backgroundestimates BDT analysis LHCC CMS Status Report -- D. Acosta

  18. Hγγ, 1.7 fb-1 PAS HIG-11-021 • Strategy • 2 isolated γ’s with PT>40, 30 GeV • Data divided into 8 categoriesdepending on resolution and pT(H) • σeff(mass) varies from 1.4 – 7.9 GeV • Background shape fitted by2nd order polynomial in each category • Signal energy resolution extractedfrom Zee data MC for illustration only LHCC CMS Status Report -- D. Acosta

  19. Hτau τau, SM and MSSM, 1.1-1.6 fb-1 PAS HIG-11-020 • SM categories • VBF: 2 jets with Δη>3.5, mjj>350 • Non-VBF: <2jets or 2 failing VBF tag • MSSM categories • B-tag: ≥1 b jet pT>20 • Non-b-tag: <2 jets and no b-tags • Topologies • μτh, eτh, eμ (1.6 fb-1), μμ (1.1fb-1) • τh ID by “hadron plus strips”, 6% efficiency uncertainty • Fit visible mass distribution LHCC CMS Status Report -- D. Acosta

  20. Hτau τau, MSSM Exclusion LHCC CMS Status Report -- D. Acosta

  21. HWW2l2v, 1.6 fb-1 PAS HIG-11-014 EWK-11-010 • 2 isolated leptons, large MET,no b-tags (to suppress top) • 3 categories • 0, 1, 2 jets (VBF) • No mass peak • Kinematic discrimination byMll and Δϕll , exploiting scalar decay Exclude 147–194 GeV @ 95% CL (130-200 expected) σ(ppW+W-+X)= 55.3 ± 3.3(stat.)±6.9(syst.)±3.3(lumi) pb σ(NLO)=43±2pb LHCC CMS Status Report -- D. Acosta

  22. HZZ 4l (l=e,μ 1.7 fb-1), 2l2τ (1.1 fb-1) • “Golden” decay mode • 4l mass resoln. is O(2-3) GeV σ(ppZZ+X)= 3.8+1.5-1.2(stat.)±0.2(syst.) ± 0.2(lumi) pb σ(NLO)=6.4±0.6pb PAS HIG-11-015, 013 EWK-11-010 LHCC CMS Status Report -- D. Acosta

  23. HZZ 2l2v, 2l2j PAS HIG-11-016, 017 • ZZ2l2v • Zll • Large MET • No b-tag jets • MT (2l2v) window • ZZ2l2j • Likelihood discriminant based on angular correlations • 4 categories based on # b-tags, and a quark/gluon discriminant CMS Preliminary LHCC CMS Status Report -- D. Acosta

  24. Summary of all Searches PAS HIG-11-022 • Solid lines: observed limits @ 95% CL • Dashed lines: expected limits Σ (all this work)  LHCC CMS Status Report -- D. Acosta

  25. SM Higgs Combination PAS HIG-11-022 • Disfavoured mass region for minimal SM Higgs: • Expected: 130 – 440 GeV • Observed: 145-216, 226-288, 310-400 GeV LHCC CMS Status Report -- D. Acosta

  26. Higgs with 4 Fermion Generations, 1.1 fb-1 PAS HIG-11-011 • Combination of analyses • Heavy 4th fermion generation coupling to SM Higgs disfavoured over mH=120—600 GeV @ 95% CL LHCC CMS Status Report -- D. Acosta

  27. SUSY

  28. Overall Search Strategy • Inclusive topologies not tied to specific models, typically but not always with assumption of MET (dark matter) • Generally several approaches within each category, as well as several search regions • Additionally add b-tagging to some categories • Targeting strongly produced squarks and gluinos • Establish data-driven estimates of backgrounds (With Z+MET) (And γ+MET) High yield, high bkgnds.  Rare, low bkgnds. LHCC CMS Status Report -- D. Acosta

  29. 0 Lepton: new search using MT2, 1.1 fb-1 PAS SUS-11-005 • “Stransverse” mass: • Extension of transverse mass totwo undetected particles (LSPs) • Endpoint corresponds to particle masses • Used here as a discovery discriminant for SUSY: MT2~0 for fake MET, MT2~MET for signal • Two signal regions (high MT2, low MT2 + b-tag) X1 X2 MT2>400 Nj ≥ 3 LHCC CMS Status Report -- D. Acosta

  30. 0 Lepton: “αT” Approach, and traditional jets+MET, 1.1fb-1 Nj≥2, HT>375 • QCD dijets have edge at 0.5  • Processes with real MET have tail above 0.5 • Events with >2 jets are clustered into 2 pseudo-jets • Perform shape analysis of vs. HT • Traditional jets + MHT • ≥3 jets and 3 signal regions in HT (500, 800)and MHT (350, 500) • No excess observed over data-driven bkgds. arXiv:1109.2352 PAS SUS-11-004 ) (n.b. MHT LHCC CMS Status Report -- D. Acosta

  31. Single Lepton Search, 1.1 fb-1 PAS SUS-11-015 • Exactly 1 isolated lepton pT>20 (e or μ), ≥3-4 jets, large MET and HT • Two approaches to define signal regionsand to measure backgrounds • Use relationship between lepton pTspectrum and MET (in SM) to predict bkgnd. with HT > 500  • Use helicity structure of V-A coupling to W Total bkg Consistent with SM.Similar limits achieved in both approaches LHCC CMS Status Report -- D. Acosta

  32. Same Sign Dileptons, 1 fb-1 PAS SUS-11-010 • Clean signature with low SM bkgnds. • Consider ee, eμ, μμ, eτh, μτh, τhτh • Complementary baseline selections, used to check bkgnd predictions • Inclusive SS dileptons with HT>200 • High PT SS dileptons with HT>80 • Dileptons with τh and HT>350, MET>80 • Define several search regions per selection with tighter cuts on HT and MET: High PT Inclusive and τh LHCC CMS Status Report -- D. Acosta

  33. Putting it all Together in CMSSM LHCC CMS Status Report -- D. Acosta

  34. Summary in Several Simplified Models T1 T2 T1lnu T5zz LHCC CMS Status Report -- D. Acosta

  35. GGM SUSY: Photon(s) + MET, 1.1 fb-1 PAS SUS-11-009 • Diphoton search for general gauge mediated SUSY with the gravitino as the LSP, extended to single photons • Two topologies with large MET • 2 or more isolated photons ET>45, 30 and 1 jet • 1 isolated photon ET>75, ≥3 jets • Backgrounds without real MET(QCD with fake γ’s) from data Di-γ LHCC CMS Status Report -- D. Acosta

  36. Other Exotica

  37. Dilepton Resonance Search,1.1 fb-1 PAS EXO-11-019 • Search for new gauge bosons or new symmetries (EDs) yielding high mass narrow dilepton resonances (ee, μμ) • 95% CL mass limits: Upper limit on the ratio of Z’ or GKK to SM Z production LHCC CMS Status Report -- D. Acosta

  38. W’ Gauge Boson Search, 1.1 fb-1 PAS EXO-11-024 • Isolated single electrons, muons W’ with SM couplings excluded @ 95% CL with mass below 2.27 TeV e e μ μ combined LHCC CMS Status Report -- D. Acosta

  39. Dijet Resonance Search, 1.0 fb-1 arXiv:1107.4771 • Search for new narrow resonances in the dijet mass spectrum • Templates based on qq, qg, and gg final states • Utilize wide jets to recover radiation (ΔR<1.1) • 95% CL mass limits: LHCC CMS Status Report -- D. Acosta

  40. tt Resonance Search in Boosted Hadronic State, 0.9 fb-1 PAS EXO-11-006 • Search for heavy resonances (Z’) decaying to top pairs in boosted regime • Classify boost of hadronic decay: • Merged into single jet • 2 out of 3 jets merged • Search for types 1+1 and 1+2 • 2 algorithms to tag merged jets using C-A algo with R=0.8 using mjet, # subjets, etc. • Particle flow inputs Type 2 Type 1 Using l+jets sample  LHCC CMS Status Report -- D. Acosta

  41. Vector-like Top Quark and 4th Generation • Tt Z • Search for FCNC decay of a heavy quark T t Z0 • If vector-like, as in Little Higgs theories, could have large BR • Full topology: • Search for Z(ee or μμ) + additional lepton + at least 2 jets • m(T) > 475 GeV @ 95% CL • b’tW • Search for trileptons or same-sign leptons, + b-jet • m(b’)>495 GeV @ 95% CL • t’bW • l+jets: Search for isolated e/μ, large MET, ≥4 jets, b-tag • Dileptons: (ee, eμ, μμ), MET, ≥2 jets, 2 b-tags • m(t’)>450 GeV (l+jets), 422 GeV (dilep) PAS EXO-11-005 PAS EXO-11-036, 050, 051 LHCC CMS Status Report -- D. Acosta

  42. Exotica Grand Summary 95% CL exclusion limits TeV TeV LHCC CMS Status Report -- D. Acosta

  43. Summary • These are definitely NOT austere times for our science! • A very rich physics program has opened up with the first inverse femtobarn from the LHC ! • A broad set of tools and strategies have been developed • SM • Reaching precision era, confronting predictions • Higgs • No evidence yet, although wide mass regions for minimal SM Higgs are becoming disfavoured at 95% CL (also heavy 4th generation fermion coupling) • SUSY and Exotica • Sensitivity to squark and gluino masses in range 0.5 – 1 TeV • Many resonant/non-resonant signals sought • It is a challenge to keep pace with the LHC, but it’s also a very nice situation to be in. Exciting times! • Thanks to CERN and the LHC team ! LHCC CMS Status Report -- D. Acosta

  44. Backup LHCC CMS Status Report -- D. Acosta

  45. Electroweak: Dibosons (WW, WZ, ZZ), 1.1fb-1 PAS EWK-11-010 • Measure backgrounds to high mass Higgs search • Test for anomalous TGCs • WW (ee,eμ,μμ) • Jet and soft b-tag veto • Use MET transverse to closest lepton • WZ (eee,eeμ,eμμ,μμμ) • ZZ4l (l=e, μ, or τ) WW WZ σ(NLO)=43±2pb σ(ppW+W-+X)= 55.3 ± 3.3(stat.)±6.9(syst.)±3.3(lumi) pb; σ(ppWZ+X)= 17.0 ± 2.4(stat.)±1.1(syst.)±1.0(lumi) pb; σ(ppZZ+X)= 3.8+1.5-1.2(stat.) ± 0.2(syst.) ± 0.2(lumi) pb; σ(NLO)=19.8±0.1pb σ(NLO)=6.4±0.6pb LHCC CMS Status Report -- D. Acosta

  46. Hbb Combined Limits, 1.1fb-1 PAS HIG-11-012 BDT analysis Mbb analysis LHCC CMS Status Report -- D. Acosta

  47. Local significances and combination CMS PAS 11-022 • p-value estimates probability of upward background fluctuation as high or higher than the excesses observed in data • Global p-value estimated to be ~0.4 LHCC CMS Status Report -- D. Acosta

  48. Dilepton Resonance Search,1.1 fb-1 PAS EXO-11-019 • Search for new gauge bosons or new symmetries (EDs) yielding high mass narrow dilepton resonances • Relatively clean final state LHCC CMS Status Report -- D. Acosta

  49. Combined Dilepton Limits, 1.1 fb-1 PAS EXO-11-019 Upper limit on the ratio of Z’ or GKK to SM Z production • 95% CL mass limits: LHCC CMS Status Report -- D. Acosta

  50. WR and Heavy Neutrino Search, 0.24 fb-1 PAS EXO-11-002 • L-R symmetric extension to SM with parity spontaneously broken • Generates WR and Z’ bosons plus heavy RH neutrinos • Search for resonance structure in ljj and lljj • Impose cuts m(ll)>200 and m(lljj)>520 • Search in 200 GeV wide bins LHCC CMS Status Report -- D. Acosta

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