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ATLAS SUSY review (missing momentum)

ATLAS SUSY review (missing momentum). Alan Barr On behalf of ATLAS. https:// twiki.cern.ch/twiki/bin/view/AtlasPublic/SupersymmetryPublicResults. 1 pb. 1 fb. Integrated luminosity: 2 fb -1 (Mid 2012) 5 fb -1 (All of 2011). Missing momentum ( E T miss ) signatures: challenges in 2011.

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ATLAS SUSY review (missing momentum)

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  1. ATLAS SUSY review(missing momentum) Alan Barr On behalf of ATLAS https://twiki.cern.ch/twiki/bin/view/AtlasPublic/SupersymmetryPublicResults

  2. 1 pb 1 fb Integrated luminosity: 2 fb-1(Mid 2012) 5 fb-1(All of 2011)

  3. Missing momentum (ETmiss) signatures: challenges in 2011 Data collectedInt. Lumi: ~5 fb-1 • Instantaneous luminosity: 3.65×1033 cm−2s−1 • Trigger: ETmiss-only trigger: threshold up to 180 GeV • Others available • Pile-up: up to • Calorimeter response (in-time and out-of-time) • Jet and ETmissresolution • Particle ID

  4. Pile-up: track ↔ jet association A spectacular 9-jet + ETmiss eventAll nine jets associated to same primary vertex(even in presence of many other vertices)

  5. Analysis philosophy * We have some fast-sim for signal Dedicated analysis for different final states State of the art Monte Carlo Validated GEANT-4 detector simulation* Multiple redundant control regions (CR) Multiple cross-checks & validation regions (VR) Appropriate kinematic & ID variables Uncertainties based on measurements wherever possible Signal systematics in limits

  6. Try to make it simple…

  7. Jets: anti kT, R=0.4, emhad calibration B-tagged jets: secondary vertex fitter Typically at point: (εB~60%, εlight<1%) Leptons (either e or µ), isolated Trigger requires: (e > 25, µ > 20), soft lep down to (7,6) GeV Tau: 1- or 3- prong hadronic pT > 20GeV Photon: isolated ? ETMiss: Missing transverse momentum -ve sum pT of: jets, leptons, unclustered ET Disappearing track LEGEND

  8. ATLAS-CONF-2012-034 ATLAS-CONF-2012-033 arXiv:1203.5763 ATLAS-CONF-2012-037 ATLAS SUSY review: missing momentum ATLAS-CONF-2012-003 2 fb-1 ATLAS-CONF-2012-036 arXiv:1112.3832 ATLAS-CONF-2012-023 ATLAS-CONF-2012-041 2 fb-1 5 fb-1 ArXiv:1111.4116 1fb-1 ATLAS-CONF-2012-001 ATLAS-CONF-2012-005 ATLAS-CONF-2012-002 ATLAS-CONF-2011-096 ?

  9. ATLAS-CONF-2012-034 ATLAS-CONF-2012-033 ATLAS-CONF-2012-037 ATLAS-CONF-2012-041 5fb-1 Full 2011 dataset ?

  10. ATLAS-CONF-2012-033 No leptons, ≥(2-6) jets + ETmiss Squarks, Gluinos Page 10

  11. ATLAS-CONF-2012-033 Small Δm Gluinos/cascades Squarks Different mass scales Total of 11 signal regions

  12. ATLAS-CONF-2012-033 Control regions for each significant BGMultijet BG determined from data-driven smearing method Smaller backgrounds, e.g. diboson: MC only

  13. ATLAS-CONF-2012-033 meff (incl.): scalar sum of ET of all jets and ETmiss MC scaled by ~0.75 (based on control regions)Band shows JES, JER, MC stats

  14. ATLAS-CONF-2012-033

  15. ATLAS-CONF-2012-033 Non-disjoint SRs: exclusion based on best expected significance MSUGRA/CMSSM Simplified gluino-squark-neutralino model

  16. ATLAS-CONF-2012-041 1-lepton + jets + ETmiss Strong  chargino neutralino Page 16

  17. Chargino cascade decays etc: One-lepton Small Δm ATLAS-CONF-2012-041

  18. 1-lepton: background determination ATLAS-CONF-2012-041 Control & validationregions • Control regions split by jet multiplicity (up to 9 jets) • Nuisance parameters fitted • B-tagging • kTfact (Alpgen) • Normalisations • Over-constrained system

  19. Control regions – jet multiplicity ATLAS-CONF-2012-041

  20. 1-lepton results ATLAS-CONF-2012-041 Fit allows different backgrounds to adjust, based on CR(Also relative fraction of different multiplicities in Alpgen)

  21. Significantly improved ATLAS-CONF-2012-041 3j, 4j signal regions statistically combined (first time) Shape of meff used when making exclusion (6 bins 4001600 GeV)

  22. Simplified model limits ATLAS-CONF-2012-041 Hard lepton analyses Soft lepton analysis Near-degenerate region: gain factor of 20-30 from soft lepton

  23. ATLAS-CONF-2012-037 No leptons ≥(6-9) jets + ETmiss Gluinos cascadesGluinos 4 x tops Page 23

  24. ATLAS-CONF-2012-037 QCD background: stochastic term  HT Independent of jet multiplicity • Final variable quantifies significance of Etmiss •  Multi-jets dominated control regions •  Subtract (subdominant) “leptonic” backgrounds • QCD background is reliably predicted (~20%) • Tested in further control regions and cross-checked with jet-smearing method

  25. ATLAS-CONF-2012-037 SR: 7j80 Top validation region SR: 9j55

  26. ATLAS-CONF-2012-037 Most discrepant 7j80 p-value 0.07

  27. ATLAS-CONF-2012-037 arXiv:1203.5763 ATLAS-CONF-2012-003 Simplified gluino/top model

  28. ATLAS-CONF-2012-033 ATLAS-CONF-2012-037 ATLAS-CONF-2012-041 5 fb-1 MSUGRA/CMSSM interpretation Gluino mass > ~850 GeV

  29. ATLAS-CONF-2012-034 ATLAS-CONF-2012-033 arXiv:1203.5763 ATLAS-CONF-2012-037 ATLAS-CONF-2012-003 2 fb-1 ATLAS-CONF-2012-036 2 fb-1 ArXiv:1112.3832 ATLAS-CONF-2012-023 ATLAS-CONF-2012-041 5 fb-1 ArXiv:1111.4116 1 fb-1 ATLAS-CONF-2012-001 ATLAS-CONF-2012-005 ATLAS-CONF-2012-002 ATLAS-CONF-2011-096 ?

  30. arXiv:1203.5763 2 fb-1 ATLAS-CONF-2012-023 ATLAS-CONF-2012-001 ATLAS-CONF-2012-005 ATLAS-CONF-2012-002 EW gauginos, staus

  31. Three-lepton + ETmiss ATLAS-CONF-2012-023 Direct EW gaugino

  32. Three-lepton + ETmiss Searches for direct gaugino productionChargino + neutralino 3 leptons + 2 LSP OSSF pair(s) allowed (mll > 20) ATLAS-CONF-2012-023 pT (µ) > 20,10,10 GeV pT (e) > 25,10,10 GeV ETmiss> 50 GeV Z enriched(within 10 GeVof mZ) Z depleted(+b jet veto)

  33. 3-lepton + Etmiss - gauginos Via slepton ATLAS-CONF-2012-023 LSP Chargino-1

  34. ATLAS-CONF-2012-035 ATLAS-CONF-2012-001 4 lepton + ETmiss Direct gauginos L-violating RPV

  35. ATLAS-CONF-2012-035 ATLAS-CONF-2012-001 L-violating RPV  LSP λ121gut ~ 0.032

  36. ATLAS-CONF-2012-005 ATLAS-CONF-2012-002 ≥1 tau or ≥2 taus + Jet(s) + ETmiss GMSB, stau NLSP

  37. Final states with taus Expect: 5.3 ±1.3(stat)±2.2(sys) Observe: 3 Jet (130) + ETmiss (130) trig. mEff > 700 GeV mT(1) + mT(1) > 80 GeV ε(1p) ~ 30% ε(j) ~ 0.5% ε(3p) ~ 50% ε(j) ~ 3% Same trig mEff> 600 GeV mT(1) > 110 GeV ATLAS-CONF-2012-002 ATLAS-CONF-2012-005

  38. ATLAS-CONF-2011-156 2 fb-1 ATLAS-CONF-2012-002 ATLAS-CONF-2011-156 ATLAS-CONF-2012-005 1fb-1

  39. ATLAS-CONF-2012-003 2 fb-1 ATLAS-CONF-2012-036 arXiv:1112.3832 arXiv:1111.4116 ATLAS-CONF-2011-096 1 fb-1

  40. ATLAS-CONF-2012-003 b-jet(s) (+ 1 lepton) + jet(s) + ETmiss Gluino Sbottom/Stop

  41. B jet(s) (+ 1 lepton) + jet(s) + ETmiss ATLAS-CONF-2012-003

  42. ATLAS-CONF-2012-003 1-electron ≥1 b-tag 0-lepton ≥2 b-tags

  43. ATLAS-CONF-2012-003 1-lepton (MC yields in parentheses) 0-lepton

  44. ATLAS-CONF-2012-003 Virtual sbottom Real sbottom

  45. arXiv:1112.3832 2 jets only(veto on third jet) Direct sbottom

  46. Direct sbottom 2 jets only – veto on third jet ArXiv:1112.3832 (Pure MC predictions in parentheses)

  47. Direct Sbottom 2 jets only – veto on third jet ArXiv:1112.3832

  48. ATLAS-CONF-2012-036 b-jet, same flavour, opposite sign leptonsmll ~ mZ Direct Stop pair  Hino  LSP + Z

  49. Etmiss > 50 GeV 80 GeV ATLAS-CONF-2012-036 SR2 SR1 1 pair production 1 t + Decays via sbottom, h also included

  50. ATLAS-CONF-2012-034 Finally… Disappearing track ? Light winos, AMSB

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