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Top A FB from Heavy New Physics Model Independent Lessons

Top A FB from Heavy New Physics Model Independent Lessons. Cédric Delaunay Weizmann Institute of Science Israel Phys.Lett.B702:364-369,2011 & JHEP 1108:031,2011 in collaboration w/ the Weizmann dreamteam : K. Blum, O. Gedalia , Y. Hochberg ,

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Top A FB from Heavy New Physics Model Independent Lessons

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  1. Top AFBfromHeavy New PhysicsModel Independent Lessons Cédric Delaunay Weizmann Institute of Science Israel Phys.Lett.B702:364-369,2011 & JHEP 1108:031,2011 in collaboration w/ the Weizmann dreamteam: K. Blum, O. Gedalia, Y. Hochberg, S.J. Lee, Y. Nir, G. Perez & Y. Soreq August 31, 2011 | CERN

  2. Tevatron Data Basic fact:o(5) AFBmeasurementsdifferfrom SM: CDF: l+j & ll (incl+diff)| DØ: l+j (incl) & lep AFB whileXsec(incl+diff)is consistent withit. Kamenik et al. ‘11 O(1) effects, more pronounced @higherenergies New Physics ?? Ahrens et al. ‘10 Westhoff ‘11

  3. New PhysicsInterpretation • Let’s assume experiments are correct itis new physics • zerothorderlessonsfromO(1) NP effects in tt production: • strong production • tree-level(i.e. LO QCD) • mustinterfere w/ SM source if not, >2σ tension with data! • 2 paths to explain data: • light NP | ΛNP < TeV • heavy NP | ΛNP > few TeV (w/ stronger NP couplings) • this talk focuses on the latter AFB & Xsec fit (mtt>450GeV) Grinstein et al. ‘11

  4. Blum et al. ’11 Delaunay et al. ‘11 Heavy NP & EFT approach • effective operators relevant to qq tt transitions @highmtt above 450GeV, q≈u(dd/uu≈20%, whichweneglecthere) non SM-like NLO corrections alsoneglected(thisispQCDafter all) o(Λ2) : o(Λ4) : none (if NP couplings to qq/tt are strong) (in the perturbativesense, seelater) interfere w/ SM gluon production don’tinterfere w/ SM

  5. Heavy NP & EFT approach Blum et al. ’11 • o(mtt2/Λ2) effects:  SM • CDF AFB(mtt>450) ≈ 50%cA8 ≈ 2.4/TeV2 So far, welearnthat: • sinceΛ>1-2TeV, NP couplings are sizable, at least o(1) • fromperturbativityΛ<4π/√2.4≈8 TeV • Implications for other observables | 1sthintsfrom(OA8)2 • boosted top excess @CDF (Alon et al ’10 | seealsoGilad’s talk) AFBimpliesNP/SM ~ 2 ≈ observed - 1σ • enhancement of the tt-tail @LHC again, AFBimpliesNP/SM ~ 5@mtt= 1.5TeV (cV8 = 0, sothatXsecis ok) thereis a regionwhere EFT expansion makessense.

  6. Heavy NP & EFT approach Delaunay et al. ‘11 • o(mtt4/Λ4) effects: all (4f-operators)2 kinematicaldiff. ~ 4mtop2/mtt2≈ o(20/50%) for mtt=800/450GeV , but furthersuppressed (if not vanishing) whenAFBismaximazed. • If neglected, a simple polar basis for non-interferingopsemerges withinwhich NP/SM Xsec ratio & top AFB read: • Now, one canstart do physics&drawgenericlessons about heavy NP as a explanation of AFB anomalies. a,b,d,e,α,β = kinematical #’s

  7. Model Independent Lessonsfrom EFT Delaunay et al. ‘11 AFB>450~50% & NP/SM diff-Xsec < 1σ welearnthat: [c]=[R]=TeV-2 • cA8 > 0.3/TeV2 (recall NP must interfere) • R < 3.1/TeV2 • single chiral operatorcan’treproduceAFB (θ=0) Implications for LHC tt-tail smoking gun: NP/SM > 2 @1.5TeV (LHC verdict availablesoon…?)

  8. Last words • implication for boosted tops @CDF: AFB w/in 1σimpliesNP/SM>50% • dijets production @LHC? • fromqqttit self via loop: ok! • @tree-levelfromqqqq: ok, provided NP couplingsgqq/gtt<1/5 ! • any questions?

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