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Tevatron Physics Results – Implications for the LHC *

Tevatron Physics Results – Implications for the LHC *. Paul Grannis, for the CDF and D Ø collaborations ATLAS Physics Workshop, Aug. 3 2009. * What about dem Mets?. Operations.

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Tevatron Physics Results – Implications for the LHC *

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  1. Tevatron Physics Results – Implications for the LHC* Paul Grannis, for the CDF and DØ collaborations ATLAS Physics Workshop, Aug. 3 2009 * What about dem Mets?

  2. Operations • Fermilab expects to run the Tevatronthrough FY2011. The Tevatron is now delivering close to its upper projection L. 90% DØ efficiency to tape (93% in April). 80% of total delivered gets into analyses. now Summer ’09 results up to 5.8 fb-1, typically ~ 4fb-1 Expect 12 fb-1 delivered; 10 fb-1 to physics • Detector subsystems should (almost) survive for 12 fb-1 of data. (DØ silicon shown here; Layer 0 is OK; inner detectors on layer 1 barrel not fully depleted after ~9 fb-1.) 2

  3. Physics output Publications by year CDF + DØ Now ~100 papers/year. Recent results based on 3–5 fb-1 so final data set will be 2–3X current. Many analyses still improving faster than 1/L1/2 due to improvements in techniques No further upgrades to detectors; triggers are now stable. • Physics analyses in CDF and DØ based in six working groups: • Top quark properties • Electroweak bosons • Heavy flavor (b,c) states • Searches for phenomena beyond the SM • QCD studies • Higgs boson searches This talk will select only some highlights of interest to initial LHC program (and those that will be Tevatron legacy). Many results will be updated for Lepton Photon. CDF and DØ are now taking students (~10/expt) who did ATLAS/CMS hardware and commissioning to do Tevatron physics analyses for theses. A good match! 3

  4. Top quark Top quark mass: Tevatron average Mt=173.1±1.2 GeV (0.7%) Have now exceeded the Tevatron goal; expect the final average mass to be below 1 GeV. Are now reaching the systematic limit (heavy flavor jet energy scale, signal model, jet resolution). Reaching this precision will take LHC experiments a while. Best single top-antitop cross section measurement (CDF) is ±8% and uses the Z cross section to reduce normalization uncertainty. Consistent with theory for the measured Mt. Final systematic limit should reach ~6%, less than the 10% theory error. 4

  5. DØ preliminary f0 SM NLO QCD DØ *t-t spin correlations: (ds/dz1dz2=1/4(1-Cz1 z2); zi=cosqi of lepton i in top rest frame) In NLO QCD, C=0.777. C=0.32 (CDF). DØ is 2sfrom QCD. +0.55 -0.78 Top properties W helicity in t decay: p=23% to see larger SM discrepancy than observed. With 8 fb-1 and same central value, p=0.0024. * AFB=0.193±0.069 (3.2 fb-1) (NLO QCD: 0.05±0.015) Top-antitop mass difference 3.8±3.7 GeV Top charge = 4e/3 excluded at 92% CL t t resonance excluded to 820 GeV. (Are already into LHC regime where jets from boosted tops merge, so kinematic fitting is not optimum.) All statistics limited; hints of non-SM behavior exist so stay tuned. ( * = Tevatron legacy) Hint of t’ quark? 5

  6. EW single top production s-channel W*tb t-channel W*b*t Final state is tb = bbW • Signal is small; background is large. Analyses pull all the stops (BDT, BNN, ME, L fns). Both CDF/DØ now at 5s (3.2/2.3 fb-1). Analyses are statistics limited. • New result: 4.8s significance for t channel process alone. Separate s- and t-channel XS; sensitive to BSM physics +0.94 -0.81 st = 3.14 pb • With full data set: • Expect dVtb/Vtb ≈ 0.08 • Sensitive to W’ > 800 GeV • H± search with MH > Mt • Anomalous top couplings Combining W helicity and single top 6

  7. MW top error W error Mt W boson mass Recent DØ measurement (1 fb-1) gives MW=80.401±0.043 GeV (CDF 80.413±0.048 GeV in e & m, 0.2 fb-1). Requires control of systematics to 10-4 level (energy scale, recoil system calibration, QED/QCD modeling). Precision is statistics limited (mainly Z statistics) so will improve. ultimate Expect 2009 Tevatron (World) average MW with errors ≈31 (23) MeV. (Tevatron dM < LEP dM) With 10 fb-1, expect error ~16 MeV/expt (~12 MeV combined), so world average dMW≈10 MeV. This will be a challenge for LHC experiments to match! But the overconstraint on SM with LHC Higgs will be very strong. ultimate 7

  8. W/Z measurements • ds/dpTZ measures QCD resummation parameter g2 and is needed to reweight MC backgrounds for rare processes. • New direct measurement of W± asymmetry: more precise than current PDF errors, so will constrain future PDF fits. • AFB for qq  Zg*  ll measures sin2qW for light quarks (recall the LEP/SLC discrepancy between sin2qW for leptons and heavy quarks). With 10 fb-1, will have comparable precision for light quarks as LEP/SLD for b-quarks. AFB at high mass probes new physics. • Direct measurement of W boson width from high transverse mass tail; now WA uncertainty with 1 fb-1 of ~45 MeV. Project WA after 10 fb-1 ~20 MeV (better than the current indirect measurement from W/Z sxBR ratio of 42 MeV) 8

  9. Diboson cross sections At Tevatron, Wg, Zg, WW, WZ, ZZ processes have the smallest SM cross sections apart from Higgs. With the DØ 5.7s observation of ZZ last summer, all have now been observed. • The diboson processes are important for several reasons: • Search for anomalous trilinear couplings (here LHC will do much better) • They are backgrounds for even rarer processes (EW production of top, Higgs, …). Give experimental guidance on NLO/LO k-factors. • Demonstration of techniques for Higgs search using a ‘known’ rare process. Diboson measurements are dominated by statistics, so increase in data samples will help considerably. dijet mass in 2 jet+missing ET (1st observation of WW,WZ,ZZ in semihadronic channel.) CDF 3.5 fb-1 9

  10. ± BS→ J/yf, BS → DSm± charge asymmetry; dimuon charge asymmetry (m+m+ vs. m-m-); time dependent BS → DS-m+X will all provide further constraints on fS: More data, use of multiple analyses, and improved event selection and BS – BS tagging can give significant non-SM indication. If current central value holds, can reach 5s discovery on non-SM physics. CP in BS system CDF+DØ combined see 2.0s deviation from SM in joint fit of DGS vs. fS for BS→ J/yf thus hinting at new phenomena beyond the SM. DGS = GL – GH = 2|G12|cosfS bS = -2fS fS= fSSM + fNP fSSM=-0.04 ± 0.01 MeasurefS= -0.76 rad(BS J/yf) +0.37 -0.33 Projection for BS→ J/y fonly, 1 exp’t and no projected improvements. 10

  11. b-quark physics August 2008 CDF 4.2 fb-1 • Tevatron produces heavy b-quark hadrons inaccessible at B-factories: • Have added to Lb(udb) seen by UA1: Sb± (uub, ddb), Xb(dsb), Wb(ssb) (CDF & DØ Wb masses do not agree) • Extensive studies of BC, BS mesons M=6165±16 MeV M=6054.4±6.9 MeV Increased statistics will improve mass, lifetime measurements, BS mixing,. All are important for confronting HQETpredictions and understanding non-pQCD. Rare b-hadron decays probe new non-SM physics. In MSSM, BS→mm rate is enhanced by tan6b. Expect ~10xSM per experiment (10 fb-1). M(mmKK)-M(mm) And new surprises continue: evidence for ‘charmonium’ state Y(4120) J/Y f  mmKK 11

  12. Searches for new phenomena Neutralino/chargino search in trileptons CDF and DØ have searched for many states expected in Susy, strong coupling, large extra dimension models with no clear signals to date. Squark search in jet + t + MET ~ Search for c10 in GMSB with c10 G g. Approaching the cosmologically favored region. CDF RS graviton  ZZ 12

  13. Searches for new phenomena MSugra limits are improving beyond LEP limits, due to high statistics and new techniques. For example We are gratified with these improvements … … but we hear the locomotive coming on the tracks behind us, and look forward to some real news on SUSY soon. 13

  14. New phenomena • Now searching in new model contexts. • In NMSSM, new light a states, with h  aa(amm, tt)that defeat the SM Hbb search limits. HyperCP saw a hint of a 214 MeV “a” boson in Spm+m-. With full Tevatron sample, can exclude the NMSSM in much of the allowed range. • Hidden valley models postulate a hidden sector weakly coupled to SM. SM Higgs couples to HV higgs pHV with couplings that could be large: pHVbb. Get limits as f(MH, MpHV, decay length). Now exclude for small MHV, DL. Neutralino can decay to HV “dark photons” and “darkino” with gDARK lepton jets. Searches now begin to exclude regions of phase space. 14

  15. QCD studies Inclusive jet production to very large pT and rapidity, favoring lower gluon content at large x. Studies of pQCD and non-p QCD have extended HERA and LEP measurements. The detectors and algorithms are now well calibrated. Techniques and PDF constraints are valuable for early LHC running. ds/dc distributions (would be flat for Rutherford scattering) are sensitive to new physics contributions. New limits set on quark compositeness, RS extra dimensions, ADD extra dimensions. DØ data ds/dMjj distributions at high mass and large rapidity constrain PDFs. Data/theory ratio now distinguishes CTEQ6 and MSTW predictions. 15

  16. Z+jets production W/Z+jets production is an important test of QCD, and is a major background for top quark studies and many searches such as Higgs bosons & trilinear gauge boson couplings. LHC analyses will require good understanding of these. Recent studies of Z+jets, unfolded from pTjet(meas) to pTjet(true) to confront predictions with various event generators. Jet cone (R=0.5) is used. Meas vs true pT migration matrix pTjet yjet pTZ yZ These comparisons generally show agreement within errors for NLO pQCD (for pTZ > 45 GeV). ALPGEN shapes are OK, but normalizations are off. SHERPA and PYTHIA have shape disagreements. Z+b jet measurements are key inputs for many searches; now being measured at the Tevatron. 16

  17. SM Higgs boson Low mass Higgs (MH < 135 GeV): mainly sought in associated WH/ZH production; high mass (MH > 135) mainly in gluon-gluon fusion: March 2009 combination channels WH: e/mn bb t n bb qq’ tt e/m n W(e/m)W(e/m) jj bb ZH: ee/mm bb nn bb tt bb qq tt ttH: lnb qq’b bb gg→H:W(e/m)W(e/m) gg tt (+ 2 jets) WW →H: tt (+ 2 jets) Mar. 2009: next update at Lepton Photon 17

  18. SM Higgs boson Direct Higgs search confronts the SM indirect measurement allowed region. The advanced multivariate and statistical techniques used for the W/Z +H search are now verified in the similar W(ln) W/Z(qq) production. Measure 20.2±4.4 pb (16.1±0.9 SM) : 4.4s significance. Would like to extend this to W(ln) Z(bb) to also test b-tagging and lower signal/background ratio. 18

  19. 10 fb-1 SM Higgs boson • Improvement faster than L-1/2 • better b-tagging • lepton ID improvements • more channels • better background models • larger kinematic regions • jet E resolution improve With 10 fb-1 analyzed, expect to be able to rule out SM Higgs to >180 GeV, and have shot at evidence below ~120 GeV. Probability for 3s evidence in 10 fb-1. 19

  20. SUSY Higgs Previous searches for Susy higgs were in separate channels. The sensitivities of these are comparable h  tt hb  bbb hb  btt New combined limit from all three processes – 1 – 2.6 fb-1 Closing the gap on low mA Susy higgs in the interesting region (tanb ~ 35-40) where tanb ≈ mt/mb 20

  21. Conclusions • We expect the delivered luminosity from the Tevatron to increase to ~10 fb-1 (analyzed) by the end of the run, an increase by a factor of ~2–3. Analysis improvements will add also sensitivity. These allow substantial improvements for: • Low massHiggs search • W mass • Diboson production • Top quark mass • Electroweak production of single top, Vtb • Heavy b-quark states and CP violation in BS • Resolving hints of new phenomena Difficult for LHC CDF & DØ are running smoothly and efficiently; no indications of detector problems. Collaboration strengths are sufficient to carry out the program. We are having fun but feel like the warmup act for the star performer. Good luck, and I hope you blow us out of the water before long.

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