Tevatron Physics Welcome new Fermilab director Nigel Lockyer Reinhard Schwienhorst Outline • Tevatron proton-antiproton collider • Heavy flavor production • QCD events • Electroweak results • Top quark measurements • Higgs boson coupling to fermions • Conclusions 2 Reinhard Schwienhorst Tevatron at Fermilab •Run II from 2002 to 2011 •CDF and D0: 400 + 400 members from 60 + 70 institutions 3 Reinhard Schwienhorst Tevatron collider in Run II • proton-antiproton collider • 1.96 TeV • 12 fb-1 delivered • 10 fb-1 recorded per experiment • 10 pByte dataset (incl. MC) per experiment 4 Reinhard Schwienhorst Unique Tevatron physics • proton-antiproton collider - quark-antiquark interactions - top pairs - forward-backward asymmetries - single top in the s-channel • lower CM energy - Higgs to bb in associated production - lower QCD background - coupling to fermions • Much less pileup than LHC - clean events, low trigger thresholds - precision top quark mass - precision W boson mass 5 Reinhard Schwienhorst Heavy flavor physics • Trigger and detector systems for heavy flavor - low-pT di-muons and regular reversal of B field (DØ) - track trigger and high-precision tracking (CDF) 6 Reinhard Schwienhorst CP Asymmetries • Tevatron Proton-Antiproton initial state - CP conserving • Look for neutral meson mixing • Look for asymmetries in heavy flavor decay rates • Sensitive to new physics - in weak and strong interactions 7 Reinhard Schwienhorst Like-sign di-muon asymmetry • DØ di-muon asymmetry in semi-leptonic B decays - Significance 3.9 s.d. PRD 84, 052007 (2011) • Measure asymmetry in semi-leptonic decays s 0 s • a sl in Bs → µD X PRL 110, 011801 (2013) d 0 (*)- • a sl in Bd → µ D X PRD 86, 072009 (2012) • Results consistent with zero and with di-muon asymmetry 8 Reinhard Schwienhorst CP Asymmetry for B± • Asymmetry A: Difference in decay rate for B+ and B- - CP violation in weak decay • Small (<0.3%) in SM • Result: - Consistent with zero • Most precise measurement PRL 110, 241801 (2013) 9 Reinhard Schwienhorst neutral D meson mixing (K −π + )π + Right-sign D*→ D0π + (K +π − )π + Wrong-sign Complete fit include B decays No mixing Pure charm CDF public note 10990 10 Reinhard Schwienhorst QCD physics • Strong interaction ⬌ ● Parton distribution functions studies (PDF) • Background to most Higgs, top, new physics analyses 11 Reinhard Schwienhorst QCD jet observables # of neighboring jets R (p , pnumber ) = ΔR T T min # of inclusive jets • Study strong interaction in jet formation • Minimal dependence on PDFs • Extend energy reach beyond Lep PLB 718, 56 (2012) Using RΔR and NLO+MSTW2008NNLO PDFs 12 Reinhard Schwienhorst Photon + heavy flavor CDF note 10818 • Sensitive to b-quark and charm quark PDF 13 Reinhard Schwienhorst Electroweak results 14 Reinhard Schwienhorst ZZ cross section • llll and llνν final states • Background to Higgs and new physics searches CDF public note 10957 accepted by PRD, arXiv:1304.5422 15 Reinhard Schwienhorst Electroweak measurements • All single and di-boson processes measured • Also look for anomalous boson couplings in di-bosons 16 Reinhard Schwienhorst W boson mass • Well understood detectors • Well understood theory errors • Clean event environment • Expect final Tevatron measurement with <10 MeV uncertainty 17 Reinhard Schwienhorst sinθW from Z→ee • Measured A4 (V-A interference) from cosθ term of the angular distribution of e+e− pairs with 2 Mee in [66,116] GeV/c lep • Derived sinθeff and MW from A4 and ResBos prediction PRL 106, 241801 (2011) arXiv:1307.0770, PRD CDF public note 10952 18 Reinhard Schwienhorst Top quark 19 Reinhard Schwienhorst Top forward-backward asymmetry antiproton direction | proton direction Lepton charge × lepton η • SM prediction at NLO (QCD+EWK): Afb = (6.6 ± 2.0)% • Combined DØ result: l Afb = (11.8 ± 3.2)% → 2.2 s.d. above SM PRD 87, 011103 (2013) top quark rapidity 20 Reinhard Schwienhorst Differential top cross section lep • CDF: Afb = (9.4 ± 4.3)% lep • SM@NLO: Afb = 3.6% • Legendre moment to characterize shape • Supports s-channel type model - Favors s-channel axi-gluon - Disfavors t-channel Z’ CDF public notes 10974, 10975, submitted to PRL, arXiv:1306.2357 21 Reinhard Schwienhorst Single top quark production 1 DØ 9.7 fb -1 expected 0.8 +0.47 = 2.33 -0.44 pb 0.6 observed DØ 9.7 fb-1 +0.53 5 0.4 = 3.07 -0.49 pb 1 SD 2 SD 0.2 4 3 SD Posterior density 0 012345678 Measurement 3 [1] SM tqb cross section [pb] [2] Four generations [3] Top-flavor -1 [3] 16 DØ, 9.7 fb 2 Top pion [4] 14 FCNC |V |2 = 1.00 +0.00 12 tb -0.07 t-channel cross section [pb] [1] PRD 74: 114012, 2006 +0.00 1 [2] EPJ C49: 791, 2007 10 |V | = 1.00 [3] PRD 63: 014018, 2001 tb -0.04 [4] PRL 99: 191802, 2007 8 |V | > 0.92 @ 95% C.L. tb 0 6 012345 s-channel cross section [pb] 4 Posterior density 2 • CDF result and Tevatron 0 combination this summer 0 0.2 0.4 0.6 0.8 1 |V |2 • World’s best |Vtb| measurement tb 22 Reinhard Schwienhorst s-channel signal 2 DØ, 9.7 fb -1 ± 1 SD ± 2 SD 1 tb tqb (Data-Bkg)/Bkg [%] 0 -1 0.7 0.8 0.9 30 DØ, 9.7 fb Binned BNNComb discriminant s-channel Single Top Quark Cross Section 20 e/ +jets 3.2 fb-1 µ +0.70 CDF -1 1.80 pb MET+jets 2.1 fb -0.50 10 -1 +0.38 DØ e/µ+jets 5.4 fb 0.68-0.35 pb Yield [Events/0.04] -1 +0.63 CDF e/µ+jets 7.5 fb 1.81-0.58 pb 0 0.7 0.8 0.9 -1 +0.33 DØ e/µ+jets 9.7 fb 1.10 pb Binned BNNComb discriminant -0.31 N. Kidonakis m = 172.5 GeV PRD 74 114012 (2006) t 3.7 s.d. significance • -4 -2 0 2 4 • very difficult at LHC (pp tb+X) [pb] 23 Reinhard Schwienhorst Single top without leptons CDF public note 10979 • Same technique as Zh→ννbb • Select τ decays - And events lepton analysis missed 24 Reinhard Schwienhorst • Top mass reconstructed from top pair decay products • lepton+jets, di-lepton and all-jet final states 173.20 ± 0.87 GeV • Dominant uncertainties - Signal modeling - Jet energy scale 25 Reinhard Schwienhorst Top and W and Higgs boson masses top quark Higgs W boson boson 26 Reinhard Schwienhorst Vacuum stability • Extrapolate Higgs coupling to Planck Scale (1019 GeV) • Depends on top mass - Current value → Higgs quartic coupling negative at 1010 GeV 27 Reinhard Schwienhorst 28 Reinhard Schwienhorst Vacuum stability • Extrapolate Higgs coupling to Planck Scale (1019 GeV) • Depends on top mass - Current value → Higgs quartic coupling negative at 1010 GeV • Indication of new physics! 29 Reinhard Schwienhorst Higgs at the Tevatron • Measure Higgs coupling to Fermions - So far only place in the world to do so 30 Reinhard Schwienhorst Higgs: fermion coupling in associated production 31 Reinhard Schwienhorst final Tevatron Higgs combination Tevatron Run II, L 10 fb-1 10 int 2 Observed mH = 125 GeV/c Tevatron Run II, L 10 fb-1 Expected w/o Higgs int Combined (68% C.L.) SM Higgs combination Expected ±1 s.d. Single channel Expected ±2 s.d. 2 Expected if mH=125 GeV/c H - H W+W + - 95% C.L. Limit/SM H VH Vbb 1 SM=1 0 1 2 3 4 5 6 7 8 9 10 Best Fit ( × Br)/SM f Tevatron Run II, L 10 fb-1 6 int Local maxima SM 68% C.L. 95% C.L. 100 120 140 160 180 200 4 2 WZ=1 mH (GeV/c ) • Observed significance 3.0 s.d. 2 2 at mH = 125 GeV/c 0 • Coupling measurements consistent -2 with SM -4 0 0.5 1 1.5 2 Reinhard Schwienhorst 32 V Testing Higgs boson spin/parity • Spin/parity of Higgs affects - Angles of decay products - cross-section behavior at threshold ‣s-wave for 0+: σ∼β (SM) ‣p-wave for 0-: σ∼β3 ‣d-wave for 2+:σ∼β5 • pp → VH sensitive “threshold” effects • Differential cross sections depend strongly on JPC of new particle • Re-use published VH → Vbb analyses • results later this summer 33 Reinhard Schwienhorst Conclusions/Outlook • Tevatron physics impact - Top quark discovery, top and W boson mass measurements - First measurement of many cross sections and resonances - Higgs coupling to fermions - Limits on numerous new physics particles and interactions - Established hadron collider methods and analysis techniques • Tevatron data analysis still providing important results - Expect ~100 more papers • Unique collider provided precious dataset - CP symmetric collider at the highest energies - Well understood detectors - Higgs spin/parity tests - Follow up on anomalies • Tevatron legacy measurements - Cross section measurements - Precision measurements of mW and mtop - CP asymmetries 34 Reinhard Schwienhorst Thanks! • DØ and CDF collaborations • Physics coordinators - Bob Hirosky, Rick van Kooten, Jon Wilson, • Previous Tevatron speakers - Costas Vellidis, Andreas Jung, Bob Hirosky • Fermilab Result of the week - Tevatron physics for the informed public • CDF physics results: http://www-cdf.fnal.gov/physics/physics.html • DØ physics results: http://www-d0.fnal.gov/Run2Physics/WWW/results.htm 35 Reinhard Schwienhorst.