Latest results on top production from the CMS and ATLAS collaborations: inclusive and differential measurements

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1 Latest results on top production from the CMS and ALAS collaborations: inclusive and differential measurements E. assi On behalf of the CMS and ALAS Collaborations XLV International Symposium on Multiparticle Dynamics Wildbad Kreuth 4-9 October 5

2 Outline op quark pair production cross sections at the LHC (7, 8 and 3 ev) - otal inclusive - Differential (resolved and boosted regimes) Associated production of top quarks with a gauge boson - - t t+w, t -t + Z Single top production - t-channel - Wt channel - s-channel

3 Introduction years after its discovery top quark remains an intriguing particle he most massive elementary particle Decays before hadronising Could play a role in EWSB With its large top production rates, LHC is a top factory. his makes it possible to carry out a very important op Physics programme: Production and decay processes: test pqcd and EW Probe couplings to H and Z Significant background to Higgs and New Physics searches 3

4 op pair decays he leptonic/hadronic decays of the W fully characterise the final state signature 4

5 - production - pqcd arxiv: est of pqcd he total cross section for top pair production process is known with very high theoretical precision (NNLO +NNLL) Leading order terms: σ tot [pb] LO NLO LL Scale variation NNLO NLL NNLL LL NLL NNLL Fixed Order NLO+res NNLO+res 4 LHC 8 ev; m top =73.3 GeV; A= MSW8 LO; NLO; NNLO Gluon-initiated: 9% Quark initiated: % (@4 ev) PRL,54 (3) 5

6 - production - pqcd arxiv: est of pqcd he total cross section for top pair production process is known with very high theoretical precision (NNLO +NNLL) Leading order terms: σ tot [pb] LO NLO LL Scale variation NNLO NLL NNLL LL NLL NNLL Fixed Order NLO+res NNLO+res 4 LHC 8 ev; m top =73.3 GeV; A= MSW8 LO; NLO; NNLO Gluon-initiated: 9% Quark initiated: % (@4 ev) arxiv:56.64 Gluon density typical x-bjorken values of the initial partons: 6

7 otal inclusive cross sections for top pair production topwg ALAS+CMS Preliminary LHC σ summary, s = 7 ev Sep 5 NNLO+NNLL PRL (3) 54, PDF4LHC m top = 7.5 GeV scale ev uncertainty scale PDF α S total stat σ ±(stat) ±(syst) ±(lumi) ALAS, l+jets 79 ± 4 ± 9 ± 7 pb L int =.7 fb ALAS, dilepton (*) 73 ± 6 pb L int =.7 fb ALAS, all jets (*) 67 ± 8 ± 78 ± 6 pb L int =. fb ALAS combined 77 ± 3 ± 7 pb L int =.7. fb CMS, l+jets (*) 64 ± 3 ± ± 7 pb L int =.8. fb CMS, dilepton (*) 7 ± 4 ± 6 ± 8 pb L int =. fb CMS, τ had +µ (*) 49 ± 4 ± 6 ± 9 pb L int =. fb CMS, all jets (*) 36 ± ± 4 ± 8 pb L int =. fb CMS combined 66 ± ± ± 8 pb L int =.8. fb LHC combined (Sep ) 73 ± ± 8 ± 6 pb L int =.7. fb ALAS, l+jets, b Xµ ν 65 ± ± 7 ± 3 pb L int =4.7 fb ALAS, dilepton eµ, b-tag 8.9 ± 3. ± 4. ± 3.6 pb L int =4.6 fb miss ALAS, dilepton eµ, N -E jets 8. ±.8 ± 3.3 pb L int =4.6 fb ALAS, τ had +jets 94 ± 8 ± 46 pb L int =.7 fb ALAS, all jets 68 ± ± 7 pb L int =4.7 fb ALAS, τ had +l 83 ± 9 ± 3 ± 3 pb L int =4.6 fb he ALAS and CMS collaborations have measured the total inclusive cross sections for top pair production at 7, 8 and 3 ev All channels (di-lepton, l+jet and full had) have been exploited using diverse experimental approaches. able presents a summary of the results at: - 7 ev Run (based on ~ -5 fb ) CMS, l+jets 58 ± ± ± 4 pb L int =.-.3 fb CMS, dilepton eµ 74.5 ±. ± 3.8 pb L int =5. fb CMS, τ had +l 43 ± 4 ± ± 3 pb L int =. fb CMS, τ had +jets 5 ± ± 3 ± 3 pb L int =3.9 fb CMS, all jets 39 ± ± 6 ± 3 pb L int =3.5 fb (*) Superseded by results shown below the line Effect of LHC beam energy uncertainty: 3.3 pb (not included in the figure) [pb] σ 7

8 otal inclusive cross sections for top pair ev top WG ALAS+CMS Preliminary LHC σ summary, s = 8 ev Sep 5 NNLO+NNLL PRL (3) 54, PDF4LHC m top = 7.5 GeV scale uncertainty scale PDF α S uncertainty total stat σ ±(stat) ±(syst) ±(lumi) he ALAS and CMS collaborations have measured the total inclusive cross sections for top pair production at 7, 8 and 3 ev ALAS, lepton+jets PRD 9 (5) 3, CMS prel., lepton+jets CMS-PAS OP-6, CMS, lepton+τ h PLB 739 (4) 3, ALAS, dilepton eµ EPJ C74 (4) 39, L int =.3 fb L int =.8 fb L int =9.6 fb L int =.3 fb CMS, dilepton (ee, µµ, eµ) JHEP (4) 4, L int =5.3 fb LHC combined eµ (Sep 4) ALAS-CONF-4-53, CMS-PAS OP4-6, L int = fb 6 ± + 3 ± 8 pb ± 9 ± pb 6 57 ± 3 ± 4 ± 7 pb 4.4 ±.7 ± 5.5 ± 7.5 pb 39. ±. ±.3 ± 6. pb 4.5 ±.4 ± 5.7 ± 6. pb All channels (di-lepton, l+jet and full had) have been exploited using diverse experimental approaches. able presents a summary of the results (*) at: - 7 ev Run (based on ~ -5 fb ) - 8 ev Run (based on ~ fb ) CMS prel., dilepton eµ CMS-PAS OP3-4, CMS, all jets CMS OP4-8, L int =9.7 fb ±.3 ± 6.5 pb 5.5 L int =8.4 fb 75.6 ± 6. ± 37.8 ± 7. pb (*) For additional precise CMS results presently not included in the tables see also CMS OP3-4 Effect of LHC beam energy uncertainty: 4. pb (not included in the figure) σ [pb] 8

9 otal inclusive cross sections for top pair ev top WG ALAS+CMS Preliminary LHC σ summary, s = 3 ev Sep 5 NNLO+NNLL PRL (3) 54, PDF4LHC m top = 7.5 GeV scale uncertainty scale PDF α S uncertainty total stat σ ±(stat) ±(syst) ±(lumi) he ALAS and CMS collaborations have measured the total inclusive cross sections for top pair production at 7, 8 and 3 ev ALAS, dilepton eµ * ALAS-CONF-5-49 ALAS, dilepton ee/µµ * ALAS-CONF-5-49 ALAS, l+jets * ALAS-CONF-5-49 CMS, dilepton eµ * CMS-PAS OP5-3 CMS, l+jets * CMS-PAS OP5-5 * Preliminary L int =78 pb L int =85 pb L int =85 pb L int =4 pb L int =4 pb σ [pb] 89 ± 5 ± 56 ± 83 pb 749 ± 57 ± 79 ± 74 pb 87 ± 3 ± 3 ± 88 pb 77 ± 6 ± 6 ± 93 pb 836 ± 7 ± 84 ± pb All channels (di-lepton, l+jet and full had) have been exploited using diverse experimental approaches. able presents a summary of the results at: - 7 ev Run (based on ~ -5 fb ) - 8 ev Run (based on ~ fb ) 3 ev Run (based on 4-8 pb ) Best precision achieved so far on : 9-3.5% at 7 and 8 ev - 3.5% at 3 ev

10 Candidate top-pair event at 3 ev

11 Candidate top-pair event at 3 ev

12 otal inclusive cross sections for top pair 3 ev Events ALAS ALAS-CONF pb ALAS Preliminary s = 3 ev, 78 pb 5 Powheg+PY Wt Z+jets Diboson Mis-ID lepton Number of Events CMS CMS PAS OP5-3 4 pb 4 pb (3 ev) 5 4 CMS Preliminary e ± µ + jets Non W/Z VV tw 3 ± Z/γ* e µ ± ± /MC M e ± µ ± (GeV) N b-tag - Di-lepton channel (eμ) (gives slightly more precise results w.r.t the lepton+jet channel). - Very good description of the 3 ev data by MC generators.

13 otal inclusive cross sections for top pair 3 ev Events ALAS ALAS-CONF pb ALAS Preliminary s = 3 ev, 78 pb 5 Powheg+PY Wt Z+jets Diboson Mis-ID lepton Number of Events CMS CMS PAS OP5-3 4 pb 4 pb (3 ev) 5 4 CMS Preliminary e ± µ + jets Non W/Z VV tw 3 ± Z/γ* e µ ± ± /MC M e ± µ ± (GeV) N b-tag ALAS: CMS: 3

14 otal inclusive cross sections for top pair production cross section [pb] Inclusive 3 evatron combined*.96 ev (L=8.8 fb ALAS eµ 7 ev (L=4.6 fb ) CMS eµ* 7 ev (L=5 fb ) ALAS eµ 8 ev (L=.3 fb ) CMS eµ* 8 ev (L=9.7 fb ) LHC combined eµ* 8 ev (L= fb ALAS eµ* 3 ev (L=78 pb ) CMS eµ* 3 ev (L=4 pb ) ALAS ee/ µµ* 3 ev (L=85 pb ) ALAS l+jets* 3 ev (L=85 pb ) CMS l+jets* 3 ev (L=4 pb ) * Preliminary ) ) NNLO+NNLL (pp) s [ev] 4 ALAS+CMS Preliminary Sep 5 LHCtopWG NNLO+NNLL (pp) Czakon, Fiedler, Mitov, PRL (3) 54 = 7.5 GeV, PDF α uncertainties according to PDF4LHC m top S s [ev] Measurements, as a function of s, in excellent agreement with NNLO+NNLL pqcd predictions

15 op pair differential cross sections he measurement of single differential top pair cross sections allows one: - to perform particularly stringent test of pqcd - to improve on the determination of the gluon density - to test MC programs Will present new results at 8 and 3 ev (resolved and boosted regimes) Resolved regime: - well separated jets - isolated leptons Boosted regime: - overlapping decay products - non isolated leptons 5

16 op pair differential cross ev / GeV t / d p d σ /σ Prediction OPQ-5-6 ALAS Preliminary s = 8 ev,.3 fb lepton +jet Full phase-space PWG+PY6 h damp =m t PWG+PY8 h damp =m t MC@NLO+HW AUE MadGraph+PY6 PC PWG+HW6 AUE Stat. unc. Stat.+Syst. unc [GeV] t p GeV t dσ dp σ heory e/µ + Jets CMS, 9.7 fb MadGraph+Pythia6 MC@NLO+Herwig6 Powheg+Pythia6 Powheg+Herwig6 Approx. NNLO 5Stat Stat. Syst. at s t p = 8 ev (Phys.Part.Nucl. 45 (4) 74) t p GeV Full phase-space normalised parton-level cross sections (same binning for CMS and ALAS). - MC predictions, at high top p, show a harder spectrum than the data (Madgraph gives the worse description for both ALAS and CMS). 6 arxiv: GeV

17 op pair differential cross ev / Unit y / d y d σ /σ Prediction OPQ-5-6 ALAS Preliminary s = 8 ev,.3 fb lepton +jet Full phase-space PWG+PY6 h damp =m t PWG+PY8 h damp =m t MC@NLO+HW AUE MadGraph+PY6 PC PWG+HW6 AUE Stat. unc. Stat.+Syst. unc y dσ dy σ heory e/µ + Jets CMS, 9.7 fb MadGraph+Pythia6 MC@NLO+Herwig6 Powheg+Pythia6 Powheg+Herwig6 = 8 ev -.5 -Stat Stat. Syst...9 arxiv: at s y y - Full phase-space normalised parton-level cross sections (same binning for CMS and ALAS). - /MC comparison show similar trends for both ALAS and CMS. 7

18 op pair differential cross ev / Unit y / d y d σ /σ OPQ ALAS Preliminary s = 8 ev,.3 fb lepton +jet Fiducial phase-space Cnlo C4nlo CJmid MMH4nlo68cl NNPDF 3. NLO HERA. NLO MEAvLHC Stat. unc. Stat.+Syst. unc. dσ dm σ di-lepton Dilepton CMS, 9.7 fb arxiv: at s = 8 ev MadGraph+Pythia6 MC@NLO+Herwig6 Powheg+Pythia6 Powheg+Herwig6 NLO+NNLL (JHEP 9 (3) 3).4-5 Prediction y heory.5 4 Stat Stat. Syst. m m ALAS: visible (particle level) normalised differential cross sections are measured and compared to predictions based on recent PDF sets. reduced extrapolation uncertainties CMS: also measures fiducial normalised cross sections. Results are presented in addition in the di-lepton channel. 8

19 op pair differential cross ev CMS PAS-OP5-5 ] [GeV ) h dσ dp (t σ theory data pb (3 ev) CMS Preliminary l+jets data sys stat stat Powheg Pythia8 Powheg Herwig++ amc@nlo Madgraph p (t ) [GeV] h ) dσ dy(t σ h theory data CMS Preliminary 4 pb (3 ev) l+jets data sys stat stat Powheg Pythia8 Powheg Herwig++ amc@nlo Madgraph y(t ) h - First measurements of the normalised differential cross sections at 3 ev - All MC give a fair description of the measurements - otal cross section at 3 ev: in good agreement with NNLO predictions. 9

20 op pair differential cross sections 8 ev boosted regime OPQ-45 Particle Level CMS PAS-OP4- [fb/gev] t /dp dσ ALAS Preliminary Fiducial phase-space POWHEG+PYHIA ALPGEN+HERWIG MC@NLO+HERWIG POWHEG+HERWIG (/GeV) /σ dσ/dp - -3 CMS Preliminary 9.7 fb (8 ev) Powheg+Pythia6 MadGraph+Pythia6 Stat. Uncertainty Stat. Syst. - s = 8 ev,.3 fb -4 Pred. / Particle top-jet candidate p [GeV] heory/ Particle-level top p (GeV) As for the results in the resolved regime, the MC predictions, at high-p show a harder spectrum than the data. Both at particle

21 op pair differential cross sections 8 ev boosted regime [fb/gev] t /dp dσ OPQ-45 Full phase-space POWHEG+PYHIA ALPGEN+HERWIG MC@NLO+HERWIG POWHEG+HERWIG Parton Level (/GeV) /σ dσ/dp - -3 CMS PAS-OP4-9.7 fb CMS Preliminary (8 ev) Powheg+Pythia6 MadGraph+Pythia6 Stat. Uncertainty Stat. Syst. ALAS Preliminary s = 8 ev,.3 fb -4 Pred. / top quark p [GeV] heory/ op quark p (GeV) As for the results in the resolved regime, the MC predictions, at high-p show a harder spectrum than the data. Both at particle and parton level.

22 - production in association with W or 8 ev Dominant production modes: - - W and Z small expected cross sections ( ~ 8eV) - Z production cross section provide most accessible direct measurement to the coupling of the top quark to the Z - - Both σ(w) and σ(z) expected to be altered in new physics models

23 W, Z cross 8 ev CMS PAS-OP4-5 mutually exclusive signal channels - at least lepton with p > GeV - p > GeV for additional leptons Even after selection final signal categories are background dominated Events 3 eµ + 4 jets + b tags Nonprompt Ch. misid WZ Other H Post-fit yields Z 9.5 fb (8 ev) W CMS (b) Use full reconstruction and linear discriminant to - match system Match scores and other rec. variables into a Boosted Decision ree (BD) Cross sections extracted from binned likelihood fit /Pred. -5 Match score W lν blν bqq 3

24 W, Z cross 8 ev CMS PAS-OP4- Events 5 µ µ + 4 jets + b-tags 9.5 fb (8 ev) Non-prompt WZ Other H Z W Post-fit CMS Preliminary 5 5 /Pred. Events W BD µ µ + 3 jets + b-tags 9.5 fb (8 ev) 3 Non-prompt WZ Other H Z W Post-fit CMS Preliminary Cross section measurements: /Pred W BD Source of slight excess in W, consistent with CMS excess in H 4

25 W, Z cross 8 ev Final results 5 signal regions and 5 control regions - at least lepton with p > GeV - p> 5 or 7 GeV for additional leptons OS leptons: NN used to separate W and Z from the background Events / bin ALAS, arxiv: ALAS s = 8 ev,.3 fb L-noZ-5j W op Rare SM V norm Z Z otal unc. Events 5 5 ALAS s = 8 ev,.3 fb eµ-ss W Z Charge misid Fake leptons Rare SM otal unc. / SM NN output 5 All signal and control regions are combined in a profile likelihood fit with σ(z) and σ(w) as free parameters. Low-E [,3] n jets miss Low-E 4 n jets miss High-E n jets miss [,3] High-E n jets 4 miss 5

26 W, Z cross 8 ev Post fit results (per region): ALAS, arxiv: Events / channel ALAS 6 CR LOS s = 8 ev,.3 fb op VV Rare SM Z otal unc. Charge misid Fake leptons Z W 5 LSS 4 3 3L L noz -b 3j b Z 3j b Z ZZ b Z 4j 3j noz -b 4j noz -b 5j+ b Z 5j+ ee b+ eµ b+ µµ b+ b Z 4j+ Z b+ 3j Z b+ 4j+ noz b+ -3j DF b DF b DF b+ SF b SF b+ Measured cross sections: Z cross section [fb] 6 ALAS ALAS Best Fit s = 8 ev,.3 fb ALAS 68% CL ALAS 95% CL NLO prediction* Z heory uncertainty W heory uncertainty he observed (expected) significance of: - W is 5.σ (3.σ) - Z is 4.σ (4.5σ) 6 * Madgraph5_aMC@NLO calculation W cross section [fb]

27 Single top production One forward jet One lepton One b-jet Missing transverse energy t-channel wo oppositely charged leptons One high-p and central b-jet Missing transverse energy Wt-channel One isolated and high-p lepton wo b-jets with high-p Missing transverse energy s-channel 7

28 t-channel single 8 ev CMS PAS OP4-4 One electron (muon) with p > 3 GeV (6 GeV) jet p > 4 GeV Emiss > 45 GeV, m(w) > 5 GeV Measure differential cross sections CMS PAS OP5-7 Fiducial cross section measurement recently released CMS PAS OP5-7 CMS Preliminary 3.38 ±.5 (exp.) ±. (theo.) pb amc@nlo, 4FS (scale pdf) POWHEG, 4FS (scale pdf) POWHEG, 5FS (scale pdf) 9.7 fb (8 ev) dσ/dp /σ.5.4 CMS Preliminary 9.7 fb (8 ev) POWHEG (5FS) + Pythia6 amc@nlo (4FS) + Pythia8 CompHEP + Pythia6 dσ/d y /σ CMS Preliminary 9.7 fb (8 ev).35 POWHEG (5FS) + Pythia6.3 amc@nlo (4FS) + Pythia8 CompHEP + Pythia fid. [pb] σ t -ch Simulation top p [GeV] Simulation top y CMS PAS OP4-4

29 t-channel single 3 ev CMS PAS-OP5-4 Events / jet -tag (SR) CMS Preliminary 4 pb t -channel, tw W/Z+jets QCD (3 ev) Events / jet -tag CMS Preliminary 4 pb t -channel, tw W/Z+jets (3 ev) 6 4 / MC η j' / MC η j' Measured cross section: Observed (expected) significance: 3.5σ(.7σ) heory: 9

30 OPQ-- tw single 8 ev Di-lepton selection with or jets (, or b-tag) BD to separate signal from Wt inclusive cross section: Events 4 ALAS Preliminary s = 8 ev,.3 fb Wt or jets 8 Others Uncertainty - Wt + fiducial cross section measured by fiing - the sum of the Wt and contributions to data in the -jet -tag region: /Pred jet -tag -jet -tag -jet -tag -jet -tag -jet -tag Regions ALAS Preliminary s = 8 ev,.3 fb Measured fiducial Wt+ cross-section otal uncertainty Stat. uncertainty Predicted fiducial cross-sections: DR C POWHEG-BOX+PYHIA σ Wt at NLO+NNLL, σ at NNLO+NNLL POWHEG-BOX+PYHIA σ Wt and σ at NLO POWHEG-BOX+PYHIA σ Wt and σ at NLO DR C DS C POWHEG-BOX+HERWIG DR C σ Wt and σ at NLO MC@NLO+HERWIG DR C σ Wt and σ at NLO MC@NLO+HERWIG DR MSW8 σ Wt and σ at NLO MC@NLO+HERWIG DR NNPDF.3 σ Wt and σ at NLO Cross-section [pb] 3 Events /.5 /Pred ALAS Preliminary s = 8 ev,.3 fb -jet -tag Post-fit Wt Others Uncertainty BD Response

31 s-channel single top ALAS-CONF-5-47 Selection: One lepton + b-jets and Emiss Discriminant: - Build Matrix Element discriminant for each selected event - - s-channel vs t-channel,, W+jets - emplate fit in signal and control region Cross section: Observed (expected) significance: 3.σ (3.9σ) First evidence of the s-channel production at LHC 3

32 Summary of Single top measurements otal inclusive cross-section [pb] LHCtopWG ALAS+CMS Preliminary Single top-quark production Sep 5 t-channel ALAS t-channel PRD9(4) 6, ALAS-CONF-4-7 CMS t-channel JHEP() 35, JHEP6(4) 9 ALAS Wt PLB76 () 4, paper in preparation CMS Wt PRL (3) 3, PRL(4) 38 LHC combination, Wt ALAS-CONF-4-5, CMS-PAS-OP4-9 ALAS s-channel ALAS-CONF-8 95% C. L., ALAS-CONF-5-47 CMS s-channel, 95% C.L. CMS-PAS-OP3-9 NNLO PLB736 (4) 58 m top = 7.5 GeV, MSW8nnlo scale uncertainty NLO + NNLL PRD83() 953, PRD8() 548, PRD8() 548 m top = 7.5 GeV, MSW8nnlo Wt: contribution removed scale PDF α s uncertainty, t -channel total cross section [pb] CMS Preliminary NLO+NNLL QCD ± (scale PDF) Kidonakis, Phys. Rev. D 83 () 953 evatron.96 ev (L 9.7 fb ) arxiv:53.57 CMS 7 ev (L =.7/.56 fb ) JHEP () 35 CMS 8 ev (L = 9.7 fb ) JHEP 6 (4) 9 CMS 3 ev (L = 4 pb ) CMS-OP5-4, preliminary s [ev] Wt s-channel NLO NPPS5(), CPC9(5) 74 m top = 7.5 GeV, µ = µ = m top, R F Cnlo, MSW8nlo, NNPDF.3nlo (PDF4LHC) b Wt: p veto for removal= 6 GeV and µ =65 GeV F scale uncertainty uncertainty scale PDF α s All exp. results are w.r.t. m = 7.5 GeV top syst stat s [ev] All the measurements are so far consistent with the SM predictions 3

33 Summary of V tb determinations at 7 and 8 ev ALAS+CMS Preliminary f LV V tb = σ σ meas. theo. LHCtopWG from single top quark production σ theo : NLO+NNLL MSW8nnlo PRD83 () 953, PRD8 () 548, PRD8 () 548 σ theo : scale PDF m top = 7.5 GeV t-channel: ALAS 7 ev PRD 9 (4) 6 (4.59 fb ) ALAS 8 ev ALAS-CONF-4-7 (.3 fb ) CMS 7 ev JHEP () 35 ( fb CMS 8 ev JHEP 6 (4) 9 (9.7 fb ) CMS combined 7+8 ev JHEP 6 (4) 9 Wt: ALAS 7 ev PLB 76 () 459 (.5 fb CMS 7 ev PRL (3) 3 (4.9 fb ALAS 8 ev (*) ALAS-CONF-3 (.3 fb CMS 8 ev PRL (4) 38 (. fb, LHC combined 8 ev ALAS-CONF-4-5, CMS-PAS-OP4-9 Wt:, ALAS 8 ev paper in preparation (.3 fb ) ) s-channel: ALAS 8 ev ALAS-CONF-5-47 (.3 fb ) ) ) ) ) (*) Superseeded by results shown below the line total theo. f LV V tb ± (meas.) ± (theo.). ±.6 ±..97 ±.9 ±.. ±.46 ± ±.45 ± ±.38 ± ± ±. ±.3.3 ±. ±.4.6 ±. ±.3. ±. ± ±.4.3 Sep 5 including top-quark mass uncertainty including beam energy uncertainty Direct determination of the matrix element Vtb : est the unitary of the CKM Matrix Sensitivity to new physics Measure Vtb assuming left-handed SM-like W-t-b coupling (and Vtb >> Vts, Vtd ): with in the SM f LV V tb 33

34 Summary op quark pair production cross sections at the LHC (7, 8 and 3 ev) - inclusive cross sections: - new 8 and 3 ev results from ALAS and CMS - excellent agreement with pqcd (NNLO+NNLL) - Differential cross sections: - new 8 ev (resolved and boosted regimes) and 3 ev results - 8 ev measurements have discriminating power (MC generators, PDFs) Associated production of top quarks with a gauge boson Z and W: improved cross sections measurements Single top production - t-channel: - new 3 ev result from CMS - Wt channel: - Wt cross sections has been measured with a precision of 3% in CMS and 7% in ALAS - First Wt + t -t fiducial cross section measurement by ALAS - s-channel: - First evidence of the s-channel by ALAS a rich op Physics Programme ahead of us with the ongoing Run 34