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A big success with more than 200 participants

A big success with more than 200 participants. AIM OF THE WORKSHOP. Make an overall status of our knowledge of the CKM parameters at the end of the era of CLEO, LEP, SLD, TeVatron I (reach consensus to start from common base). Try to define priorities for theoretical developments

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A big success with more than 200 participants

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  1. A big success with more than 200 participants

  2. AIM OF THE WORKSHOP Make an overall status of our knowledge of the CKM parameters at the end of the era of CLEO, LEP, SLD, TeVatron I (reach consensus to start from common base) Try to define priorities fortheoretical developments and future measurements : - in a short timescale (B-Factories/TeVatron II) - in a longer timescale (bridging today LHC)

  3. Structure of the Workshop Working Group I : Vub, Vcb and Lifetimes Working Group II : Vtd, Vts Working Group III : CKM Fits Lattice Data Group(LDG) Forum on Averaging (for PDG + users) Talks on : Charm and Kaon Physics

  4. B Oscillations b d, s d, s b Vtd,Vts In the Wolfenstein parameterization 4 parameters : l ,A, r, h The CKM Matrix d s b u b 1-l2/2 l A l3(r-ih) c,u Vub,Vcb c -l 1-l2/2 Al2 B decays t A l3(1-r-ih) -Al2 1 Vtb

  5. Measurements Measurements Theory UT parameters • Analysis Methods • Analysis Systematic To be continued at B-Factories and TeVatron • Theoretical assumptions • Theoretical uncertainties Possible measurements Error Meaning (discussion) Statistical Methods to extract UT parameters

  6. Vcb Vub Lifetimes WORKING GROUP I c,u b Vub,Vcb B decays

  7. n Inclusive Determination of Vcb l b c Vcb Vcb BR sl + t b Average by LEP Working Groups

  8. (l1 Fermi movement inside the hadron) m2p mb ( also named L) Determination of Vcb limited by theoretical uncertainties ….. The expression of Vcb in the low scale running HQ masses formalism (as an example)* Vcb = 0.0415  ( 1 - 0.012 m2p- 0.010 mb+ 0.006 as + 0.007 r Can these parameters be determined experimentally ? * In “Upsilon expansion” formalism : Vcb = 0.0419  ( 1 + 0.017 l1- 0.012mb 0.019 pert)

  9. From CLEO measurements

  10. Other experiments should perform this analysis …….

  11. Part of theoretical error on Vcb becomes experimental from the determination of m2pand mb Value agreed at the end of the Workshop Vcb(inclusive)= ( 40.7 ± 0.7 ± 0.8 ) 10-3 It was± 2.0 and of theo. origin !

  12. Exclusive Determination of Vcb G(w) contains kinematics factors and is known (also r1 and r2) F(w) is the form factor describing the B D* transition At zero recoil (w=1), as MQ F(1)  1 Strategy : Measure dG/dw and extrapolate to w=1 to extract F(1) Vcb

  13. F(1) |Vcb|2 Syst. dominated by the knowledge of the D** (for LEP) r2

  14. F(1) 3 determinations At the Workshop agreement onF(1) = 0.91±0.04 (Gauss.)

  15. What’s next to improve Vcb Experimental side: More and new moment analyses B-factories can perform both exclusive and inclusive analyses Form factors measurements in BD*ln Theory side : More work on the theory for the m2p ,mbextraction Unquenched F(1) calculations Studies of eventual correlation between inclusive and excluive determinations

  16. Combing the inclusive and the exclusive measurements : Vcb = (41.8 ± 1.0 ) 10-3

  17. Inclusive determination of Vub Vub Challenge measurement from LEP Using several discriminant variables to distinguish between the transitions : b  c b  u B  Xu l n

  18. Results from all the LEP experiments

  19. New determination At the Workshop we agreed on Vub(inclusive) = (4.09 ± 0.46 ± 0.36) 10-3

  20. Vub = (3.68 ± 0.55 +0.28(syst.))10-3(in ISGW2 Model) - 0.37 Exclusive determination of Vub B ®p(r) l n Babar Vub = (3.68 ± 0.14 +0.21(syst.)± 0.55(theo.))10-3 CLEO - 0.29 Important theoretical uncertainties from different models NOW, Lattice QCD calculations start to be precise

  21. What’s next to improve Vub Experimental side: B-factories can perform inclusive/end-point/exclusive analyses Correspondence between Dpln and B  pln Theory side : More work on the theory for the extraction of inclusive/end-point analyses Lattice QCD calculations for exclusive form factors Correlations between the different Vub determinations

  22. Lifetimes All lifetimes of weakly decaying B hadrons have been precisely measured Very important test of the B decay dynamics

  23. t(B+)/ t(B0) about 5s effect in agreement with theory t(B0s)/ t(B0) about 1s effect in agreement with theory Is there a problem for LB ? Averages from LEP/SLD/Tevatron (+ B-Factories) t(B0d) = 1.543 ± 0.015 ps ( 1.0%) t(B+) = 1.658 ± 0.014 ps ( 0.9%) t(B0s) = 1.464 ± 0.057 ps ( 3.9%) t(LB) = 1.208 ± 0.051 ps ( 4.2%) The hierarchy was correctly predicted !

  24. Theory News…..

  25. Next improvements : Experiment side: t(B+)/ t(B0) from B factories But more important t(B0s) and t( LB ) from TeVatron …. and B Bc, c Theory side: Improvements of the Lattice QCD calculations

  26. WORKING GROUP II B Oscillations b d, s d, s b Vtd,Vts Dmd Dms Radiative and Leptonic B decays Rare K decays

  27. Present Future

  28. Study of the time dependent behaviour of the Oscillation B0 -B0 TextBook Plot

  29. Dmd • LEP/SLD/CDF precisely measured the Dmd frequency • Dmd = 0.498 ± 0.013 ps-1 LEP/SLD/CDF (2.6 %) B-factories confirmed the value improving the precision by a factor 2 • Dmd = 0.496 ± 0.007 ps-1 LEP/SLD/CDF/B-factories (1.4%) Before B-Factories The final B-factories precision will be about 1% ( 0.004 ps-1 )

  30. At given Dms A = 0 no oscillation A = 1 oscillation Dms excluded at 95% CL A + 1.645sA < 1 Sensitivity same relation with A = 0 1.645sA < 1 Dms Combination of different limits using the amplitude methods Measurement of A at each Dms Combination using A and sA

  31. Dms [14.1-21.6] ps-1 at 95% CL “Hint of signal” at Dms=17.5 ps-1 but with significance at 1.7s Expectation in The Standard Model Dms > 14.9 ps-1 at 95% CL Sensitivity at 19.3 ps-1

  32. Very important achievement. The Dms information has to be included in the CKM Fits using the Likelihood Method. ( in the past this was a source of differences between the groups performing CKM fits)

  33. WORKING GROUP III Two subgroups : Vud,Vus the angle g Strategies CKM Fits

  34. B Oscillations b d, s d, s b Vtd,Vts In the Wolfenstein parameterization 4 parameters : l ,A, r, h The CKM Matrix d s b u b 1-l2/2 l A l3(r-ih) c,u Vub,Vcb c -l 1-l2/2 Al2 B decays t A l3(1-r-ih) -Al2 1 Vtb

  35. At 68% CL [0.68-1.06] [0.76-0.98] Treatment of the inputs Ex : BK = 0.87 ± 0.06 (gaus) ± 0.13 (theo.) Rfit Bayesian p.d.f. from convolution (sum in quadrature) Likelihood obtained summing linearly the two errors Likelihood Delta Likelihood Delta Likelihood

  36. Difference comes from how the inputs are treated : At present mainly from: F(1), inclusive Vcb, BK Breakdown of the error is important The splitting between Gaussian and theoretical error is crucial and somehow arbitrary Where the difference is coming from ? eK ( Vcb4* BK) Results of the Workshop : theoretical error reduced and origin of the error better defined

  37. Differences are small and physics conclusions quantitatively the same

  38. The difference ( which is by the way small ) on the CKM quantities coming from the different methods, is essentially due to the different treatment of the theoretical errors Using Likelihoods as obtained from linear sum of Exp.+Theo. errors Both methods use the same likelihood Using Likelihoods as obtained from convolution of Exp. Theo. errors Differences almost disappears

  39. Another example with sin2b (without eK )

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