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CKM Fits: What the Data Say

CKM Fits: What the Data Say. Stéphane T’Jampens LAPP (CNRS/IN2P3 & Université de Savoie). On behalf of the CKMfitter group http://ckmfitter.in2p3.fr. Q  q. W –. Q. V qQ. q. from | V ud | (nuclear transitions) and | V us | (semileptonic K decays)  combined precision: 0.5%

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CKM Fits: What the Data Say

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  1. CKM Fits: What the Data Say Stéphane T’Jampens LAPP (CNRS/IN2P3 & Université de Savoie) On behalf of the CKMfitter group http://ckmfitter.in2p3.fr

  2. Q q W– Q VqQ q • from |Vud| (nuclear transitions) and |Vus| (semileptonic K decays)  combined precision: 0.5% • from |Vcb| (inclusive and exclusive semileptonic B decays)  combined precision: 2% • from (mainly) CKM angle measurements:  combined precision: 20% (), 7% ( ) The CKM Matrix: Four Unknowns Measurement of Wolfenstein parameters:

  3. +0.33 -0.18 Dms : 17.31 (stat.) ± 0.07 (syst.) ps-1 Inputs: Dms hep-ex/0603029 17 < Dms < 21 ps-1 @90 C.L. hep-ex/0606027

  4. Inputs (major changes): |Vub| (incl.) |Vub| (incl.) [10-3] = 4.48 ± 0.24 ± 0.39 (our average)

  5. Inputs (major changes): sin2 • “The” raison d’être of the B factories: 0.710 ± 0.034 ± 0.019 [BABAR(348m)] 0.642 ± 0.031 ± 0.017 [Belle (532m)] sin2b= 0.674 ± 0.026 (0.023 stat-only) 0.070 ± 0.028 ± 0.018 [BABAR] -0.018 ± 0.021 ± 0.014 [Belle] ICHEP ‘06 C(J/yK0) = 0.012 ± 0.022 (0.017 stat-only) • Conflict with sin2efffrom s-penguin • modes ? (New Physics (NP)?) 0.55 ± 0.11 ± 0.02 [BABAR(347m)] 0.64 ± 0.10 ± 0.02 [Belle (532m)] sin2b (h’K0)= 0.60 ± 0.08 0.12 ± 0.34 [BABAR(347m)] 0.44 ± 0.27 ± 0.05 [Belle (386m)] NB: a disagreement would falsify the SM. The interference NP/SM amplitudes introduces hadronic uncertainties  Cannot determine the NP parameters cleanly sin2b (fK0)= 0.31 ± 0.21 NP can contribute differently among the various s-penguin modes Meaning of the average?

  6. Penguin : competitive ? Tree : dominant Inputs (major changes): angle a • Time-dependent CP observable : realistic scenario Time-dependent CP analysis of B0  +–alonedetermineseff : but, we need  ! Isospin analysis ( can be resolved up to an 8-fold ambiguity within [0,])

  7. Isospin Analysis: B→ pp “agreement”: 2.6σ BABAR & Belle

  8. BABAR (347m) +0.11 -0.13 fL00 0.86 ± 0.06 BR00 (1.2±0.4±0.3)x10-6 a = [ 94 ± 21 ] º Isospin Analysis: B→ rr +0.05 -0.07 BABAR & Belle • Isospin analysis :

  9. |a-aeff| < 22.4º (95% CL) |a-aeff| < 32.1º (95% CL) Isospin Analysis: angle aeff [B→ pp/rr] • Isospin analysis B→pp: • Isospin analysis B→rr:

  10. +11 -9 aB-Factories = [ 93 ] º +5 -19 aGlobal Fit = [ 98 ] º Isospin Analysis: angle a [B→pp /rp /rr] (include new rp Dalitz BABAR) B→rr: at very large statistics, systematics and model-dependence will become an issue B→ρ Dalitz analysis: model-dependence is an issue !

  11. Inputs: Putting it all together t h e g l o b a l C K M f i t

  12. The global CKM fit: Testing the CKM Paradigm CP Conserving CP Violating CP-insensitive observables imply CP violation ! Angles (no theory) No angles (with theory)

  13. The global CKM fit: Testing the CKM Paradigm (cont.) ICHEP 2006 Tree (NP-Free) Loop [No NP in DI=3/2 b→d EW penguin amplitude Use a with b (charmonium) to cancel NP amplitude] CKM mechanism: dominant source of CP violation The global fit is not the whole story: several DF=1 rare decays are not yet measured  Sensitive to NP

  14. BABAR (347m) Belle (386m) r0g 0.77 ± 0.07 1.25 +0.21 -0.19 +0.37 +0.07 -0.33 -0.06 r+g 1.06 ± 0.09 0.55 +0.35 -0.31 +0.42 +0.09 -0.36 -0.08 Radiative Penguin Decays: BR(B→rg)/BR(B→K*g)

  15. NP Parameterization in Bs system Grossman, PL B380, 99 (1996) Dunietz, Fleischer, Nierste, PRD 63, 114015 (2001) Hypothesis: NP in loop processes only (negligible for tree processes) Mass difference: Dms = (Dms)SM rs2 Width difference: DGsCP = (DGs)SMcos2(2c-2qs) Semileptonic asymmetry: AsSL=-Re(G12/M12)SM sin(2qs)/rs2 Syf = sin(2c-2qs) • NP wrt to SM: • reduces DGs • enhances Dms UT of Bd system: non-degenerated  (hd,sd) strongly correlated to the determination of (r,h) UT of Bs system: highly degenerated  (hs,ss) almost independent of (r,h) Bs mixing phase very small in SM: c=1.05+0.06 (deg) Bs mixing: very sensitive probe to NP

  16. 0.2 fb-1 NP in Bs System s(Dms)= 0.035, s(sin(2c)=0.1 Dms, DGs and AsSL First constraint for NP in the Bs sector Still plenty of room for NP Large theoretical uncertainties: LQCD hs ~<= 3 (hd ~<=0.3, hK ~<= 0.6)

  17. s(Dms)=0.01 s(sin2b)=0.02 s(g) = 5º s(a) = 10º Prospective: LHCb 2fb-1 (2010 ?)? note: “expected” improvement from Lattice QCD is taken into account. assumptions:

  18. Conclusion • CKM mechanism: success in describing flavor dynamics of many constraints from vastly different scales. • With the increase of statistics, lots of assumptions will be needed to be reconsidered [e.g., extraction of a from B→3p,4p, etc., PEW, …] • Bs: an independent chapter in Nature’s book on fundamental dynamics • there is no reason why NP should have the same flavor structure as in the SM • Bs transitions can be harnessed as powerful probes for NP (c: “NP model killer”) • Before claiming NP discovery, be sure that everything is “under control” • (assumptions, theoretical uncertainties, etc.) • There are still plenty of measurements yet to be done

  19. Do Not Miss: hep-ph/0607246 Bayesian Statistics at Work: the Troublesome Extraction of the CKM Angle a (J. Charles, A. Höcker, H. Lacker F.R. Le Diberder and S. T’Jampens)

  20. BACKUP SLIDES

  21. G. Isidori – Beauty ‘03

  22. Bayes at work Zero events seen P(n; )=e-n/n! x =    Posterior P() P(0 events|) (Likelihood) Prior: uniform • 3P() d= 0.95 0 Same as Frequentist limit - Happy coincidence Everything you wanted to know about limits

  23. Bayes at work again Is that uniform prior really credible? x =    Prior: uniform in ln l P(0 events|) Posterior P() Upper limit totally different! • 3P() d >> 0.95 0 Everything you wanted to know about limits

  24. Bayes: the bad news • The prior affects the posterior. It is your choice. That makes the measurement subjective. This is BAD. (We’re physicists, dammit!) • A Uniform Prior does not get you out of this. Everything you wanted to know about limits

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