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

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Presentation on theme: "CKM Fits: What the Data Say Stéphane T’Jampens LAPP (CNRS/IN2P3 & Université de Savoie) On behalf of the CKMfitter group"— Presentation transcript:

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

2 The CKM Matrix: Four Unknowns Measurement of Wolfenstein parameters: from |V ud | (nuclear transitions) and |V us | (semileptonic K decays)  combined precision: 0.5% from |V cb | (inclusive and exclusive semileptonic B decays)  combined precision: 2% from (mainly) CKM angle measurements:  combined precision: 20% (  ), 7% (  ) W –W – Q q V qQ Q  q

3 Inputs:  m s 17 <  m s < 21 ps C.L. hep-ex/ hep-ex/  m s : (stat.) ± 0.07 (syst.) ps

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

5 Inputs (major changes): sin 2  “The” raison d’être of the B factories: ICHEP ‘06 Conflict with sin2  eff from s-penguin modes ? (New Physics (NP)?) ± ± [BABAR(348m)] ± ± [Belle (532m)] sin2  = ± (0.023 stat-only) NB: a disagreement would falsify the SM. The interference NP/SM amplitudes introduces hadronic uncertainties  Cannot determine the NP parameters cleanly C(J/   ) = ± ± [BABAR] ± ± [Belle] ± (0.017 stat-only) 0.55 ± 0.11 ± 0.02 [BABAR(347m)] 0.64 ± 0.10 ± 0.02 [Belle (532m)] sin2  (  ’K 0 )= 0.60 ± ± 0.34 [BABAR(347m)] 0.44 ± 0.27 ± 0.05 [Belle (386m)] sin2  (  K 0 )= 0.31 ± 0.21 NP can contribute differently among the various s-penguin modes Meaning of the average?

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

7 Isospin Analysis: B→  B A B AR (347m) Belle (532m) Average S  –0.53 ± 0.14 ± 0.02–0.61 ± 0.10 ± 0.04–0.58 ± 0.09 C  –0.16 ± 0.11 ± 0.03–0.55 ± 0.08 ± 0.05–0.39 ± 0.07 “agreement”: 2.6σ BABAR & Belle

8 Isospin Analysis: B→  B A B AR (347m) Belle (275m) Average S  –0.19 ± ± 0.41 ± 0.09–0.13 ± 0.19 C  –0.07 ± 0.15 ± ± 0.3 ± 0.09–0.06 ± 0.14 BABAR & Belle  = [ 94 ± 21 ] º Isospin analysis : 0.86 ± 0.06 f L 00 B A B AR (347m) (1.2±0.4±0.3)x10 -6 BR

9 Isospin analysis B→  :Isospin analysis B→  : Isospin Analysis: angle  eff  B→  |  -  eff | < 22.4º (95% CL)|  -  eff | < 32.1º (95% CL)

10 Isospin Analysis: angle  B→  /  /  B→  : at very large statistics, systematics and model-dependence will become an issue B→ρ  Dalitz analysis: model-dependence is an issue !  B-Factories = [ 93 ] º  Global Fit = [ 98 ] º (include new  Dalitz BABAR)

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

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

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

14 Radiative Penguin Decays: BR(B→  )/BR(B→K*  ) Belle (386m) B A B AR (347m) 1.06 ± ± 0.07 ++ 00

15 Hypothesis: NP in loop processes only (negligible for tree processes) Mass difference:  m s = (  m s ) SM r s 2 Width difference:  s CP = (  s ) SM cos 2 (2  -2  s ) Semileptonic asymmetry: A s SL =-Re(  12 /M 12 ) SM sin(2  s )/r s 2 S  = sin(2  -2  s ) Grossman, PL B380, 99 (1996) Dunietz, Fleischer, Nierste, PRD 63, (2001) NP wrt to SM: reduces  s enhances  m s B s mixing phase very small in SM:  = (deg)  Bs mixing: very sensitive probe to NP UT of B d system: non-degenerated  (h d,  d ) strongly correlated to the determination of ( ,  ) UT of B s system: highly degenerated  (h s,  s ) almost independent of ( ,  ) NP Parameterization in B s system

16 0.2 fb -1  (  m s )= 0.035,  (sin(2  )=0.1  m s,  s and A s SL First constraint for NP in the B s sector Still plenty of room for NP Large theoretical uncertainties: LQCD h s ~<= 3 (h d ~<=0.3, h K ~<= 0.6) NP in B s System

17 Prospective: LHCb 2fb -1 (2010 ?)? assumptions:  (  m s )=0.01  (  ) = 10º  (  ) = 5º note: “expected” improvement from Lattice QCD is taken into account.  (sin2  )=0.02

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  from B→3 ,4 , etc., P EW, …] B s : 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 B s transitions can be harnessed as powerful probes for NP (  : “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/ Bayesian Statistics at Work: the Troublesome Extraction of the CKM Angle  (J. Charles, A. Höcker, H. Lacker F.R. Le Diberder and S. T’Jampens)

20 BACKUP SLIDES

21

22 G. Isidori – Beauty ‘03

23 Roger Barlow: YETI06Everything you wanted to know about limits Bayes at work = x P(0 events| ) (Likelihood) Prior: uniform Posterior P( )  3 P( ) d = Same as Frequentist limit - Happy coincidence Zero events seen P(n; )=e - n /n!

24 Roger Barlow: YETI06Everything you wanted to know about limits Bayes at work again = x P(0 events| ) Prior: uniform in ln Posterior P( )  3 P( ) d >> Is that uniform prior really credible? Upper limit totally different!

25 Roger Barlow: YETI06Everything you wanted to know about limits 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.


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