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hoecker@lal2p3.fr

B Physics , CP Violation and the CKM Fit. Andreas Höcker (LAL, Orsay). FNAL Colloquium, May 18, 2005. hoecker@lal.in2p3.fr. Outline. Themes :. Introduction CKM phase invariance and unitarity Statistical issues CKM metrology the traditional inputs deep B physics : , , 

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hoecker@lal2p3.fr

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  1. B Physics, CP Violation and the CKM Fit Andreas Höcker (LAL, Orsay) FNAL Colloquium, May 18, 2005 hoecker@lal.in2p3.fr A. Höcker – B Physics, CP Violation and the CKM Fit …

  2. Outline Themes : • Introduction • CKM phase invariance and unitarity • Statistical issues • CKM metrology • the traditional inputs • deep B physics :, ,  • a new star : B+  + • the global CKM fit • Related topics (radiative B decays and the B  K system) • Preparing the future A. Höcker – B Physics, CP Violation and the CKM Fit …

  3. To start with … • The Universe is empty* ! • The Universe is almost empty* ! Bigi, Sanda, “CP Violation” (2000) • Initial condition ? • Dynamically generated ? Sakharov rules (1967) to explain Baryogenesis • Baryon number violation • CP violation • No thermic equilibrium (non-stationary system) • So, if we believe to have understood CPV in the quark sector, what does it signify ? • A sheer accident of nature ? • What would it do to us if “we set” the CKM phase to zero ? see in this respect: B. Cahn, “The eighteen arbitrary parameters of the Standard Model in your everyday life”, RMP 68, 951 (1996) A. Höcker – B Physics, CP Violation and the CKM Fit …

  4. V.L. Fitch R. Turlay J.W. Cronin J.H. Christenson CP Violation is flavor physics Moments of glory in flavor physics : • Discovery of CP violation (1964) • The smallness of KL  +– predicts charm quark (GIM) • KM theory (to describe CP violation) predicts third quark generation • mK = m(KL) – m(KS) predicts mass of charm quark • Frequency of B0B0 mixing (mB) predicts heavy top quark • Prove of KM theory (sin2) • … ? PRL 13, 138 (1964) [cited: 1067 times] A. Höcker – B Physics, CP Violation and the CKM Fit …

  5. (parenthesis) Evolution of working conditions (example BABAR) : BABAR: PRL 87, 091801 (2001) [cited: 308 times] Belle: PRL 87, 091802 (2001) [cited: 319 times] … 593 physicists (in early 2005). A. Höcker – B Physics, CP Violation and the CKM Fit …

  6. The Search for New Physics in the B System • Since the precise measurement of sin2β in decays (in perfect agreement with the SM), there is considerable effort at B Factories towards the search for specific signs of New Physics (NP).WHY ? • Conflict between limits from flavor physics  1 TeV (e.g., K0, D0, B0 mixing), and NP scale (1 TeV)  NP cannot have a generic flavor structure • The gauge hierarchy Problem (Higgs sector, scale ~ 1 TeV) • Baryogenesis (CKM CPV too small) • The strong CP Problem (why is  ~ 0 ?) • Grand Unification of the gauge couplings • ... many more see, e.g., the instructive talk by Yuval Grossman at LP’03: hep-ph/0310229 A. Höcker – B Physics, CP Violation and the CKM Fit …

  7. New Physics: some possibilities • Minimal flavor violation (MFV) models : CP violation is completely governed by CKM precision tests in rare processes Q : why ? • The NP is essentially flavor blind up to large scales test of CP violation in flavor conserving processes (EDM, …) Q : and what about the leptons ? • Intermediate solutions (example : only b  s transitions are affected by low energy NP), … Q : why would these two families by special ? • … and other still unknown alternatives, which certainly will give the correct answer A. Höcker – B Physics, CP Violation and the CKM Fit …

  8. Im Im Im Q q W– Q CP Violation (Im[...]  0) VqQ q  J/2 J/2   Re Re Re Jarlskog invariant J = 0  no VCP Jarlskog, PRL 55, 1039 (1985) phase invariant : The CKM Matrix and the Unitarity Triangle d s b u c t    A. Höcker – B Physics, CP Violation and the CKM Fit …

  9. If one wishes (not necessary for the analysis), one can Taylor expand in  and finds : digression :The Unitary Wolfenstein Parameterization • The standard parameterization uses Euler angles and one CPV phase  unitary ! • Now, define • And insert into V V is still unitary ! With this one finds (to all orders in ) : where: Buras et al., PRD 50, 3433 (1994) A. Höcker – B Physics, CP Violation and the CKM Fit …

  10. Flavor Physics and CP Violation P940 E787/949 BTEV ATLAS KEK / J-PARC Super-B ? NA48 CLEO-c Super-BABAR ? (?) + EDM experiments at several places in the world Present and future - Worldwide Program on A. Höcker – Mid-Term at the B Factories : the New Picture of CP Violation

  11. The BdSystem(e+e–(4S) factories) the Bd is also produced by the hadron machines A. Höcker – B Physics, CP Violation and the CKM Fit …

  12. CMS ATLAS The Bs System (hadron machines) the Bs is not produced by the (4S)B factories A. Höcker – B Physics, CP Violation and the CKM Fit …

  13. oneandone oneandone oneandone Asymmetric-Energy B Factories (ex. PEP II) e+ e– 3 km Quantum coherence : at t = 0, the system is a superposition of : 9 GeV e– against 3.1 GeV e+ : • coherent production of neutral B pair • boost of (4S) in the laboratory : = 0.56 Einstein-Podolsky-Rosen phenomenon : measurement of flavor of one meson determines flavor of other meson at same proper time; this property is exploited for the “flavor tagging” A. Höcker – B Physics, CP Violation and the CKM Fit …

  14. The Global CKM Fit Inspired by the global electroweak fits A. Höcker – B Physics, CP Violation and the CKM Fit …

  15. Fitting Approach Constraints on theoretical parameters Measurement xexp ytheo = (A,,,,mt,, …) Theoretical predictions = (BK,fB,BBd, …) Xtheo(ymodel= ytheo ,yQCD) yQCD Define: “2” = – 2 lnL(ymodel) L(ymodel) =Lexp[– xtheo(ymodel)]Ltheo(yQCD) ytheo – free parameters (DON’T USE PDFs !) xexp statistical quantities « guesstimates » Frequentist:Rfit Bayesian • experimental likelihood • if not available: Gaussian errors • asymmetric errors • correlations between xexp’s Uniform likelihoods: “allowed ranges” CKMfitter Group and others Probabilities UTfit Collaboration A. Höcker – B Physics, CP Violation and the CKM Fit …

  16. Three-Step CKM Analysis using Rfit Probing the SM Metrology Test New Physics • Define: ymod = {a; µ} = {, , A,,yQCD,...} • Set Confidence Levels in {a} space, irrespective of the µvalues • Fit with respect to {µ} ²min;µ(a) = minµ{²(a, µ) } • ²(a)=²min;µ(a)–²min;ymod CL(a) = 1 –Prob(²(a), Ndof) (or toy MC) • If CL(SM) good Obtain limits on New Physics parameters • If CL(SM) bad Try some other model • Test of “Goodness-of-fit” • Evaluate global minimum ²min;ymod(ymod-opt) • Create perfect data set : xexp-opt = xtheo(ymod-opt) generate xexp usingLexp • Perform many toy fits:²min-toy(ymod-opt)  F(²min-toy) AH-Lacker-Laplace-Le Diberder EPJ C21 (2001) 225, [hep-ph/0104062] A. Höcker – B Physics, CP Violation and the CKM Fit …

  17. m e t r o l o g y Inputs to the Global CKM Fit • |Vud| and |Vus| [not discussed here] • |Vub| and |Vcb| • CPV in K0 mixing • Bd and Bs mixing • sin2 •  : • B • B • B •  : • ADS, GLW • Dalitz • B+  + A. Höcker – B Physics, CP Violation and the CKM Fit …

  18. |Vub /Vcb | sin2 |Vcb| and |Vub| • For|Vcb|and|Vub|existexclusive and inclusive semileptonic approaches d s b exclusive inclusive B Xu ℓ B  ℓ b u u b c c B D* ℓ B Xc ℓ dominant uncertainties t Form factor OPE (|Vcb,ub|) and shape function (|Vub|) • |Vub| ( 2 +2) is crucial for the SM prediction of sin(2 ) • |Vcb| ( A) is important in the kaon system (K, BR(K ), …) A. Höcker – B Physics, CP Violation and the CKM Fit …

  19. (|Vub|) = 5% (|Vcb|) = 5% |Vcb| and |Vub| • Inclusive approaches most appealing at present nonperturbative corrections free quark decay • |Vcb| : moments analyses have 1.5–2% precision ! CKM-05 • |Vub| : reduced conflict between excl. and incl. • SF params. from bcl , OPE from Bosch et al. • reduction of central value 4.6  4.110–3 • ℓ result goes up with Lattice FF (unquenched) CKMfitter average A. Höcker – B Physics, CP Violation and the CKM Fit …

  20. no |Vcb| inclusive CPV in Neutral Kaon Mixing • Neutral kaon mixing (FCNC) mediated by box diagrams effective matrix element • Most precise results from amplitude ratio of KL to KS decays to +– and 00 • ij from perturbative QCD • improvement on BKfrom Lattice QCD (quenched) reported at CKM-05 : BK = 0.79 ± 0.04 ± 0.09 (now also Nf=2heavy calc. available) A. Höcker – B Physics, CP Violation and the CKM Fit …

  21. [B=2] [B=2] + B0 Mixing • Effective FCNC Processes (CP conserving –– top loop dominates in box diagram): Perturbative QCD CKM Matrix Elements Non-perturbative: Lattice (eff. 4 fermion operator) Loop integral (top loop dominates) • Dominant theoretical uncertainties : consider in fit that Lattice results are correlated ! • Improved error indirect via ms : [SU(3) breaking correction] A. Höcker – B Physics, CP Violation and the CKM Fit …

  22. No signal yet for Δmsupper limit : Δms > 14.5 ps–1 at 95% CL [ CDF: WA sensitivity 18.1  18.6 ps–1 ] CKM fit predicts : Δmd = 18.3 ps–1 + 6.5 – 2.3 Δms known future B0 Mixing • Δmd = (0.510 ± 0.005) ps–1 [ CKM constraint dominated by theory error ] CKM fit predicts : Δmd = 0.47 ps–1 HFAG – Winter 2005 + 0.23 – 0.12 A. Höcker – B Physics, CP Violation and the CKM Fit …

  23. sin(2)[ the first UT input that is not theory limited ] Principal modes :  Tree : dominant Penguin : dominant A. Höcker – B Physics, CP Violation and the CKM Fit …

  24. CP-Violation Primer • Condition for CP invariance : • Definition of “CP parameter” : decay amplitude ratio CP eigenvalue • CP invariance requires : • Classification of CP violation : CP violation in mixing (”indirect”) : CP-violating phenomena CP violation in the decay (“direct”) : CP violation in interference between mixing and decay : A. Höcker – B Physics, CP Violation and the CKM Fit …

  25. Direct CP Violation • First seen by NA48 and KTeV in kaon system (’) • Large asymmetry observed by BABAR and Belle in B0  K+– decays : BABAR … none. • Direct CPV requires interference of amplitudes of similar size and with different weak and strong phases cannot be reliably predicted (at present) for use in CKM fit A. Höcker – B Physics, CP Violation and the CKM Fit …

  26. BABAR BABAR BABAR CP mixing decay CP = –1 (J/ KS …) CP = +1 (J/ KL …) Mixing-Induced CP Violation • CP Violation due to the interference of decays with and without mixing • Time-dependent asymmetry observable CP observables with : = sin(2) and = 0 for b  ccs, sss A. Höcker – B Physics, CP Violation and the CKM Fit …

  27. S I N 2  I S N O T A G O L D E N M O D E ! Mannel at CKM 2005 • Conflict with sin2efffrom s-penguin modes ? Beneke,hep-ph/0505075 I T ‘ S P L A T I N U M ! (*) (*)Thomas Mannel at CKM-05 ? sin(2)eff[s-penguin] careful with this average ! ? ? ? sin2[ first UT input that is not theory limited ! ] • “The” raison d’être of the B factories : Theory uncertainty ? HFAG – Winter 2005 A. Höcker – B Physics, CP Violation and the CKM Fit …

  28. Principal modes : Not a CP eigenstate  [ next UT input that is not theory limited ]  Penguin : competitive ? Tree : dominant A. Höcker – B Physics, CP Violation and the CKM Fit …

  29. “T” and “P” are of the same order of magnitude : [Note that T and P are complex amplitudes !] Direct CP violation can occur : ! where is the relative strong phase realistic scenario Charmless b u Decays • Tree “T” amplitude dominates No direct CP violation : • Time-dependent CP observable : ideal scenario A. Höcker – B Physics, CP Violation and the CKM Fit …

  30. Isospin Analysis for B,  Unknowns Observables Constraints Account , T+–, P+–, T+0, P+0, T00, P00 B+–, S , C B+0, ACP B00, (S00),C00 2 isospin triangles and one common side 13unknowns – 7 observ. – 5 constraints – 1 glob. phase = 0  Assumptions: • neglect EW penguins (shifts  by ~ +2o)penguins • neglect SU(2) breaking • in ρρ: Q2B approx. (neglect interference)  can be resolved up to an 8-fold ambiguity within [0,] Refs. for SU(2) analyses : Gronau-London, PRL, 65, 3381 (1990), Lipkin et al., PRD 44, 1454 (1991), a.o. A. Höcker – B Physics, CP Violation and the CKM Fit …

  31. CP Results for B0+– • Results for the time-dependent analysis : BABAR, hep-ex/0501071 Belle, hep-ex/0502035 Mediocre (but improved) agreement : 2 = 7.9 (CL = 0.019  2.3σ) A. Höcker – B Physics, CP Violation and the CKM Fit …

  32. BABAR & Belle BABAR & Belle note yet updated with new result from Belle σ(S+–)= σ(C+–)~0.01 penguin / tree • Study decay dynamics ... B Isospin Analysis • 2 fit of isospin relations to observables: BABAR A. Höcker – B Physics, CP Violation and the CKM Fit …

  33. B+– = (30 ± 6)10–6 , B00 < 1.110–6 at 90% CL A “surprise” : the B Isospin Analysis • Nature’s great present : longitudinal polarization dominates  almost no CP dilution • Rates for the B  system :  small penguins ! BABAR, hep-ex/0412067 • Results from CP fit : BABAR, hep-ex/0503049 • Isospin analysis : penguin / tree As expected: much smaller than in B  A. Höcker – B Physics, CP Violation and the CKM Fit …

  34. CP mixing The B System • Dominant mode ρ+– is not a CP eigenstate Aleksan et al, NP B361, 141 (1991) • Isospin analysis requires to constrain pentagon Lipkin et al., PRD 44, 1454 (1991) • 13 observables vs 12 unknowns  • needs statistics of Super-B  [systematics?] • Better: exploit amplitude interference in Dalitz plot Snyder-Quinn, PRD 48, 2139 (1993) BABAR • simultaneous fit of  and strong phases • BABAR determines 16 (27) FF coefficients • correlated 2 fit to determine physics quantities 00 +– –+ A. Höcker – B Physics, CP Violation and the CKM Fit …

  35. Results of B0()0 +–0 Dalitz analysis • From the 16 FF coefficients one determines the physical parameters : Parameters : , |T+–|,T–+,T00,P+–,P–+ Direct CP violation ? Scan in  using the bilinears : Δχ2(no direct CPV) = 14.5 (CL = 0.00070  3.4σ) A+– no direct CPV BABAR A–+ BABAR, hep-ex/0408099 A. Höcker – B Physics, CP Violation and the CKM Fit …

  36. similar precision as CKM fit : CKM fit (no ,  in fit) Combination of, ,  : first measurement of  • Combining the three analyses (B   best single measurement) : mirror solution disfavored for the SM solution we find : A. Höcker – B Physics, CP Violation and the CKM Fit …

  37. digression : “Color-Suppressed” Amplitudes Famous modes : • The color of the quarks emitted by the virtual W must correspond to the external quark lines to produce color-singlets  suppressionby ~1/Nc(naïve!) [ Suppression  verified in B(B0  D00)/B(B0  D–+) = (1/10.4)exp  (1/Nc)2 ] important non-factorizable contributions when large penguins ? Large u-penguins ? A. Höcker – B Physics, CP Violation and the CKM Fit …

  38.  [ next UT input that is not theory limited ] • GLW : D0 decays into CP eigenstate • ADS : D0 decays to K–+ (favored) and K+– (suppressed) • GGSZ : D0 decays to KS+– (interference in Dalitz plot) • All methods fit simultaneously: , rB and  the million dollar Q: Gronau-London, PL B253, 483 (1991); Gronau-Wyler, PL B265, 172 (1991) Atwood-Dunietz-Soni, PRL 78, 3257 (1997) Giri et al, PRD 68, 054018 (2003) No Penguins  relative CKM phase :  Tree: dominant Tree: color-suppressed A. Höcker – B Physics, CP Violation and the CKM Fit …

  39. “ADS+GLW” : Constraint on  • BABAR and Belle have measured the observables for GLW and ADS in the modesB– D0K–, D*0K–, D0K*– not yes used • No significant measurement of suppressed amplitude yet  limit : rB(*) 0.2 BABAR, hep-ex/0408082, 0408060, 0408069, 0408028 Belle, Belle-CONF-0443, hep-ex/0307074, 0408129 for the SM solution : not yet competitive with CKM fit A. Höcker – B Physics, CP Violation and the CKM Fit …

  40. Measurement of amplitude ratio: [ no improved constraint when adding  from CKM fit ] “GGSZ” : Constraint on  • Promising : Increase B decay interference through D decay Dalitz plot with D0 KS+– • huge number of resonances to model: K*(892), (770), (782), f0(980,1370), K0*(1430), ...  • amplitudes of Dalitz plot measured in charm control sample  A. Höcker – B Physics, CP Violation and the CKM Fit …

  41. B+ + • A new star at the horizon; helicity-suppressed annihilation decay sensitive to fB|Vub| • Powerful together with Δmd : removesfBdependence • Sensitive to charged Higgs replacing the W propagator • Best current limit from BABAR : M. Datta, SLAC seminar 2005 • Prediction from global CKM fit : A. Höcker – B Physics, CP Violation and the CKM Fit …

  42. Putting it all together t h e g l o b a l C K M f i t Inputs: Perfect agreement … if it weren’t for the s-penguin decays A. Höcker – B Physics, CP Violation and the CKM Fit …

  43. 2nd solution Putting it all together the impact of the unitarity triangle angles  The angle measurements dominate ! A. Höcker – B Physics, CP Violation and the CKM Fit …

  44. Consistent Predictions of all CKM-related Observables FOR UPTODATE RESULTS CHECK THE CKMFITTER WEB numerical results at: http://www.slac.stanford.edu/xorg/ckmfitter/ and http://ckmfitter.in2p3.fr/ (mirror) A. Höcker – B Physics, CP Violation and the CKM Fit …

  45. There’s much more in it … Other CKM-related topics not discussed in this colloquium : • super rare kaon decays : K  • charged decay already seen by E787, E949) • radiative and leptonic B decays : B , B K*, b  s, … • model-independent analysis of new physics in mixing and decay E787, PRL 88, 041803 (2002) E949, PRL 93, 031801 (2004) next pages Dynamical analysis of B , K, KK decays under different hypotheses Most simple charmless B decays; theory understanding must start here • SU(2)  done for , not fruitful for K at present • SU(3) • QCD Factorization next pages Puzzle ? A. Höcker – B Physics, CP Violation and the CKM Fit …

  46. B   observation should be imminent! Belle BABAR Radiative Penguin Decays • Radiative penguin decays B   ( |Vtd|2) and B  K*( |Vts|2) sensitive to New Physics • Ratio of BRs predicted more cleanly than the individual rates: SU(3) breaking correction Ali, Parkhomenko, EPJ C23 (2002) 89 Bosch, Buchalla, NP B621 (2002) 459 (and later papers); errors from CKM 05 90% CL • So far only upper limit for B   90% CL BABAR, PRL 94, 011801 (2005) Belle, hep-ex/0408137 (prelim.) Charged modes larger limit: , but less theoretically clean A. Höcker – B Physics, CP Violation and the CKM Fit …

  47. “” from B  00, K00, K+K– • interesting combined constraint in (,) plane • “” from B  +–, K+–, K+K– digression : Puzzling B, K, KK Decays : SU(3) • About puzzles : • there is a puzzle: why are “color-suppressed” terms (or u-penguins) so large ? • there isnoK puzzleusing SU(2) [quadrilateral system not constraining enough – 9 params vs. 9 obs] • there seems to beaK puzzleusing SU(3) when neglecting annihilation terms and PEW,C Silva-Wolfenstein, 1993 Buras et al. (BFRS), EPJ C32, 45 (2003) Chiang et al, PRD D70, 034020 (2004) Wu-Zhou, hep-ph/0503077 Charles et al., EPJ C21, 225 (2001) Charles-Malclès-Ocariz-AH, in preparation apologies to the many other authors on this problem • Complete analysis in strict SU(3) limit • Global analyses: • at present: 13 parameters vs. 19 observables • when everything is measured (incl. Bs) : 15 parameters vs. ~ 50 observables A. Höcker – B Physics, CP Violation and the CKM Fit …

  48. digression : Puzzling B, K, KK Decays : QCDF • Several theoretical tools exist for nonleptonic B decays. All are based on the concept of Factorization • QCD FA • pQCD • SCET including the treatment of charming penguins by Ciuchini et al. Beneke et al, PRL 83, 1914 (1999); NP B675, 333 (03) Keum et al, PLB 504, 6 (2001); PRD 67, 054009 (03) Bauer et al, PRD 63, 114020 (2001) “Color Transparency” • With conservative error treatment, only a data-driven fit is predictive Is there a puzzle ? A. Höcker – B Physics, CP Violation and the CKM Fit …

  49. assumptions: And the near Future ? t h e g l o b a l C K M f i t i n 2008 Inputs: ?...? A. Höcker – B Physics, CP Violation and the CKM Fit …

  50. Zfitter I N S P I R E D CKMfitter MNSfitter Sfitter GUTfitter HEPfitter COSMOfitter and the far … F U T U R E NA48 t h a n k y o u A. Höcker – B Physics, CP Violation and the CKM Fit …

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