Outline Introduction & definitions Experimental observables related to a and g

1. CKM Unitarity anglesa (f2) and g (f3)(Recent results from the B factories.)Hassan JawaheryUniv. of MarylandLepton-Photon SymposiumFermi National Accelerator LaboratoryAugust 12, 2003 Outline • Introduction & definitions • Experimental observables related to a and g • Experimental results, some discussion of implications for SM & constraints on a and g

2. Definitions CP The Unitarity Test Both involve Vub f1=b f2=a f3=g

3. Constraints from the CKM fit |Vub|, |Vcb|, eK, Dmd , Dms Indirect info on angles At 95% C.L. A. Hoecker et al, Eur. Phys. Jour. C21 (2001) 225, [hep-ph/0104062] • Unitarity Tests : Search for deviation from SM • Using direct measurements of angles check: a + g + b=p • Check if B Decays are consistent with the range of angles from the CKM fit?

4. Main source of info on a and g:Decays involving bu transitions I- Charmless B Decays Tree diagrams are not alone: Penguins (gluonic & E.W) can also lead to the same decays: d Bp p: (p+ p-, p+ p0, p0 p0 ) Brp, B r r, a1p,…. Data indicate gluonic penguins are large & complicate extraction of a Interference of T & P results in Direct CP violation & sensitivity to g s BKp: (K+ p- , K0 p+ , K0 p0 ,..) CKM suppressed

5. II- Decays involving interference of bu W- & bc W- Processes (Penguin Free) BDK: Involves arg(Vub)=g g dependence of rate and direct asymmetry + B- DCPK- Same final state via B0 mixing & bu B0D- p+: + Direct CP asymmetry sensitive to sin(2b+g) arg(Vub)=g

6. Experimental Observables • Branching fractions for various non-charm B decays • Time Integrated (Direct) CP asymmerties With Tree and Penguins both in action: To constrain g requires estimates of: | Ppp/Tpp|& relative strong phase d

7. Time evolution of tagged B0 decays, e.g. in the case of B0p+p- More observables: Time – Dependent CP Asymmetries CPV due to mixing and decay interference Direct CPV in Decay Belle: Af = - Cf (BaBar) With Tree alone S=sin2aeff Da=aeff –a C 0 With Penguin and Tree

8. A few comments on the already established pattern from charmless 2-body decays Connected via Isospin symmetry (Gronau &London) (Isospin engineering) Constructing these triangles is a major goal of the experiments Control rescattering effects Da (P & T) (P & T) (T) (P’ & T’) With Tree alone,expect: (P’ & T’) (P’ & T’) (P’) Measurements: Penguins are significant players P’ & use SU(3)connections to estimate P

9. Goals and Issues on the Measurement Side • Search for CP violation: Direct (C 0) & Indirect (S0) deviating from (sin2b): [i.e. indirect CPV outside of mixing phase.] • Measure/Constrain a & g using many different modes and exploit the redundancy to resolve the ambiguities. • The reality (Considering the presences of large Penguin effects) • No single measurement is expected to lead to determination of a & g • Need info from many decay modes and the emerging pattern & connections via symmetries, [isospin, SU(3) ], and eventually more predictive theories [perhaps QCD factorization or perturbative QCD- when verified ] to constrain various components of the problem. The job description Eventually a & g Keep finding the pieces of the charmless puzzle

10. Experiments and Data The focus of this talk The B physics reach of hadron machines & current status covered by Kevin Pitts . Next Talk

11. Analysis Issues for Rare B Charmless decays • Looking for modes with Br~10-6 to 10-5 • Continuum qq(bar) background at 103 larger than the signal • BKG Suppression using event shape & topology, kinematics, particle ID,.. Signal Monte Carlo Kinematic variables: DE=Ebeam-EB provides separation of KK, Kp, pp decays p- • Other info into analysis: • Dt=Dz/<cgb> • Flavor tag of other side • Particle ID, event shape,.. p+

12. The road to a: Measurement of CPV in Bp+ p- Isolation of Signals BaBar: 81 fb-1 Belle 78 fb-1 p+p- Kp ~200 Bp+ p- Per experiment p+p- p+p- Kp Kp

13. Time Dependent CPV in Bp+ p- 0 0 -5 -5 5 5 Fits to: 78 fb-1 81fb-1 (BaBar) (Belle) B0 tag B0 tag Asymmetry Events/1ps Dt(ps) Dt(ps)

14. New Results:BaBar Update of CPV measurements with full data sample (Run 1+2+3): 113 fb-1 on Peak data • Reprocessed Run1+2 (82 fb-1 ) • Added Run 3 ((31 fb-1 ) B0 tag B0 tag New CPV Results Run1+2(reprocessed) S=-0.252±0.27 C=-0.166 ±0.22 Run 3 S=-0.67±0.35 C=-0.33 ±0.34

15. Summary of CPV in Bp+ p-: Belle’s update with their full data set awaited Current world average (with BaBar new results) S=-0.58±0.20 C=-0.38 ±0.16 Ignoring the large c2 ~6.3 (~2 s) Too early to claim observation of CPV in Bp+ p- :Direct (in decay) or Indirect(mixing & decay) S & C not enough to measure a: Need Da=aeff – a, which requires the other pieces of the isospin analysis.

16. BaBar: The decay Bp0 p0 • Used their full data set (113 fb-1 ) • Measured Br(Br+p0) [Br(Br+p0 ) =(112.7)x10-6 ] Control over a major background source. Br about half of previous assumed value signal qq bkgd r+p0 Fischer Discriminant Significance: 4.2 s Observation

17. Belle: The decay Bp0 p0 Analyzed full data set of 140 fb-1 From a fit to 2-dimensional distribution of Mes and DE Find: Significance:3.4 s Evidence

18. What about Da: All but one piece is in place Branching ratios (x10-6) For a full Isospin analysis need: Cp0p0 (direct CPV) & Still some constraint can be set using the measured average Branching fraction: Da (Quinn- Grossman), With WA Br(B p0 p0 ) |a-aeff |<48o at 90% c.l. Not a very useful limit & don’t expect more than ~10o improvement in future. Not much improvement on QG bound

19. Summary of measurements of Bpp & Kp Decays See John Fry’s talk this morning for more detail &comparison with Theory Thanks to Heavy flavor averaging group(HFAG): Rare decays: J. Smith (colorado), J. Alexander(Cornell), P.Chang (KEK) Evidence Direct CPV ?

20. What did we learn about a & g? Is this all consistent with Standard Model? Does it accommodate the range of UT angles from the global CKM fit?

21. Cppvs Spp : Allowed range & comparison with SM ( CKM fit) Gronau and Rosner approach (PRD 093012) |P / T | estimated using B->K0+ & Bpln , B p0+ (with use of SU(3) & factorization) Here calculate S & C for |P/T|~0.3 Unconstrained strong phase d BaBar BaBar Belle My Average Physical boundary Data consistent with SM (CKM fit)

22. A more optimal use of information using the CKMfitter tools with various assumptions (LAL 02-103: Authors Hoecker, Lacker, Pivak, Roos). SU(3) & some use of QCD Factorization to estimate SU(3) breaking effects In all scenarios data can accommodate the range of a from the SM CKM fit

23. Constraints on g: Connecting the BKp data via symmetries Useful ratios of branching fractions and ps-asymmetries with sensitivity to g: Rosner, Gronau, Neubert, Fleischer, Mannel, .. |T/P| Size of EW penguins Ratios using HFAG averages: R0=0.99±0.09 A0= - 0.09 ±0.03 Rc=1.30±0.15 Ac=0.0 ± 0.06 Rn=0.8 ±0.11 An=-0.07 ± 0.03 All shown to accommodate range of g from CKM fit (Fleischer), (Gronau, Rosner),…

24. Gronau & Rosner method hep/ph-0307095 (R0 vs g) for fixed A0 A0=-0.06(A0+1s) R0 R0 1 s range of R0 A0=-0.12(A0-1s) g Consistent with CKM range: 60 < g <120 at 1 s level No useful limit at 2 s level

25. Other channels of reaching a: • B (ppp):CPV studies require isolation of states with specific CP parity: e.g. B (r+p- + r-p+) using Dalitz plot analysis. • Interference between (r+p- + r-p+)can be used to determine a even in the presence of penguins [Quinn-Snyder] • BaBar has presented CPV results based on quasi 2-body decays B0”r+ “p-,B0”r-”p+ --updated for this conference with their full data sample. • 1st Belle results on CPV with these modes expected soon. • Components of the Isospin analysis (pentagon) are also being measured. (J. Fry’s talk today) • B(pppp): e.g. Brrhas been measured and shown to be dominated by the CP even component – good news for CPV studies.

26. CPV Studies with the decay B0rp Not a CP eigenstate & involves more observables: Summing over the r charge: Direct CP violation: Crp Indirect CP (mixing and decay):Srp Charge Asymmetry: Dilution (Non CP parameters): DCrp & DSrp

27. BaBar results on CPV in Brp: 113 fb-1 rp rK rp rK

28. New Results PRL 2.3s (Stat. only) Test Of Direct CPV Define two asymmetries: 2.5s (2.7s if stat. only) 90% 98.6% 99%

29. A promising channel:the Brr system The components of Brr are identifeid: B0r+r-(BaBar),B+r+r0 (Belle & BaBar) Decays nealy 100% longitudinally polarized [CP-even] Limit has been set on B0r0r0. See John Fry’s talk this morning for more detail Quinn-Grossman bound applied to the longitudenal polarization component of the rates: >2 times more restrictive than Bpp system The Channel to watch in Future

30. Reaching g via (bu(cs) & bc(us) interference: BDK Decays Method and observables suggested by Gronau, Wyler,Atwood,Dunietz, Soni,Quinn, Sanda

31. BDK Modes- No penguins In B- DCPK- , the diagramsinterfere & provide the sensitivity to  : [DCP=(1/2)(D0D0 ) ] DK triangle Observables Also unknown rDK (~0.1 –0.2) & dDK Experimenters are very active in constructing the DK puzzle

32. D1=K+K-, p+p- 13.14.34.3 D2=Ksp0, Ksf, Ksw 7.23.6 2.4 B-→DCPK*- D0 → K, K,K 0 coshel from P→PV MK*- B0 → DK0 B- → D*0 K*- D*0 → D0 B → D*0 K*-ALL D*0 → D00

33. BDoK- The BDK puzzle under construction Vub BDoK*- Vub (8.3 ± 1.1(stat) ± 1.0(sys)) x 10-4 & GL/G=0.86 ±0.06 ±0.03 (BaBar) (7.7 ± 2.2(stat) ± 2.6(sys)) x 10-4 CLEO

34. What about g: Current errors are still too large to allow for simultaneous extraction of g & ratio of (bc) and (bu) amplitudes (rdk) and the strong phase. Need many fold more data. (dg~20 may be possible with 500 fb-1) With assumptions on (rdk): mild limits can be extracted. e.g M. Gronau (hep-ph/0306308): g>72oat 1 sigma level.

35. Reaching sin(2b+g) via (bu(cd) & bc(ud) interference (& B0 mixing) B0D(*+) p- Method and observables first suggested by Sachs,Dunietz

36. B0D(*+)- Modes Dominant diagram b  c transition Suppressed diagram b  u transition Small asymmetry expected Time evolution:

37. 2b+g BaBar I- Partially reconstructed B0D*+- Decays: (number of events) Lepton tags kaons tags II - Fully reconstructed B0D(*+)- Decays Belle Fully reconstructed B0D(*+)- Decays

38. Interpretation:BaBar’s attempt Use measurements of B0D(*+)sp+to estimate r(*) (Factorization & SU3 correction ) Favors the CKM favored solution to sin2b

39. Summary & Conclusions • Major progress made in probing the charmless sector of B decays for information on unitarity angles a & g: • New updated measurements of CPV in B p+p- still show no significant evidence for CP violation in this mode. • Observation of Bp0 p0 – a missing component of Tree/Penguin disentanglement plan. • CPV studies in Brp shows hints of direct CP violation. • The decay Brr is now measured and looks promising for CPV studies and constraining a. Indications that penguins are smaller. • Indication of direct CPV in BK-p+ (WA: Belle, BaBar, CLEO) No indication for large direct CP yet. • The emerging constraints on the angles from the pattern of data are consistent with the favored range from the CKM picture in the Standard Model. • Penguin free modes (BDK & D*p) are beginning to contribute to constraints on CKM parameters & many new BDK modes identified. • Much more data & major progress in theoretical understanding of hadronic B decays needed to complete the picture and conclusively perform the CKM unitarity test.