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Recent results on CP violation in B decays

Recent results on CP violation in B decays. Marcello A. Giorgi Università di Pisa and INFN Pisa presented at XXXII International Conference on High Energy Physics Beijing, China August 16-22, 2004. Current luminosities and data samples. Delivered. Recorded. Continuum. 300. 250. 200.

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Recent results on CP violation in B decays

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  1. Recent results on CP violation in B decays Marcello A. GiorgiUniversità di Pisa and INFN Pisa presented at XXXII International Conference on High Energy PhysicsBeijing, ChinaAugust 16-22, 2004

  2. Current luminosities and data samples Delivered Recorded Continuum 300 250 200 150 100 50 0 10/11/04 9/11/00 1/21/02 5/3/99 6/2/03 Total 244 + 286 fb-1 = 0.530 ab-1!! 22fb-1/month 17fb-1/month Marcello A. Giorgi

  3. BABAR Detector EMC 6580 CsI(Tl) crystals e+ (3.1GeV) 1.5T solenoid DIRC (PID) 144 quartz bars 11000 PMs Drift Chamber 40 layers e- (9GeV) Silicon Vertex Tracker 5 layers, double sided strips Instrumented Flux Return iron / RPCs (muon / neutral hadrons) Marcello A. Giorgi

  4. CKM and unitarity conditions Marcello A. Giorgi

  5. 3 ways for CP violation q/p q/p  A A 2 2  First mechanism observed historically in kaon decays 1. CP violation in mixing SM predicts: 2. Direct CP violation in the decay Occurs when where A is the amplitude for B decays into a final state f and A is the amplitude of B decays into the CP conjugate state f. Two amplitudes A1 and A2 with a relative CP violating phase f2 and a CP conserving phase d :CP violation and. Marcello A. Giorgi

  6. First observation of Direct CPV in B decays BABAR hep-ex/0408057, submitted to PRL BABAR 4.2s Belle Confirmation at ICHEP04 3.9s Average 3.6s Average Marcello A. Giorgi J. Wu, Y.Chao, CP-6

  7. 3 ways for CP violation B0 fCP B0 Decay+mixing B0 fCP No oscillation B0 Net oscillation 3.Time dependent Define CP Asymmetry as: Decay+mixing No oscillation Net oscillation For single amplitude Amplitude ratio CP parameter Marcello A. Giorgi

  8. Measuring time-dependent CP asymmetries z FlavorTagging Tag vertex reconstruction Exclusive B Meson and vertex reconstruction Tagging performance: Q = 30.5% Dz Start the Clock Marcello A. Giorgi

  9. sin2b results from charmonium modes bkg Limit on direct CPV Belle 2003 BABAR Update for ICHEP04 Belle CONF-0436 BABAR PUB-04/038 Marcello A. Giorgi M.Bruinsma, T. Higuchi, CP-3

  10. sin2β, cos2β and CKM constraints BABAR cos2b < 0 ruled out at 87% CL by s- and p-wave interference analysis in angular analysis of BJ/yK*0 (KSp0) cos2β < 0 cos2β > 0 M.Bruinsma, CP-3 CKM fit to indirect constraints overlaid with sin2βWA measurement Marcello A. Giorgi

  11. Methods for extraction of g Basic Idea Color suppressed GLW Gronau-London-Wyler, 1991 Atwood-Dunietz-Soni, 2001 ADS D0 Dalitz plot Marcello A. Giorgi

  12. B- D(*)0[K+p-]K- decays: ADS method BABAR Update for ICHEP04 Belle BABAR CONF-04/013 Marcello A. Giorgi G.Cavoto, A.Bozek, CP-4

  13. First look at B- D(*)0[KSp+p-]K- sample by Belle M2(KSp-) [GeV2] M2(KSp-) [GeV2] M2(KSp+) [GeV2] M2(KSp+) [GeV2] M2(KSp-) [GeV2] M2(KSp-) [GeV2] M2(KSp+) [GeV2] M2(KSp+) [GeV2] Belle 140 fb-1 New: Winter 04 Visible asymmetry in Dalitz plots hep-ex/0406067 Marcello A. Giorgi A.Bozek, CP-4

  14. BABAR analysis of B- D(*)0[KSp+p-]K- 68% 90% New for ICHEP04 BABAR g [deg] g [deg] [No sensitivity to rB < 0.1] Poor constraints on g as yet BABAR CONF-04/043 Marcello A. Giorgi G.Cavoto, CP-4

  15. sin2 from B  , ,  Interference of suppressed b  u “tree” decay with mixing but: “penguin” is sizeable! B0 decay: penguin B0 mixing B0 decay: tree Coefficients of time-dependent CP Asymmetry With no penguins With large penguins and |P/T| ~ 0.3 Marcello A. Giorgi

  16. Results for sin2eff from B   decays BABAR: Updated for ICHEP04 BABAR Belle: PRL 93 (2004) 021601 BABAR CONF-04/047, 04/035 Comparison Caution averaging! Marcello A. Giorgi M.Cristinziani, CP-5

  17. Result for B p0p0 First measurements First measurements Updated for ICHEP04 BABAR CONF-04/035 Improved understanding of p0 efficiency: 4.9s 6.0s Consistent at 1.3s level Marcello A. Giorgi M.Cristinziani, CP-4; Y.Chao, CP-6

  18. Results for sin2eff from B  rr decays Extraction of a similar to pp, but with advantage of smaller Penguin pollution: BABAR Moriond QCD04 Marcello A. Giorgi C.Dallapiccola, CP-6

  19. Isospin Corrections for a PRL 91 (2003) 171802 BABAR Updated for ICHEP04 BABAR CONF-04/037 Compare with 35o for pp Geometric limit on 2dapeng: Grossman-Quinn bound Marcello A. Giorgi C.Dallapiccola, CP-6

  20. Basis for Dalitz plot analysis of B0  (rp)0 r0p0 r+p- Quasi-two-body approach to Snyder-Quinn method Phys.Rev. D 48, 2139 (1993) • Extract a and strong phases using interference between amplitudes • Amplitude A3p dominated by r+p-, r-p+,r0p0 and radial excitations • Form time-dependent decay rate coefficients of cos(DmdDt) and sin(DmdDt) on this basis r-p+ Marcello A. Giorgi

  21. Results from Dalitz analysis of B0  (rp)0 BABAR combined 3.6s Evidence for direct CP: 2.9s BABAR [Based on factorization & SU(3); Gronau & Zupan] hep-ex/0408003 BABAR CONF-04/038 Marcello A. Giorgi M.Cristinziani, CP-5; A.Somov, CP-6

  22. Summary of constraints on a BABAR & Belle combined Mirror solutions disfavored Marcello A. Giorgi

  23. CKM constraints and sin2b and a measurements CKM fit to indirect constraints overlaid with sin2βWA and a measurements Marcello A. Giorgi

  24. Do and yield the same sin2b ? Beyond the Standard Model?

  25. sin2b and..... and.... In SM interference between B mixing, K mixing and Penguin bsss or bsdd gives the same e-2ib as in tree process bccs. However loops can also be sensitive to New Physics! New phases from SUSY? Marcello A. Giorgi

  26. BABAR results for B0fK0 2004 = 227MBB pairs(2003 = 120M pairs) 2003 result BABAR Update for ICHEP04 - BABAR-CONF 04/033 Marcello A. Giorgi A.Hoecker, CP-4

  27. More BABAR results from b  sss penguins Update for ICHEP04 BABAR CONF-04/025 BABAR • Independent sample with (K+K-) mass outside f region • CP content can be determined experimentally with an angular moment analysis through the helicity angle distribution Marcello A. Giorgi A.Hoecker, CP-4

  28. More BABAR results from b  sss penguins CONF 04/040 CONF 04/019 BABAR BABAR Updates for ICHEP04 Marcello A. Giorgi A.Hoecker, CP-4

  29. Still another penguin mode: B0 p0KS y x Beam constraint BABAR technique from 2003 Updated for ICHEP04 BABAR CONF-04/030 BABAR [sPlots: Pivk, Le Diberder, physics/0402083] Belle BABAR Marcello A. Giorgi A.Hoecker, CP-4; C.F. Chen, CP-3

  30. Results on sin2b from s-penguin modes 2.7s from s-penguin to sin2b (cc) 2.4s from s-penguin to sin2b (cc) All new! All new! Marcello A. Giorgi

  31. Projections for Penguin Modes f0KS KSp0 jKS h’KS KKKS Luminosity expectations: 2004=240 fb-1 2009=1.5 ab-1 K*g Similar projections for Belle as well 5s discovery region if non-SM physics is 20% effect 2004 2009 Projections are statistical errors only; but systematic errors at few percent level Marcello A. Giorgi

  32. Conclusions and outlook • Success of B Factory experiments BaBar and Belle of bccs (new sin2b value from charmonium 0.726 ± 037) • Good agreement between BaBar and Belle results on bsss penguin, but both experiments still show discrepancies (2.7 and 2.4s) with charmonium!! • Observation by BaBar of the direct CP violation in charmless B decay confirmed by Belle (average value ) • Quantitative measurements of a (f2) are emerging (new value ) • Constraints on g (f3) are still poor with present statistics (low values for rB). • A statistical increase on these modes in the next few years could well provide initial evidence for new physics in the unitarity triangle beyond the SM. • Modes dominated by penguin amplitudes as B0  fK0 seem to be promising benchmarks for New Physics at a mass scale < 1 TeV.However unravelling the full flavour impact of this new physics will require a very high luminosity B Factory – a Super-B Factory – (luminosity higher by a factor 50-100 than in the present machines). Marcello A. Giorgi

  33. Backup Slides

  34. Results on sin2b from ccs, dcc modes Marcello A. Giorgi

  35. B flavor tagging and Dt measurement Tagging performance QT=30.5% (6 categories) from full Neural Network including these & other physics processes to identify b quark state perfect resolution smeared resolution t resolution dominated by tag side: s(Dt)  1 ps  170 m B  1.6 ps  250 m CP asymmetry Marcello A. Giorgi

  36. cos2b from B0 → J/yK*0(KSp0) • J/yK*0 (KSp0) final state can be hF = +1 or hF = -1, depending on L = 0, 1, 2 • Full angular analysis allows for the separation of CP even (A||=| A|| | e id ||, A0 =| A0 | e id 0)and CP odd (A =| A | e id ) • Many terms in time-dependent decay rate, but two are proportional to cos2β BABAR BABAR (with sin(2β) fixed to 0.731) Sign ambiguity is related to the sign of strong phase difference • Use interference of s-wave and p-wave contributions to Kp final state to resolve sign ambiguity for strong phases ○ solution 1: unphysical solution ● solution 2: physical solution ○ LASS data Marcello A. Giorgi

  37. Dalitz analysis of B- D(*)0[KSp+p-]K- 2 Schematic view of the interference Marcello A. Giorgi

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