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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 Laboratori Nazionali di Frascati October 5, 2004 Mini Workshop on B-Factories. The CKM picture with 3 quark doublets. CP mirror. Cabibbo-Kobayashi-Maskawa matrix

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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 Laboratori Nazionali di Frascati October 5, 2004 Mini Workshop on B-Factories Marcello A Giorgi

  2. The CKM picture with 3 quark doublets CP mirror Cabibbo-Kobayashi-Maskawa matrix • quark charged currents <=> W • left-handed (qj=d,s,b) quark mass eigenstates connected to weak eigenstates; • Unitary (FCNC suppressed)=>4 independent parameters (e.g., 3 angles and 1 phase) • Phase changes sign under CP • Interfering amplitudes can give CP-violating asymmetries Marcello A Giorgi

  3. From Unitary CKM matrix to Unitarity Triangles From unitarity condition . Marcello A Giorgi

  4. 3 ways for CP violation q/p q/p  SM predicts: A A 2 2 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. First mechanism observed historically in kaon decays 1. CP violation in mixing Two amplitudes A1 and A2 with a relative CP violating phase f2 and a CP conserving phase d :CP violation and. Marcello A Giorgi

  5. 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 J. Wu, Y.Chao, CP-6 Marcello A Giorgi

  6. 3 ways for CP violation B0 fCP B0 Decay+mixing B0 fCP No oscillation B0 Net oscillation Decay rates of B0 ad B0 are: 3.Time dependent Decay+mixing Define CP Asymmetry as: No oscillation Net oscillation For single amplitude Amplitude ratio CP parameter Marcello A Giorgi

  7. 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

  8. Tools to measure time dependent Asymmetries • Precise measurement of decay points of boosted B0B0 system. • First projects of precise vertexing method: • vertex separation decay time measurement in • boosted heavy mesons and first Si strip detectors • before any industrial development in 1980 • SILICON 'MULTIWIRE PROPORTIONAL CHAMBERS' AND THEIR • APPLICATIONS IN HIGH-ENERGY PHYSICS EXPERIMENTS. • .By MAG. 1980. Published in *Pisa 1980, Proceedings, Miniaturization • Of High Energy Physics Detectors*, 25-39. • SEMICONDUCTOR DETECTORS FOR LIFETIME MEASUREMENTS AND HIGH SPACE RESOLUTION. • By G.Bellini,L.Foa,M.A.G 1982. 30pp. Phys.Rept.83:9-38,1982 • MICRODETECTORS FOR HIGH-ENERGY PHYSICS. .By M.A.G.,. 1981. In *Villars-sur-ollon 1981, Proceedings, General Meeting On Lep*, 179-211 • Boosting system • First idea of an asymmetric B Factory to • boost the B0B0 system and allow the time • measurement in 1989 • AN ASYMMETRIC B FACTORY BASED ON PEP. • By PP.Oddone,. Feb 1989. In*Santa Monica 1989, The fourth family of quarks and leptons* 237-247 • B-FACTORIES: A PERSONAL OVERVIEW.By P.Oddone 1989. In *Blois 1989, CP violation and beauty factories and related issues in physics* 299-304. Marcello A Giorgi

  9. Asymmetric Bfactories PEPII and KEKB e- (8GeV) e+(3.5Gev) e- (9GeV) e+(3Gev) Marcello A Giorgi

  10. BaBar Detector EMC 6580 CsI(Tl) crystals e+ (3.1GeV) 1.5T solenoid DIRC (PID) 144 quartz bars 11000 PMs Drift Chamber 40 stereo layers e- (9GeV) Silicon Vertex Tracker 5 layers, double sided strips Instrumented Flux Return iron / RPCs (muon / neutral hadrons) • SVT: vertexing and tracking: crucial for t and low pT tracks • DCH: main tracking device, also dE/dx for particle ID • DIRC: K- separation > 3.4 for P < 3.5GeV/c • EMC: very good energy resolution; electron ID,  and  reco. • IFR: Muon and neutral hadrons (K0L) ID Marcello A Giorgi

  11. 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

  12. Exclusive B decay reconstruction • Particle ID Typical reconstruction efficiency 15-40% Purity: 97% for J/K0s ; lower for: Charmless hadronic B decays: Marcello A Giorgi

  13. B Flavour Tagging Tag Performance: and Full Tagging algorithm combines all in Neural Network, Tag categories based on particle content and NN output. CP asymmetry QT=30.5% (6 tag categories) , it was 28%(4 categories) in 2002 analysis t resolution dominated by tag side: 1 ps  170 m t dependences and resolutions perfect resolution smeared resolution B  1.6 ps  250 m Marcello A Giorgi

  14. sin2 from mixing & bccs “tree” amplitudes a g β K0 mixing B0 decay B0 mixing c b s d b d c W- s s b d d d d * * Vud Vub Vtd Vtb • all decay amplitudes (tree and penguin) have same weak phase: • no direct CP violation, no CP violation in mixing expected Clean! * Vcd Vcb • BF((ll)KS()) = 3.5  10-4 (“large”) • Selection: purity 97% • Similarly: c1KS, (2s)KS , … Marcello A Giorgi

  15. 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

  16. 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

  17. 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

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

  19. 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 A.Bozek, CP-4 hep-ex/0406067 Marcello A Giorgi

  20. 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

  21. 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

  22. From aeff to a Gronau-London method (isospin triangles): BF of If BF (00) is small then the Grossman-Quinn bound can be applied: Marcello A Giorgi

  23. 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

  24. 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

  25. 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

  26. 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 C.Dallapiccola, CP-6 Marcello A Giorgi

  27. 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

  28. 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] BABAR CONF-04/038 hep-ex/0408003 M.Cristinziani, CP-5; A.Somov, CP-6 Marcello A Giorgi

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

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

  31. Do and yield the same sin2b ? Beyond the Standard Model? Marcello A Giorgi

  32. 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! Purely dimensional estimate A.Hoecker ICHEP04 Note that within QCD these uncertainties turn out to be smaller ! New phases from SUSY? Marcello A Giorgi

  33. 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

  34. 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

  35. 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

  36. 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

  37. Results on sin2b from s-penguin modes 3.5s All new! All new! 2.7s from s-penguin to sin2b (cc) 2.4s from s-penguin to sin2b (cc) Marcello A Giorgi

  38. 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

  39. 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

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