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CP Violation Measurements at B Factories – present and future –

Present CKM angles New CP -violating phase Future: Super e + e - B factories. CP Violation Measurements at B Factories – present and future –. Masashi Hazumi (KEK) June 22, 2004 SUSY04, Tsukuba, Japan.

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CP Violation Measurements at B Factories – present and future –

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  1. Present • CKM angles • New CP-violating phase • Future: • Super e+e- B factories CP Violation Measurements at B Factories – present and future – Masashi Hazumi (KEK) June 22, 2004 SUSY04, Tsukuba, Japan

  2. Time-dependent CP violation“double-slit experiment” with particles and antiparticles J/ b b b KS d d d c c s + KS t c c t J/ d d s Quantum interference between two diagrams (Bigi-Carter-Sanda 1981)  Large O(1) CP violation  Very small hadronic uncertainty (~1% or less) ! SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  3. Time-dependent CP violation“double-slit experiment” with particles and antiparticles (Bigi-Carter-Sanda 1981)  Large O(1) CP violation  Very small hadronic uncertainty (~1% or less) ! CP SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  4. Measurement Principle • high-luminosity e+e collider with asymmetric beam energy (~108B mesons) • precise position measurement of B-meson decay vertices (Dz resolution~100mm) seemingly a crazy idea in 1980s  2 B factories (KEK, SLAC) in operation since 1999 (9.1/3.0 GeV at PEPII/BaBar) e-: 8.0 GeV e+: 3.5 GeV BCP e- e+ CP eigenstate ¡(4S) bg ~ 0.425 DzcbgtB ~ 200 mm Btag 10.58GeV/c2 D z ＝ D t Flavor tag Dz c bg O(1)ps SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  5. History ofLuminosity Frontier SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  6. f1: Time-dependent CP violation in B0gJ/Ks etc. SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  7. sin2f1 history 7% precision sin2f1 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  8. B factories studying top quarks Top-quark physics Direct production, Mass, width etc.  CDF/D0 Off-diagonal couplings, phase  BaBar/Belle SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  9. Unitarity Triangle determination at BaBar & Belle _ BB mixing (Dmd) _ _ (r, h) B0gp+p B0grp b g uln with several approaches (excl. & incl.) B0grr f2(a) Bg D(Kspp)K Bg DCPK f3(g) f1(b) (0,1) Bg D(*)p (0,0) B0g J/KS(L), (2S) KS, c1 KS, hc KS B g D(*)ln SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  10. Decay rate with direct CP violation C A is also used B0gp+p:direct CP violation may be large (S, A) = (0.8, 0.0) + (S, A) = (0.8, 0.6) SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  11. B0gp+p- : Significance of CP violation 1) Observation of CP violation (5.2s) App 2) Evidence for direct CP violation 3.2s for App=0 and any Spp Spp 140fb1 Feldman-Cousins Analysis hep-ex/0401029, accepted by PRL SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  12. Constraint on f2 and d CL=0.683 (1s) CL=0.955 (2s) f2 (deg.) CL=0.9973 (3s) d (deg.) Belle 140fb1 |P/T| = 0.45 (more stringent bound for |P/T|<0.45) 95.5% C.L. volume f2 (deg.) d (deg.) |P|/(|T|+|P|) 90 ≤ f2≤ 146 (95.5% CL) sin2f1 = 0.736 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  13. B0gr+r- Preliminary • Larger branching fraction than p+p- • (30  4  5)  10-6 • Small penguin pollution • 3 helicity states • mixture of CP even and odd • Longitudinal fraction = 0.990.03 Slong = -0.19  0.33  0.11 Clong = -0.23  0.24  0.14 • Constraints on a with isospin analysis • interference, non-resonant contributions, I=1 amplitudes neglected • Main systematics: CPV in B backgrounds 2s region for a SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  14. f3with a new method r r Giri, Grossman, Soffer, Zupan, PRD68, 054018 (2003) Dalitz analysis with BD0[Ksp+p-] K A2 interference A1 Ksp+p- Ksp+p- B+: |A2| |A1| r = B-: CPV: Asymmetry in Dalitz dist.: m+=m(Ksp+), m-=m(Ksp-) SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  15. Dalitz analysis with BgD(g Ksp+p-) K(*) BgDK 73 events 73 events B- B+ M2(Ksp+) [GeV2 ] M2(Ksp-) [GeV2 ] Fit to Dalitz distr. obtain f3, d, r K*+ K*- B+ D0K+& D*0K+combined M2(Ksp+) [GeV2 ] M2(Ksp-) [GeV2 ] Preliminary φ3=77(stat)13(syst) 11(model) [26 <φ3 < 126(95.5% CL)] +17 -19 Most powerful method now !! BgDK SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  16. Constraints on Unitarity Triangle f3=95%CL f3=95%CL f2 _ r SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  17. One phase to rule them all .. ? • Beautiful agreements so far! • Triumph of Kobayashi-Maskawa model of CP violation • More precise measurements needed for f2, f3 • At least 1ab-1 to do first precise measurements • Difficulty in Baryogenesis • Many CP-violating phases in physics beyond the SM • Present constraints mainly with transitions between • 3rd 1st generations • 2nd 1st generations b  s (3rd 2nd ) should be explored ! SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  18. Search for a new CP-violating phase SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  19. _Hint of new physics ?: CPV in bgsss virtual particle (top quark, and more ?) CP violation “same” as J/Ks within the Standard Model Penguin~O(l2), Tree~O(l4) deviation = O(1)% Estimations on hadronic uncertainties Grossman, Isidori, Worah, PRD58, 057504 (1998) London, Soni, PLB407, 61 (1997) Grossman, Ligeti, Nir, Quinn, PRD68, 015004 (2003) Gronau, Grossman, Rosner, PLB579, 331 (2004) (not a complete list, sorry !) Penguin diagram Breakthrough to New Physics with loop (penguin) diagrams SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  20. More b g s penguin anomalies G0 G 1 m2 = 1-O( ) • Polarization in BgVV decays • Relations among BgKp branching fractions • Talk by A. Buras • Large Bgh’Xs branching fraction 0.43±0.10 (Belle, fK*0) 0.65±0.07 (BaBar, fK*0) 0.46±0.12 (BaBar, fK*+) 0.95±0.11 (Belle, r+r0) 0.96±0.16 (BaBar, r0K*+) 0.97±0.08 (BaBar, r+r0) ≠ = SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  21. B0gfKs, K+K-Ks, h’Ks [PRL 91, 261602 (2003)] Fit sin2f1 B0 fKS B0K+K-KS B0h’KS “sin2f1” 3.5saway from SM ! SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  22. B0gh’Ks, K+K-Ks, f0Ks, B0gh’Ks (81fb-1) [PRL91, 161801 (2003)] Sh’Ks = +0.02  0.34  0.03 Ch’Ks = +0.10  0.22  0.04 B0g K+K-Ks [hep-ex/0406005] Preliminary SKKKs = -0.56  0.25  0.04 CKKKs = -0.10  0.19  0.10 CP-even fraction =0.980.15 0.04 B0g f0(980)[gp+p-]Ks [hep-ex/0406040] +0.56 -0.51 Sf0Ks = -1.62  0.09  0.04 Cf0Ks = +0.27  0.36  0.10 0.07 Preliminary 3rd error from quasi two-body approximation SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  23. B0gfKS and fKL Preliminary Signal yields are for all regions, histograms are for signal-enhanced regions. +0.08 -0.06 SfK0 = +0.47  0.34 CfK0 = -0.10  0.33  0.10 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  24. Vertexing for B0g Ksp0, Ksp0g Reconstruct B  Ksp0(g) vertex using Ks trajectory and boost trajectory p+ p- boosted U(4s) Ks e+ e- p0 Dz SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  25. B decay vertex with Ks 113fb-1 Preliminary B0g Ksp0 [hep-ex/0403001] +0.38 -0.47 SKsp0 = +0.48  0.06 CKsp0 = +0.40  0.09 +0.27 -0.38 Preliminary B0g K*0(g Ksp0) g [hep-ex/0405082] 105  14 events (68% w/ vtx) SK*0g = +0.25  0.63  0.14 CK*0g = -0.56  0.32  0.09 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  26. b g s vs. b g c “SM” precision meas. fK0: Av = -0.14±0.33 (2.6s away from SM) PDG2004 [Belle/Babar 2.3s away] All bs (2.4s away from SM) SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  27. SfKs history New results coming soon ! Stay tuned. ? BaBar Standard Model Belle SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  28. Integrated luminosity now KEKB/Belle > 100 fb-1 this year (~6 months) ! PEPII/BaBar SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  29. Integrated luminosity in the near future • April 2004: 2.3A x 1.4 A by*=11 mm 1555 bunches L=8.4E33 • July 2004: 2.5A x 1.6 A by*=10 mm 1600 bunches L=10E33 • June 2005: 3.3A x 1.8 A by*=9 mm 1700 bunches L=15E33 • July 2006: 3.9A x 2.0 A by*=8 mm 1715 bunches L=20E33 • July 2007: 4.5A x 2.2 A by*=8 mm 1715 bunches L=24E33 • With good integration reliability and trickle injection: • 100 fb-1 more integrated by Summer 2004. • 500 fb-1 total integrated by Fall 2006. • About 1.0 to 1.3 ab-1 integrated by Fall 2009. Oide’s scenario for KEKB Seeman’s scenario for PEPII SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  30. Super e+e-B factories SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  31. Major upgrade plans KEK SLAC http://belle.kek.jp/superb/loi/ physics part to be submitted to hep-ex soon SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  32. Present situation: lucky for Super B factory ! • We know that • Standard Model (incl. Kobayashi-Maskawa mechanism) is the effective low energy description of Nature. • However most likely New Physics lies in O(1) TeV region. • LHC will start within a few years and (hopefully) discover new elementary particles. • Flavor-Changing-Neutral-Currents (FCNC) suppressed • New Physics w/o suppression mechanism excluded up to 103 TeV.  New Physics Flavor Problem • Different mechanism  different flavor structure in B decays (tau, charm as well) Comprehensive studies of B decays with the luminosity upgrade will be quite effective and essential. SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  33. B0g (cc)Ks vs. fKs 6811 signals L=5 1035 cm-2s-1 1999-2003 data set (158fb-1) in 1 week 2716 signals SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  34. One Snowmass year operation (5 ab-1) SuperKEKB LoI J/Ks fKs S[fKs]input = +0.24 DS-Sf – SJ/Ks [~ O(l2) in SM] SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  35. 3-body CPeigenstates T. Gershon and M. Hazumi, hep-ph/0402097 • Any final state with 3 spin-0 CP-eigenstate neutral particles is a CP eigenstate. • Many modes are available. • B0g KsKsKs most promising • branching ratio already observed (Belle 78fb-1) • Pure b g sss • Small background SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  36. BgffK: ultra-clean mode • Interference between B ghc(gff)K and 3-body b g s process • CP violation in the SM ~0, can be ~0.4 if new physics enters b g s • Ultra-clean mode to reconstruct, almost no background M. Hazumi, PLB583, 285 (2004) Belle 78 fb-1 (7 events) PRL91, 241802 (2003) Sensitivity to new phase: ffK vs. fKs SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  37. Distinguish different new physics models ! T. Goto, Y.Okada, Y.Shimizu,T.Shindou, M.Tanaka, hep-ph/0306093 + SuperKEKB LoI Different SUSY breaking scenarios can be distinguished ! SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  38. More tests of SUSY breaking scenarios SuperKEKB LoI • S(fKs) • S(K*g) • Br(b g sg) • A(b g sg) • AFB(b g sll) • Br( tgmg) 50ab-1 “DNA identification” of new physics SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  39. CKM Unitarity Triangle (in)consistency Two cases at 5 ab-1 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  40. CKM Unitarity Triangle (in)consistency Two cases at 50 ab-1 SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  41. “B-meson beam” with full reconstruction Unique at U(4S) Need large statistics • Interesting decays • B → uln • B → tn, Knn • B → Dtn • etc B e- (8GeV) e+(3.5Gev) Υ(4S) p B full tagging • B → Dtn G(BgDtn)/G(BgDmn) at B factory with 50 ab-1 0.2~1% for B+ (efficiency depends on purity). SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  42. Summary of physics reach SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  43. Summary of B physics at present • BaBar/PEPII and Belle/KEKB doing extremely good • sin2f1 now measured with 7% accuracy • CP violatioin in B0gp+p- observed • First constraint on f3 • Tantalizing hint of new physics in b g s CP asymmetries … and many more new observations for tomorrow ! (recall it is just a few years from the first obs. of B0gf Ks New ideas for measurements proposed constantly ! SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  44. Summary for the future B physics • ~1ab-1 by ~2007: Exciting time will continue ! • f2, f3 measurements  first precise tests of the triangle • Observation of direct CP violation (B0gp+p-, K+p-, etc.) • (with luck) Observation of a new CP-violating phase • Super B factory in the LHC era • play a key role to elucidate the new physics flavor problem. • LHC results will serve as important inputs (similar to Tevatron) SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  45. SUSY2014 ? Yankee Stadium SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  46. Backup Slides SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  47. Measurement Principle ~1 ps SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  48. CP violation in B0gp+p- 140fb1 App = +0.58 0.15(stat) 0.07(syst) Spp = 1.00 0.21(stat) 0.07(syst) 0.86 < LR 1.0 hep-ex/0401029, accepted by PRL SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

  49. B0gp+p- : Significance of CP violation 1) Observation of CP violation (5.2s) 2) Evidence for direct CP violation 3.2s for App=0 and any Spp App 3.3s for “superweak” case Spp Belle 140fb1 Feldman-Cousins Analysis SUSY04, Tsukuba, Japan Masashi Hazumi (KEK)

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