1 / 103

Measurements of f 1 / b and f 2 / a

Measurements of f 1 / b and f 2 / a. July 31, 2006 XXXIII International Conference on High Energy Physics (ICHEP’06). Masashi Hazumi (KEK). Many thanks to many people, in particular to: T. Aushev, T. Browder, P. Chang, R. Faccini, K. George, T. Gershon, K. Hara,

varana
Télécharger la présentation

Measurements of f 1 / b and f 2 / a

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Measurements of f1/b and f2/a July 31, 2006 XXXIII International Conference on High Energy Physics (ICHEP’06) Masashi Hazumi (KEK) Many thanks to many people, in particular to: T. Aushev, T. Browder, P. Chang, R. Faccini, K. George, T. Gershon, K. Hara, H. Ishino, A. Lazzaro, S. Olsen, Y. Sakai, O. Tajima and K. Trabelsi

  2. New ResultsfromBaBarand Belle for Stringent Tests of the Kobayashi-Maskawa Model of CP Violation

  3. Main New Results Covered in This Talk(all results are preliminary) K.George • f1 with tree diagram (b gccs) • BaBar: sin2b in B0g J/K0, (2S)KS, hcKS, c1KS, J/K*0 • Belle: sin2f1in B0g J/K0 • f1 with penguin diagram (bgsqq) • BaBar: B0gK+K-K0, h’K0, KSKSKS, KS, rKS, p0KS • Belle: B0gh’K0 ,p0KS • Belle: B0gfK0, K+K-KS , KSKSKS , f 0KS, KS • f2 • BaBar: pp, rr, rp • Belle: pp • Belle: rp O. Tajima A. Lazzaro K.Hara This talk S. Telnov H. Ishino This talk

  4. Remarks • Some other new results and recently published results also mentioned but very briefly. • g/f3-related  R.Kowalewski (next speaker) • My apologies if your favorites are not included

  5. 25th Anniversary of Time-dependent CP Violation (tCPV)

  6. Tribute from S. Olsen We need millions of B and use them to search for mixing and CP violation Tony, are you nuts? Look at this. This took us six months! 5 B mesons

  7. 13 countries, 57 institutes, ~400 collaborators Two Asymmetric-energy B Factories PEP-II at SLAC 9GeV (e-)  3.1GeV (e+) peak luminosity: 1.121034cm-2s-1 Belle BaBar KEKB at KEK 8GeV (e-)  3.5GeV (e+) peak luminosity: 1.651034cm-2s-1 11 nations, 80 institutes, 623 persons world record

  8. Integrated Luminosity As of July 24, 2006 KEKB + PEP-II KEKB for Belle PEP-II for BaBar

  9. 1000/fb !! • Far beyond the design luminosities of both proposals • Triumph in accelerator science reached on July 13, 2006 ~ 1 Billion BB pairs

  10. Motivation sin2b history (1998-2005) Q. What is the main source of CP violation ? A. Kobayashi-Maskawa phase IS the dominant source ! Paradigm shift ! Q. Are there deviations from the CKM picture ? (e.g. new CP-violating phases) • Two promising approaches • Overconstrain the unitarity triangle: precise measurements of • a and b needed • 2) Compare sin2b in tree diagram and penguin diagram (e.g. b g s)

  11. b/f1

  12. J/ b b b KS d d d c c s KS t t c c J/ s d d Time-dependent CP violation (tCPV)“double-slit experiment” with particles and antiparticles Quantum interference between two diagrams box diagram + tree diagram tree diagram Vtd + Vtd You need to “wait” (i.e. Dt0) to have the box diagram contribution.

  13. tCPV in B0 decays e.g. for J/ Ks S = -CPsin2f1 = +sin2f1 A = 0 to a good approximation (CP : CP eigenvalue) Mixing-induced CPV Direct CPV (A = -C a la BaBar)

  14. B0 tag (OF-SF)/(OF+SF) Mixing of D*ln Good tag region _ _ B0 tag B0 tag |Dt| (ps) -xCPsin2f1 B0 tag S = 0.65 A = 0.00 R : detector resolution w : wrong tag fraction (misidentification of flavor)  (1-2w) quality of flavor tagging They are well determined by using control sample D*ln, D(*)p etc…

  15. b/f1 with trees- Results -

  16. _ O. Tajima B0 J/y K0 : 535 M BB pairs B0 J/y KS 0 B0 J/y KL 0 Nsig = 7482 Purity 97 % CP odd Nsig = 6512 Purity 59 % CP even pKL information is poor  lower purity BELLE-CONF-0647 Belle preliminary

  17. _ B0 tag B0 tag _ B0 tag O. Tajima background subtracted B0 J/y KS 0 B0 J/y KL 0 B0 tag Asym. = -xCPsin2f1sinDmDt BELLE-CONF-0647 sin2f1= +0.643 ±0.038 A = - 0.001 ±0.028 sin2f1= +0.641 ±0.057 A = +0.045 ±0.033 stat error stat error

  18. _ B0 tag B0 tag B0 tag _ _ B0 tag B0 tag B0 J/y K0 : combined result O. Tajima B0 J/y KS 0 B0 J/y KL 0 B0 tag Asym. = -xCPsin2f1sinDmDt BELLE-CONF-0647 sin2f1= +0.643 ±0.038 A = - 0.001 ±0.028 sin2f1= +0.641 ±0.057 A = +0.045 ±0.033 stat error stat error

  19. _ 535 M BB pairs B0 tag New ! _ B0 tag O. Tajima B0 J/y K0 : combined result Preliminary previous measurement sin2f1= 0.652  0.044 (388 M BB pairs) _ sin2f1= 0.642 ±0.031 (stat) ±0.017 (syst) A = 0.018 ±0.021 (stat) ±0.014 (syst) Belle preliminary BELLE-CONF-0647

  20. New ! K.George BaBar2006: sin2b in b g ccs Preliminary A = -0.07  0.028  0.018 • B0g J/K0, • (2S)KS, • hcKS, • c1KS, • J/K*0

  21. 2006: BaBar + Belle Consistency with Vub, f3/g R. Kowalewski (next speaker)

  22. New ! New ! b (not sin2b) measurements Preliminary K.George B0gD*+D*-Ks Time-dependent Dalitz analysis (T.Browder, A. Datta et al. 2000)  cos2b > 0 (94%CL, model-dependent) B0gDh0 (h0 = p0 etc.) Time-dependent Dalitz analysis  cos2b > 0 Belle: 98.3%CL (hep-ex/0605023, accepted by PRL) BaBar 87% CL (BABAR-CONF06/017)

  23. b/f1 with penguins

  24. 3 theoretically-clean modes fKs, h’Ks, 3Ks

  25. Results for 3 theoretically-clean modes fK0, h'K0, KsKsKs

  26. _ 535M BB Belle 2006: B0gfK0 signal Three modes 11417 fKLsignal fgK+K-, KSgp+p- fgK+K-, KSgp0p0 fgKSKL, KSgp+p- 30721 fKS signal B0 momentum New ! (bkg subtracted) B0 mass BELLE-CONF-0647

  27. _ 535M BB New ! Belle 2006: tCPV in B0gfK0 Preliminary “sin2f1” = +0.50  0.21(stat)  0.06(syst) A = +0.07  0.15(stat)  0.05(syst) Dt distribution and asymmetry • Consistent with the SM (~1s lower) • Consistent with Belle 2005 (Belle2005: “sin2f1” = +0.440.270.05) • The most precise measurement now • fKS and fKL combined • background subtracted • good tags • Dt g –Dt for fKL unbinned fit SM BELLE-CONF-0647

  28. Obtain CP parameters for 2-body and 3-body modes simultaneously by time-dependent Dalitz fit _ 347M BB BaBar 2006: tCPV in B0gK+K-K0 K+K-KSgp+p- K+K-KSgp0p0 K+K-KL 151665 K+K-K0signal

  29. BaBar 2006: tCPV in B0gK+K-K0 b measurement (not sin2b) Rejected (within SM) 4.6s fK0: sin2beff = +0.12 ± 0.31(stat) ± 0.10 (syst)

  30. _ 535M BB Belle 2006: B0gh'K0 signal 142146 h'KS signal 45439 h'KL signal B0 momentum B0 mass (bkg subtracted)

  31. _ 535M BB New ! Belle 2006: tCPV in B0gh'K0 Preliminary “sin2f1” = +0.64  0.10(stat)  0.04(syst) A = -0.01  0.07(stat)  0.05(syst) Dt distribution and asymmetry • First observation of tCPV • (5.6s) in a single bgs mode • Consistent with the SM • Consistent with Belle 2005 (Belle 2005: “sin2f1” = +0.620.120.04) • h'KS and h'KL combined • background subtracted • good tags • Dt g –Dt for h'KL BELLE-CONF-0647

  32. _ 347M BB New ! BaBar 2006: tCPV in B0gh'K0 Preliminary “sin2b” = +0.55  0.11(stat)  0.02(syst) A = +0.15  0.07(stat)  0.03(syst) “sin2b” 4.9s from zero. Cf. BaBar 2005: “sin2b” = +0.36  0.13  0.03

  33. _ 535M BB New ! Belle 2006: tCPV in B0gKSKSKS Preliminary “sin2f1” = +0.30  0.32(stat)  0.08(syst) A = +0.31  0.20(stat)  0.07(syst) Dt distribution and asymmetry B0 mass 18517 KSKSKS signal • background subtracted • good tags BELLE-CONF-0647

  34. _ 347M BB New ! BaBar 2006: tCPV in B0gKSKSKS Preliminary “sin2b” = +0.66  0.26(stat)  0.08(syst) A = +0.14  0.22(stat)  0.05(syst) Dt distribution and asymmetry 17617 KSKSKS signal

  35. Results for other b g s modes (~20sec/result)

  36. _ 535M BB New ! Belle 2006: tCPV in B0gf0KS Preliminary “sin2f1” = +0.18 0.23(stat)  0.11(syst) A = -0.15  0.15(stat)  0.07(syst) Raw Asymmetry B0 mass 377  25f0KSsignal p+p- mass good tags BELLE-CONF-0648

  37. _ 347M BB New ! BaBar 2006: tCPV in B0gp0KS Preliminary “sin2b” = +0.33  0.26(stat)  0.04(syst) A = -0.20  0.16(stat)  0.03(syst) 425  28 p0KSsignal

  38. _ 535M BB New ! Belle 2006: tCPV in B0gp0KS Preliminary “sin2f1” = +0.33 0.35(stat)  0.08(syst) A = -0.05  0.14(stat)  0.05(syst) Raw Asymmetry B0 mass 515  32 p0KSsignal good tags BELLE-CONF-0648

  39. _ 535M BB New ! Belle 2006: tCPV in B0gK+K-KS Preliminary “sin2f1” = +0.68 0.15(stat)  0.03(syst) (CP-even) A = -0.09  0.10(stat)  0.05(syst) +0.21 -0.13 Raw Asymmetry B0 mass 840  34 K+K-KSsignal good tags BELLE-CONF-0648

  40. _ 535M BB New ! Belle 2006: tCPV in B0gKS Preliminary “sin2f1” = +0.11 0.46(stat)  0.07(syst) A = -0.09  0.29(stat)  0.06(syst) Raw Asymmetry 118  18 KSsignal good tags B0 mass BELLE-CONF-0648

  41. _ 347M BB New ! BaBar 2006: tCPV in B0gwKS Preliminary “sin2b” = +0.62 (stat)  0.02(syst) A = +0.43 (stat)  0.03(syst) +0.25 -0.30 +0.23 -0.25 142  17p0KSsignal

  42. _ 347M BB BaBar 2006: tCPV in B0gr0KS Preliminary “sin2b” = +0.17  0.52(stat)  0.26(syst) A = -0.64  0.41(stat)  0.25(syst) quasi 2-body approach (restricting to the region dominated by r0) 111  19 r0KSsignal

  43. Smaller than bgccs in all of 9 modes Theory tends to predict positive shifts (originating from phase in Vts) 2006: f1 with bgs Penguins Preliminary Naïve average of all b g s modes sin2beff = 0.52 ± 0.05 2.6 s deviation between penguin and tree (b g s) (b g c) More statistics crucial for mode-by-mode studies

  44. Standard penguin (bird), or something else (rabbit may be) ? More statistics crucial for mode-by-mode studies

  45. Other handles to search for new physicswith penguin diagrams • B0g KsKs (b g d penguin): even higher statistics needed • B gKp sum rule [Gronau, Rosner 2005] • A(K0p0) = A(K+p-) + A(K0p+) –A(K+p0) • B0g Ksp0g (electromagnetic penguin) • New physics may lead to right handed currents. This can be investigated using time-dependent CPV measurements of b g sg decays and will be discussed in Barlow's talk. S ~ 0 expected in SM -0.120.11 -0.160.04

  46. f1 “beam” f2 “banana” a/f2

  47. – – – – – t Vud u b d u b With the tree diagram only d p/r V*ub – Sp+p- = +sin2f2 Ap+p- = 0 B0 B0 t b d p/r B0 d d Mixing diagram Decay diagram (tree) tCPV and f2 (a) f2 VtdV*tb VudV*ub f3 f1 VcdV*cb V*tb Vtd Vtd V*tb 3 possibilities: pp, rr, rp

  48. _ 535M BB New ! H. Ishino Belle 2006: B0→p+p− decay (CP asymmetry) BELLE-CONF-0649 1464±65 signal events p+p− yields first error: stat., second: syst. Large Direct CP violation (5.5s) Large mixing-induced CP violation (5.6s) Preliminary p+p− asymmetry confidence level contour background subtracted

  49. New ! BaBar 2006: tCPV in B0gp+p- S. Telnov Preliminary Evidence for CP violation (3.6s) Direct CP violation not yet observed confidence level contour

  50. History of B0→p+p− decay (C = -A) 2.3s diff. btw. Belle and BaBar

More Related