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CP Violation and CKM Angles Status and Prospects

CP Violation and CKM Angles Status and Prospects. Klaus Honscheid Ohio State University C2CR 2007. Two asymmetric-energy B factories. 13 countries, 57 institutes, ~400 collaborators. The Two Asymmetric Energy B Factories. PEP-II at SLAC. 9 GeV (e - )  3.1 GeV (e + )

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CP Violation and CKM Angles Status and Prospects

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  1. CP Violation and CKM AnglesStatus and Prospects Klaus Honscheid Ohio State University C2CR 2007

  2. Two asymmetric-energy B factories 13 countries, 57 institutes, ~400 collaborators The Two Asymmetric Energy B Factories PEP-II at SLAC 9 GeV (e-)  3.1 GeV (e+) peak luminosity: 1.21034cm-2s-1 Belle BaBar KEKB at KEK 8 GeV (e-)  3.5 GeV (e+) peak luminosity: 1.71034cm-2s-1 11 nations, 77 institutes, ~600 persons K. Honscheid, Ohio State University, C2CR 2007

  3. Experimental Landscape (early 2007) Tevatron > 2.4 fb-1 # of B decays recorded 1.3 Billion 0.8 Billion Belle 710 fb-1 400 fb-1 BaBar Total Integrated Luminosity (fb-1) CLEO II.5 CLEO II K. Honscheid, Ohio State University, C2CR 2007

  4. CP Violation in the Standard Model CP Operator: coupling q’ q’ g g* CP( ) = q q J J Mirror To incorporate CP violation g ≠ g* (coupling has to be complex) K. Honscheid, Ohio State University, C2CR 2007

  5. CP Violation in the SM: The CKM Matrix • The CKM matrix Vij is unitary with 4 independent fundamental parameters • Unitarity constraint from 1st and 3rd columns: i V*i3Vi1=0 d s b u Vud Vus Vub Vcd Vcs Vcb Vtd Vts Vtb c t CKM phases (in Wolfenstein convention) a = p-g-b g ~ arg[Vub*] b ~ arg[Vtd*] K. Honscheid, Ohio State University, C2CR 2007

  6. Interfering Amplitudes in Bo Kp Decays Penguin decay Tree decay g G(B) – G(B) G(B) + G(B) A2 = a2e-if2 eid2 A1 = a1e-if1 eid1 |A|2 – |A|2 |A|2 + |A|2 Interference(A1+A2)2≠ (A1+A2)2 A1 = a1eif1 eid1 B0K-p+ + A2 = a2eif2 eid2 B0K+p- + ~ 2sin(f1 - f2) sin(d1 - d2) = 0 Asymmetry = = K. Honscheid, Ohio State University, C2CR 2007

  7. CP Violation in Bo Kp Decays BABAR background subtracted 227 x 106 B0 Mesons CountB0K+Decays 227 x 106 B0 Mesons CountB0K-+Decays Is N(B0K+) equal to N(B0K-+)? K. Honscheid, Ohio State University, C2CR 2007

  8. Mixing Induced CP violation B0 J/yKs ei0 B0 ei2b + Two Amplitudes Interference ACP ~ sin2b Golden mode B0J/yKs:CP eigenstate, high rate, theoretically clean No weak phase ei0 Two Vtd vertices ei2b K. Honscheid, Ohio State University, C2CR 2007

  9. A Complication: Quantum Coherence t =0 Dz = Dt gbc bg =0.56 l - (e-, m -) The two mesons oscillate coherently : at any given time, if one is a B0 the other is necessarily a B0 Dt picoseconds later, the B 0 (or perhaps its now a B 0) decays. In this example, the tag-side meson decays first. It decays semi-leptonically and the charge of the lepton gives the flavour of the tag-side meson : l -= B 0l+ = B 0. Kaon tags also used. (4S) We need to know the flavor of the B at a reference t=0 Flavor Tagging and measure the difference in decay time Dt Time Dependence At t=0 we know this meson is B0 B 0 rec B 0 B 0 tag Time dependent asymmetry ACP = SCPsin(DmDt)  CCPcos(DmDt) SCP = fCPsin2b (fCP= ±1), CCP “direct” CP violation = 0 forJ/yK K. Honscheid, Ohio State University, C2CR 2007

  10. CP Violation in B0J/yKs PRL 98, 031802 (2007) BaBar preliminary, hep-ex/0607107 Belle preliminary, hep-ex/0608039 B0J/yKL B0J/yKS Dt for B0 tag  B0J/yK Dt for B0 tag  B0J/yK Background Dt asymmetry J/yKLis fCP= +1 J/yKS is fCP= 1 Belle Preliminary Belle Preliminary B0 tags B0 tags B0 tags B0 tags Dt oscillation Period = B mixing Dm Amplitude = D sin2b (Dilution D due to mistags; measured experimentally) K. Honscheid, Ohio State University, C2CR 2007

  11. Sin(2b) World Average Statistics limited Consistent with zero: no evidence for NP in tree decay Heavy Flavors Averaging Group E.Barberio et al., hep-ex/0603003 b = 21.2o± 1.0o Extracting b from sin2b has ambiguities; removed by J/yK*, D*D*KS and Dp0/h/h'/w analyses K. Honscheid, Ohio State University, C2CR 2007

  12. Is “b” Universal? News Flash hep/ex 0702031 Possible contribution from New Physics (NP): new heavy particles in the loop See the following talk by Tom Browder BD+D- S = -1.12 ± 0.37 ± 0.09 A = 0.91 ± 0.23 ± 0.06 (= -C) (expected to be close to 0) Can use 3 different categories of B0 decays to measure b: golden mode K. Honscheid, Ohio State University, C2CR 2007

  13. Let’s try this for the next angle: a Tree decay B0B0mixing Penguin decay  Access to a from the interference of a b→u decay (g) with B0B0 mixing (b) g Inc. penguin contribution How can we obtain α from αeff ? Time-dep. asymmetry : NB : T = "tree" amplitude P = "penguin" amplitude K. Honscheid, Ohio State University, C2CR 2007

  14. How to estimate |a-aeff| : Isospin analysis • Use SU(2) to relate decay rates of different hh final states (h  {p,r}) • Need to measure several related B.F.s 2|-eff| Limiting factor in analysis Gronau, London : PRL65, 3381 (1990) K. Honscheid, Ohio State University, C2CR 2007

  15. Measuring a in Bpp hep-ex/0608035 hep-ex/0607106 +-  ±0 1464±65  0 0 Da Sp+p- = -0.61 ± 0.1 ± 0.04 Ap+p- (=-C) = 0.55 ± 0.08 ± 0.05 BRp+p- = (5.1±0.2±0.2) x 10-6 |Da|<41°@90% C.L. K. Honscheid, Ohio State University, C2CR 2007

  16. Sometimes you have to be lucky hep-ex/0607092 hep-ex/0607097 hep-ex/0607098 • B  rr is almost completely polarized • B r0r0 is small better constraint on Da B0r+r- B+r+r0 B0r0r0 615±57 390±49 K. Honscheid, Ohio State University, C2CR 2007

  17. Combining all methods: a Other solutions disfavoured CL=0.683 Combined:a = [93+119] Global fit without a: aGlobalFit = [ 98+5-19] º K. Honscheid, Ohio State University, C2CR 2007

  18. g = arg[Vub*]: CP violation in DK modes GLW: Gronau, London, Wyler (2001) ADS: Atwood, Dunietz, Soni (1997) GGSZ: Giri, Grossman, Soffer, Zupan (2003) E.g. B+D0 /D0K+ D decays do not involve Vub or Vtd: no contribution to phase ei0 ei0 D0K+ D0/D0 CP state (GLW) D0/D0Kp+/K+p, CA/DCS (ADS) D0/D0KSp+p, Dalitz(GGSZ) B+ V*ub vertex eig D0K+ eig ei0 Relative phase =eig B±  DK: no time dependence; extractgfrom rates and CP asymmetriesbut b  u amplitude is small (for example rB (DK−) = 0.16 ± 0.05 ± 0.01 ± 0.05 Belle) K. Honscheid, Ohio State University, C2CR 2007

  19. The GGSZ method – an example Look for deviations in B±D0K±plots Map out Dalitz plot from all D0 Ksp+p- decays B+ B Belle Belle BaBar preliminary; hep-ex/0607104 Belle; Phys.Rev.D 73, 172009 (2006) K. Honscheid, Ohio State University, C2CR 2007

  20. Combined Result for g Combined: g = [62+3824 ] Indirect (CKM) g = [59+94] K. Honscheid, Ohio State University, C2CR 2007

  21. The CKM Model has passed the experimental test [93 +11-9]o a g b (0,0) [62+38-24]o [21.2 ± 1.0]o New Targets • Effects of TeV new physics  deviations from SM • LFV and new source of CPV • Hidden flavor symmetry and its breaking K. Honscheid, Ohio State University, C2CR 2007

  22. The next few years (2007 – 2010) Belle and BaBar 1 ab-1 (2006) 2 ab-1 (2008) Tevatron 2 fb-1 (2006) 8 fb-1 (2009) LHCb is nearing completion ICHEP08 K. Honscheid, Ohio State University, C2CR 2007

  23. LHCb Prospects (Some of the things they can do) • Bs Mixing phase (s) using BsJ/ • Signal yield: 130k events per L=2fb-1 with a B/S0.1, Sensitivity s ~ 0.021 • Sensitive probe of New Physics effects in the Bs mixing • s = s(SM) + s(NP) with s(SM)=-2l2h ~ -0.037±0.002 V. Vagnoni CKM2006 LHCb atL=2fb-1 now now pre-LHCb LHCb at L=10fb-1 s(s) pre-LHCb LHCb at L=10fb-1 LHCb atL=2fb-1 year year • Sensitivity to g • Standard methods • Golden Mode Bs DsK • Sensitivity ~ 4.2o with 2 fb-1 now s(s) s(g) [o] pre-LHCb with LHCbat L=2fb-1 with LHCb at L=10fb-1 year K. Honscheid, Ohio State University, C2CR 2007

  24. From B-Factories to LHCb – without new physics 2014 Summer 2006 2008* LHCb L=10 fb-1 K. Honscheid, Ohio State University, C2CR 2007

  25. Super B-Factory Plans at KEK and Frascati ILC ring ILC FF IP Design Luminosity ~ 1 x 1036 /cm2/secSynergy with ILCRecycle components (PEP, BaBar)Lots of R&D needed New Beam pipe More RF power Interaction Region Crab crossing q=30mrad. by*=3mm New QCS Damping ring Linac upgrade L = 81035/cm2 /sec Frascati KEK K. Honscheid, Ohio State University, C2CR 2007

  26. Summary • CKM Model is now a tested theory • Great success for theorist • Great success for experimentalist • Great success for the Standard Model a = (93+11-9)o b = (21.2 ± 1.0)o g = (62+38-24)o • Search for Deviations from SM and New Physics • Near Term Future Looks Promising • B Factories only half way done • Tevatron will triple data sample • LHC(b) turn on • Long Term Prospects • LHC(b) upgrades • Super B Factories (KEK, INFN) K. Honscheid, Ohio State University, C2CR 2007

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