CP Violation and CKM Angles Status and Prospects Klaus HonscheidOhio State UniversityC2CR 2007

Two asymmetric-energy B factoriesPEP-II at SLACKEKB at KEKBelleBaBar9 GeV (e-) 3.1 GeV (e+)peak luminosity: 1.21034cm-2s-1

8 GeV (e-) 3.5 GeV (e+) peak luminosity: 1.71034cm-2s-1

11 nations, 77 institutes, ~600 personsThe Two Asymmetric Energy B Factories

Experimental Landscape (early 2007)Total Integrated Luminosity (fb-1)CLEO IICLEO II.5BaBarBelle 710 fb-1

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CP Violation in the Standard ModelCP( ) =CP Operator:qqJgqqJg*MirrorcouplingTo incorporate CP violation g g* (coupling has to be complex)

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

CKM phases (in Wolfenstein convention) udtcbsVud Vus Vub

Vcd Vcs Vcb

Vtd Vts Vtb a = p-g-bg ~ arg[Vub*]b ~ arg[Vtd*]

Interfering Amplitudes in Bo Kp DecaysB0 K-p+B0 K+p-A1 = a1 eif1 eid1Asymmetry = = ~ 2 sin(f1 - f2) sin(d1 - d2)= 0A2 = a2 eif2 eid2++

227 x 106 B0 Mesons

Count B0K+ Decays227 x 106 B0 Mesons

Count B0K-+ DecaysIs N(B0K+ ) equal to N(B0K-+ )? CP Violation in Bo Kp Decays

Mixing Induced CP violationGolden mode B0J/yKs:CP eigenstate, high rate, theoretically cleanei0No weak phaseTwo Vtd vertices ei2b

A Complication: Quantum CoherenceWe need to know the flavor of the B at a reference t=0Flavor Tagging and measure the difference in decay time DtTime DependenceB 0 tagB 0 recB 0At t=0 we know this meson is B0Time dependent asymmetry ACP = SCPsin(DmDt) CCPcos(DmDt) SCP = fCP sin2b (fCP= 1), CCP direct CP violation = 0 for J/yK

CP Violation in B0J/yKs Dt for B0 tag B0J/yKDt for B0 tag B0J/yKBackgroundBaBar preliminary, hep-ex/0607107Belle preliminary, hep-ex/0608039B0J/yKSB0J/yKLBellePreliminaryBellePreliminaryB0 tagsB0 tagsB0 tagsB0 tagsDt asymmetryJ/yKL is fCP= +1J/yKS is fCP= 1Dt oscillationPeriod = B mixing DmAmplitude = D sin2b(Dilution D due to mistags; measured experimentally)PRL 98, 031802 (2007)

Sin(2b) World AverageExtracting b from sin2b has ambiguities; removed by J/yK*, D*D*KS and Dp0/h/h'/w analysesHeavy Flavors Averaging GroupE.Barberio et al., hep-ex/0603003b = 21.2o 1.0o

Is b Universal?Can use 3 different categories of B0 decays to measure b:golden mode

Lets try this for the next angle: aAccess to a from the interference of a bu decay (g) with B0B0 mixing (b)Inc. penguin contributionHow can we obtain from eff ?Time-dep. asymmetry :gNB : T = "tree" amplitude P = "penguin" amplitude

How to estimate |a-aeff| : Isospin analysisUse SU(2) to relate decay rates of different hh final states (h {p,r})

Need to measure several related B.F.sGronau, London : PRL65, 3381 (1990)2|-eff|Limiting factor in analysis

Measuring a in B pphep-ex/0607106hep-ex/0608035

Sometimes you have to be lucky6155739049B rr is almost completely polarized

B r0r0 is small better constraint on DaB0 r+r-B+ r+r0B0 r0r0

Combining all methods: aCombined: a = [93+119]CL=0.683Other solutions disfavouredaGlobal Fit = [ 98+5-19] Global fit without a:

g = arg[Vub*]: CP violation in DK modesRelative phase = eigB+D0K+ei0eigV*ub vertex eigE.g. B+D0 /D0K+D0K+D0/D0 CP state (GLW)D0/D0Kp+/K+p, CA/DCS (ADS)D0/D0KSp+p, Dalitz (GGSZ)D decays do not involve Vub or Vtd: no contribution to phaseGLW: Gronau, London, Wyler (2001)ADS: Atwood, Dunietz, Soni (1997)GGSZ: Giri, Grossman, Soffer, Zupan (2003)ei0ei0B DK: no time dependence; extract g from rates and CP asymmetries but b u amplitude is small (for example rB (DK) = 0.16 0.05 0.01 0.05 Belle)

The GGSZ method an exampleBaBar preliminary; hep-ex/0607104Belle; Phys.Rev.D 73, 172009 (2006)BelleBelleMap out Dalitz plot from all D0 Ksp+p- decaysB+BLook for deviations in BD0K plots

Combined Result for gIndirect (CKM) g = [59+94]Combined: g = [62+3824 ]

The CKM Model has passed the experimental testNew TargetsEffects of TeV new physics deviations from SMLFV and new source of CPVHidden flavor symmetry and its breaking [21.2 1.0]o

The next few years (2007 2010)Belle and BaBar1 ab-1 (2006)2 ab-1 (2008)

Tevatron2 fb-1 (2006)8 fb-1 (2009)LHCb is nearing completionICHEP08

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/S0.1, Sensitivity s ~ 0.021Sensitive probe of New Physics effects in the Bs mixings = s(SM) + s(NP) with s(SM)=-2l2h ~ -0.0370.002

nowpre-LHCbLHCb at L=2fb-1LHCb at L=10fb-1years(s)yearnowpre-LHCbLHCb at L=2fb-1LHCb at L=10fb-1s(s)Sensitivity to gStandard methodsGolden Mode Bs DsKSensitivity ~ 4.2o with 2 fb-1s(g) [o]nowpre-LHCbwith LHCb at L=2fb-1with LHCb at L=10fb-1yearV. Vagnoni CKM2006

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Summer 2006From B-Factories to LHCb without new physics2008* LHCb L=10 fb-12014

Super B-Factory Plans at KEK and FrascatiInteraction RegionCrab crossingq=30mrad.by*=3mmNew QCSLinac upgradeMore RF powerDamping ringNew Beam pipeL = 81035/cm2 /secDesign Luminosity ~ 1 x 1036 /cm2/sec Synergy with ILC Recycle components (PEP, BaBar) Lots of R&D neededKEKFrascati

SummaryCKM Model is now a tested theoryGreat success for theoristGreat success for experimentalistGreat success for the Standard Modela = (93+11-9)ob = (21.2 1.0)og = (62+38-24)o

Search for Deviations from SM and New PhysicsNear Term Future Looks PromisingB Factories only half way doneTevatron will triple data sampleLHC(b) turn onLong Term ProspectsLHC(b) upgradesSuper B Factories (KEK, INFN)

Quantum-mechanically, the CP operator converts particles to anti-particles and also the coupling constants become the complex conjugates.no complex phases in strong and em interactions. what about the weak interaction?unitarity4 parameters (3 real, 1 complex phase)many representations. Wolfenstein matches hierarchy shown on previous slideIn this representation the Vtd and Vub the small elements in the corner carry a complex phase.UTwill be our guide for the remainder of the talk.There is an additional slight complication as our B0B0bar pair is in a coherent state Taggingexplain lepton tag. We also use a kaon tag from a subsequent D decay. Combined the tagging efficiency is roughly 30%

now the formalism gets slightly more complicatedthe C term direct CP violation due to the interference of the T and P decays but our sin(2a) term gets also modifiedand the question is how can we obtain a from aeff?not enough data but maybe we can limit a-aeffif A00 is very smalllook for this decay