B physics results from the Tevatron mixing and CP violation

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1 phyic reult from the Tevatron mixing and CP violation for the CDF and DØD collaboration Moriond EW 2009 La Thuile, Italy 1

2 Introduction Mixing meaurement M (DØ & CDF) Semileptonic aymmetry A l Mixing interference meaurement Γ, φ (DØ & CDF) Direct CP violation meaurement Kπ D 0 K Outline (CDF) (CDF) ± J/ψK ± (π ± ) (DØ) Summary & Outlook (DØ & CDF) Mixing and CP Violation Reult from Tevatron Tevatron i a unique place to tudy meon in thi talk I will cover motly reult 2

3 The CDF & DØ Detector Excellent tracking & ma reolution Silicon η < 2, 90 cm long 96 layer drift chamber 44 to 132 cm Triggered Muon coverage p T > 1.5 GeV, η < 1 Low p T Muon identification p T > 1.5 GeV, η < 2 High tracking efficiency: 95% η < 3 (Silicon dik) 3 Mixing and CP Violation Reult from Tevatron

4 Mixing b b Schrödinger Equation: M 12 tem from the real part of the box diagram, dominated by top Γ 12 tem from the imaginary part, dominated by charm Diagonalization give two phyically oberved Light and Heavy ma eigentate CP even CP odd q for = 1 p i.e. no CP violation with p 2 q 2 = 1 quahed triangle flat triangle 4 Mixing and CP Violation Reult from Tevatron

5 Γ & φ from J/ψ φ Golden decay mode, equivalent to d J/ψK for in(2β) meaurement Flavor mixing CPV angle φ 12 = arg( M 12 / Γ12 ) very mall in SM ( 0.004) 12 CPV phae, φ * * = arg( V V / V V ) for J/ψφ i alo mall in SM ( 0.04) t tb c cb New phyic contribution are ame to both the quantitie Significant large meaurement of φ i a unambiguou ign of NP Angular analyi in tranverity bai Different ditribution in the time-angular pace for and Unbinned maximum likelihood fit to ma, lifetime and decay angle Weight applied to the angular ditribution of and according to tagging probability (p), whenever available, otherwie p = 0.5 Two fold ambiguity due to angular ditribution equation, can be removed for fixed trong phae. 5 Mixing and CP Violation Reult from Tevetron

6 Γ & φ from DØ 90% CL 68% CL (trong phae contrained) φ = ( tat ) 0.02 ( yt ) rad Γ = 0.19 ± 0.07 ( tat ) ( yt ) p ± 65 τ = 1.52 ± 0.05( tat) ± 0.01( yt) PRL 101, (2008) p Mixing and CP Violation Reult from Tevetron Probability of SM = 6.6% ~1.8σ 6

7 Γ & φ from CDF 95% CL 68% CL 3166 ± 56 φ β φ /2 = / 2 = = [0.28,1.29 ] PRL 100, (2008) rad Probability of SM = 7.0% ~1.8σ 7 Mixing and CP Violation Reult from Tevetron

8 Γ & φ from Tevatron Combination of reult, with trong phae free Combination for CDF 1.35 fb -1 & DØ 2.8 fb σ deviation from SM DØ reult combined without trong phae contraint but without yt error (mall compare to tat) 90% CL Region φ Γ [ 2.85, 1.65 ], [ 1.47, 0.29 ] rad [ 0.264, ], [0.036,0.264 ] p 1 8 Mixing and CP Violation Reult from Tevetron

9 Mixing frequency, M The probability of P e = 2 e 2 Γt [coh Γ t 2 Γ t 2 co( Mt )] 1 Γt t / τ mixing i given by P = e ( 1 ± co Mt ) P = [coh co( Mt )] Tagging efficiency Sig = ε D 2 2 Dilution One need three ingredient: flavor at decay flavor at production Good proper decay length reolution S S Signal e 2τ ( M σ For Γ = 0 Proper decay length reolution ackground t ) 2 Tranvere decay length Proper decay length / 2 K lepton hadron jet frag b PV b frag L xy K SV D π 9 Mixing and CP Violation Reult from Tevetron

10 DØ M reult Combined amplitude can Senitivity : 27.3 p -1 Mixing and CP Violation Reult from Tevetron M (p -1 ) A parabolic fit to likelihood can for M return: M = ±0.93 ±0.30 p σ ignificance 10

11 CDF M reult M = ± 0.10 (tat) ± 0.07 (yt) p σ tatitical ignificance 11 Mixing and CP Violation Reult from Tevetron

12 a l in emileptonic decay Ueful quantity called, emileptonic CP aymmetry for decay, it SM expected value i very mall (~2.06±0.57).10-5 Directly related with phyical quantite Im(Γ 12 /M 12 ) = ( Γ / M )tanφ, hence alo ueful in contraining φ meaurement Meaurement of the charge aymmetry uing a time-dependent analyi of D µ ν X, ( D φπ, φ K K ) 0 Charge of the muon give final tate tagging, while initial tate tagging uing tandard flavor tagging method (SSTOSTEvtCharg) Reult: a l = ± ( tat) ( yt) Mot precie direct meaurement to date! µ D DØ Run II Preliminary CDF alo make indirect meaurement of ame quantity uing dimuon charge aymmetry from 1.6 fb-1 a l = ± 0.021( tat) ± 0.018( yt) µ : ± 718 event D 12

13 Direct CP violation Charmle decay proceed though b u CKM uppreed tree diagram and b {,d} loop diagram Similar amplitude and their interference it may lead to izable direct CPV New particle in loop diagram can change the SM expectation value For ± f ± decay, direct CP violation can be aociated to non-zero charge aymmetry A ch = Γ( Γ( ) Γ( ) Γ( For neutral decay to charge particle, a imilar charge aymmetry i defined baed on aociated particle charge with K/π, in decay f f f f ) ) 13 Mixing and CP Violation Reult from Tevetron

14 CP violation in Kπ Direct CPV for Kπ decay i defined a A CP = N( N( 0 0 K K π ) π ) N ( N ( π ) π ) Uing impact parameter diplaced track trigger data 0 Kπ, 0 ππ, KK, Kπ and Λ b pk/π decay are inlcuded 0 0 K K Unbinned maximum likelihood fit i performed uing kinematic and PID, where PID for each track i defined a PID = de / dx de / dx ] mea de / dx ] π ] de / dx ] π K Reult: 0 ACP ( K π ) = 0.39 ± 0.15( tat) ± 0.08( yt) 1 t Meaurement of Direct CPV from Kπ decay, 2.5σ away from 0 Compatible with expected value of ~0.37, H.J.Lipkin, PL 6212, 126, 2005 ACP from 0 Kπ i in agreement with -factorie reult. 14

15 CP violation in D 0 K Direct CPV for D 0 K decay i defined a A CP = R( R( D D 0 0 K K ) R( ) R( D D 0 0 K K D 0 i CP-even, i.e. either from KK or ππ Unbinned maximum likelihood fit i performed uing invariant ma, kinematic and PID ) ) Reult: 0 A CP ( D K ) = 0.39 ± 0.17( tat) ± 0.04( yt) In agreement with the other meaurement 15

16 CP violation in ± J/ψK ± (π ± ) Charge aymmetry in ± J/ψ K ± (π ± ) decay A CP N( = N ( J / ψk J / ψk ( π )) N ( ( π )) N( J / ψk J / ψk ( π )) ( π )) Recontructed event include J/ψK, J/ψπ, J/ψK* and combinatorial background (KG) Fit aign, ~40K event due to J/ψK & ~1.6K due to J/ψπ Poible production/detector aymmetrie effect are taken care Reult: A CP ( J / ψk ) = ± ( tat) ± ( yt) A CP ( J / ψπ ) = 0.09 ± 0.08( tat) ± 0.03( yt) SM prediction are ~0.003 for J/ψK (W.-S. Hou, M. Nagahima, A. Soddu, arxiv:hep-ph/ ) ~0.01 for J/ψπ (I. Dunietz, Phy. Lett. 316, 561 (1993)) 16

17 Summary and Outlook Tevatron ha rich program for CP violation tudie, many meaurement are 1 t and mot precie All the analyi preented in thi talk ued data et of up to 2.8 fb -1. We are expecting updated reult with twice a much data. Meaurement of CP violation phae, φ provide direct window for New Phyic earch, updated meaurement and combination will be intereting Search for direct CP violation in ector can alo how new phyic hint with more precie meaurement Tevatron i expected to deliver 6 fb -1 by 2009, more than 4.5 fb -1 i available for analye, more reult oon, tay tuned! 17 Mixing and CP Violation Reult from Tevetron

18 Additional Slide 18

19 Angular Ditribution V1 V2 (J/ψ φ) i.e. Spin 0 11 L= 0,1,2 L = 0 and 2 correpond to CP even; L=1 CP odd Angular ditribution can be written in helicity bai, UT generally Tranverity bai i ued to write angular ditribution, where polar coordinate are defined in J/ψ ret frame and φ ret frame Polarization Amplitude 19

20 Polarization Amplitude hep-ph/ ph/ & hep-ph/ ph/ Upper ign correpond to: Time evolution of pure 0 J/ψ φ at t=0 Lower ign correpond to: Time evolution of pure 0 J/ψ φ at t=0 Γ average decay width of two phyical eigentate δ 1 δ 2 CP-conerving trong phae ; ~ π and 0 A 0 (0), A (0) CP-even linear polarization amplitude at t=0 A (0) CP-odd linear polarization amplitude at t=0 20

21 Contraining trong phae Under flavor SU(3) ymmetry, trong phae and amplitude are expected to be imilar for J/ψφ & d J/ψK* arxiv: v5 [hep-ph], Michael Gronau, Jonathan L. Roner δ 1 and δ 2 have 2-fold ambiguity, the one with co(δ 1 )<0 i difavored theoretically and experimentally, ee hep-ex (p8) The relative trong phae are known to have a two-fold ambiguity when meaured in an angular analyi alone. In contrat with earlier publication [1, 2, 5] we ue here the et of phae predicted by Suzuki [15] uing argument baed on the conervation of the quark helicity in the decay of the b quark. We have confirmed experimentally thi prediction by the tudy of the variation with Kπ invariant ma of the phae deference between the K.(892) amplitude and a non-reonant Kπ S-wave amplitude [3]. [15] M. Suzuki, Large violation of -quark helicity conervation in J/pi K*, Phy. Rev. D 64, (2001). 21 Mixing and CP Violation Reult from Tevetron

22 Amplitude Scan Scan M, for each value find A ± σ A p ± ~ ( 1 ± D co ( M Kt ) A ) If ample frequency i M amplitude A = 1 otherwie A =0 22 Mixing and CP Violation Reult from Tevetron

23 From QCD Weak decay contant ag parameter un Large uncertainty cancel out 23 Mixing and CP Violation Reult from Tevetron