CLEO CLEO I.5 CLEO II CLEO II.V CLEO III

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1 CLEO CLEO I.5 CLEO II CLEO II.V CLEO III Recent Results on Beauty and Charm Klaus Honscheid Ohio State University SLAC Summer Institute 2000

2 SLAC Summer Institute Klaus Honscheid, Ohio State University (p2)

3 CLEO II (90 95) and CLEO II.V (95-99) SLAC Summer Institute Klaus Honscheid, Ohio State University (p3)

4 CLEO Data Set CESR - symmetric e + e - storage ring operates on Y(4S) BB produced near threshold σ ( BB ) = 1.05 nb 300 MeV/c p B Continuum production σ ( cc) = 1.3 nb σ ( qq) = 2.1 nb Data set CLEO II - 1/3 of the data CLEO II.V - 2/3 of the data Totals ~ 9.1 fb -1 on Y(4S) ~ 4.4 fb -1 off Y(4S) s ~ 1 nb S/N ~ 1/3 SLAC Summer Institute Klaus Honscheid, Ohio State University (p4)

5 B Meson Mass Use fully reconstructed (hadronic) B decays Previous CLEO measurements fit beam constrained mass for B-> D(*)nπ and ψk(*) M bc2 = E 2 beam -p2 and σ (M bc ) ~ σ(e beam ) ~ 2.7 MeV Systematic limited: error on beam energy scale ~ 2 MeV error on initial state radiation correction ~0.5 MeV New result exclusively reconstruct B-> ψ ( ) K do not use beam energy constraint constrain ψ ( ) to PDG values SLAC Summer Institute Klaus Honscheid, Ohio State University (p5)

6 B Meson Mass (2) m(b 0 ) [MeV] = / /- 0.3 m(b + ) [MeV] = / /- 0.4 ( /- 1.8 PDG98) ( /- 1.8 PDG98) (for reference: m B = 0.34+/- 0.32) SLAC Summer Institute Klaus Honscheid, Ohio State University (p6)

7 B Meson Production at the Y(4S) Define? f oo ( Υ(4S) B B ) = = 1.04 ± 0.07 f + ( Υ(4S) B B ) ± +? o o 0.04 Any comparison of B + and B 0 rates depends on f +- /f 00 PDG assumes f +- /f 00 = 1 Theoretical predictions: 0.95 ~ 1.05 Assuming Isospin conservation: Γ(B + -> ψk (*)+ ) = Γ(B 0 -> ψk (*)0 we find f +- /f 00 = / /-0.04 SLAC Summer Institute Klaus Honscheid, Ohio State University (p7)

8 More results on B to Charmonium SLAC Summer Institute Klaus Honscheid, Ohio State University (p8)

9 B to Charmonium branching fractions Decay Mode Signal Background BR (x10-4 ) B 0 -> yk /-0.8+/-0.6 Update K s ->p + p / /-0.8+/-0.7 New K s ->p 0 p / /-2.0+/-0.7 New B 0 -> c c1 K / /-0.4 New B 0 -> yp / /-0.10+/-0.02 New B -> yfk / /-0.13 New B + -> h c K /-2.1 New B 0 -> h c K /-3.3 SLAC Summer Institute Klaus Honscheid, Ohio State University (p9)

10 Search for Direct CP Violation SLAC Summer Institute Klaus Honscheid, Ohio State University (p10)

11 Search for Direct CP Violation SLAC Summer Institute Klaus Honscheid, Ohio State University (p11)

12 Strong Interaction if they get out fast enough... u u b c W u W creates ud pointlike color singlet d But if... Strong Interaction u u u b c Hadronic SLAC Summer Institute Klaus Honscheid, Ohio State University (p12) d W u d Strong Interaction u u b c W n Semileptonic e Understanding Hadronic Decays

13 Hadronic B Decays Semileptonic Decay Hadronic + Factorization A = A = GF V 2 cb V GF V 2 * ub cb V < n g * ub < p m (1 - g 5 ) l >< ( du) 0 >< D D *- ( cb) B ( cb) B * - 0 > 0 > Factorization Tests: Branching Ratios Polarization dg 2 dq G( B fi D ( B fi D * + * + h - ln) ) q 2 = m 2 h = 6p 2 c 2 1 f 2 h V ud 2 Γ L /Γ (B D + h ) = Γ L /Γ (B D + l ν ) q 2=m h 2 SLAC Summer Institute Klaus Honscheid, Ohio State University (p13)

14 SLAC Summer Institute Klaus Honscheid, Ohio State University (p14) (1997)

15 The D* + π + π - π - π o Final State (a) E sidebands σ (b) E around 0 ±2.0σ fit with sideband shape fixed & norm allowed to float Also signals in D o K - π + π o and D o K - π + π + π - (not shown) (D o K - π + ) 358±29 Fit B yield in bins of M(4π) SLAC Summer Institute Klaus Honscheid, Ohio State University (p15)

16 The π + π - π o Mass Distribution What are the decay mechanisms for the (4π) - final state? We examine the π + π π o mass spectrum (2 combinations/event). All 3 D o decay modes summed Enlarged & Dalitz plot exterior removed SLAC Summer Institute Klaus Honscheid, Ohio State University (p16)

17 The ωπ Mass Distribution Fit M B distribution in ωπ mass bins D + ωπ D ωπ Breit-Wigner: Mass = 1432±37 Γ = 376±47MeV All 3 D o decays used Breit-Wigner: Mass = 1367±75 Γ = 439±135MeV only D o K - π + Possible resonance (A) at M=1419±33 MeV, Γ=382±44 MeV SLAC Summer Institute Klaus Honscheid, Ohio State University (p17)

18 D + (ωπ) Angular Distributions For a spin-0 A the D* & ω would be fully polarized Spin 0 χ 2 /dof = 3.5 (cosθ D* ), 22 (cosθ ω ) Ruled out Best fit Γ L /Γ = 0.63±0.09 (D + ), 0.10±0.09 (ω) Spin-0 expectation SLAC Summer Institute Klaus Honscheid, Ohio State University (p18)

19 The Dωπ Final State D ωπ D + ωπ only D o K - π + only D+ K + π - π - 88±14 91±18 Signal: E <2σ (18MeV) Sideband: 3σ< E <7σ No signal in ω sidebands SLAC Summer Institute Klaus Honscheid, Ohio State University (p19)

20 The ωπ Mass Distribution Fit M B distribution in ωπ mass bins Breit-Wigner: Mass = 1415±43 Γ=419±110 MeV Combined D ωπ and D + ωπ modes (179 events) Consistent with D*ωπ result Select ( GeV) for angular study (104 events) SLAC Summer Institute Klaus Honscheid, Ohio State University (p20)

21 The Angular Distributions in B D A : A ω π, ω π π + π between ω in A frame & A boost direction between normal of ω decay plane & ω boost between Α & ω decay planes Small efficiency corrections applied For 1 + and 2, the longitudinal ratio (Γ 1 - preferred, χ 2 /dof (1 - ) = 1.7, (2 + L /Γ) floats ) = 3.2 A - properties: mass = 1418±26±19 MeV, Γ=388±41±32 MeV SLAC Summer Institute Klaus Honscheid, Ohio State University (p21)

22 Identifying the A - with the ρ Clegg & Donnachie: (τ (4π)ν, e + e π + π, π + π + π π ) find two 1 states with (M, Γ)= (1463±25, 311±62) MeV & (1730±30, 400±100) MeV, mixed with non-qq states, only the lighter one decays to ωπ Godfrey & Isgur: Predict first radial excited ρ at 1450 MeV, Γ=320 MeV, B (ρ ωπ )=39% SLAC Summer Institute Klaus Honscheid, Ohio State University (p22)

23 Summary & Discussion of Rates Mode Br (%) # of events B D + π π + π π 1.72±0.14± ±70 B D + ωπ 0.29±0.03± ±15 B D + ωπ 0.28±0.05± ±18 B D π π + π π 1.80±0.24± ±26 B D ωπ 0.45±0.10± ± 6 B D ωπ 0.41±0.07± ±14 ρ dominates the ωπ final state Γ(B D + ρ ) / Γ(B D + ρ ) = 1.04±0.21±0.06 Γ(B D ρ ) / Γ(B D ρ ) = 1.10±0.31±0.06 Γ(B D ρ ) / Γ(B Dρ ) = 1.06±0.17±0.04 Consistent with Heavy Quark Symmetry prediction ( ratio = 1 ) With B (ρ ωπ )=39%, Γ(B D (*) ρ ) ~ Γ(B D (*) ρ ) SLAC Summer Institute Klaus Honscheid, Ohio State University (p23)

24 Testing Factorization Polarization: Γ L /Γ (B D + h ) = Γ L /Γ (B D + l ν ) q 2=m h 2 Branching Fractions: Γ(B D + h ) / dγ/dq 2 (B D + l ν ) q2=mh 2 = 6π 2 c 12 f h2 V ud 2 Using B (ρ ωπ )=39% f ρ = 167 ± 23MeV SLAC Summer Institute Klaus Honscheid, Ohio State University (p24)

25 Extending q 2 : B D*D s * Final State D + D s D + D s D ( )+ D s ** o B(%) 1.10±0.18±0.10± ±0.37±0.24± ±0.78±0.48±0.68 D* + + ρ ρ D S Γ L /Γ (%) 87.8± ± ±13.9±3.6 SLAC Summer Institute Klaus Honscheid, Ohio State University (p25)

26 Charged B Decay and Interference b d W B 0 Decay u c d d b d Decay B 0 ->D - p + B 0 ->D 0 p 0 B + ->D 0 p + Different final states Interference BSW: a 1 a 2 a 1 + z a 2 W Mode B 0 (x10-3 ) B + (x10-3 ) a 1, a 2 are phenomenological constants Dπ 3.0+/ /-0.5 process dependent Dρ 7.9+/ /1.8 Da great success in charm decay: /-3.3 Dρ 2.8+/ /-0.8 destructive interference D*π 2.8+/ /-0.4 smaller G Hadronic for D + D*ρ 6.8+/ /-3.1 t D+ >> t D*a 1 13+/ /-5 D0 D*ρ 2.9+/ /-0.8 SLAC Summer Institute Klaus Honscheid, Ohio State University (p26) c u d d b u W u c d u

27 CKM, rare B Decays and CP Asymmetries V ud V* ub g a V td V tb * b V cd V cb A new measurement of V cb V ub update New rare decays CP Asymmetries SLAC Summer Institute Klaus Honscheid, Ohio State University (p27)

28 A new measurement of V cb B 0 -> D *+ l - ν SLAC Summer Institute Klaus Honscheid, Ohio State University (p28)

29 Results SLAC Summer Institute Klaus Honscheid, Ohio State University (p29)

30 Is there a problem? SLAC Summer Institute Klaus Honscheid, Ohio State University (p30)

31 Waiting for a V ub update Exclusive (B -> ρlν or πlν) V ub = (3.25+/ /-0.55)x [CLEO] Inclusive (b -> X u lν) V ub / V cb = 0.8 +/- 0.2 Rare hadronic decays (e.g. B->ππ) B->D (*) s π +(0) B -> τν [LEP, CLEO] (seen) (not seen) SLAC Summer Institute Klaus Honscheid, Ohio State University (p31)

32 Pure leptonic decays: B -> τν BR( B GF mbml m + l fi l + 2 n) = 1- fb V 2 2 ub 8p mb Ł ł t B b u W l ν Standard Model: B -> τν ~ (0.2-1) x 10-4 Idee: fully reconstruct on B, look for τ + missing energy Using 9.7 x 106 BB events we find BR(B -> τν ) < 8.4 x 10-4 Bonus: BR(B -> Kνν ) < 2.4 x 10-4 SLAC Summer Institute Klaus Honscheid, Ohio State University (p32)

33 Rare B Decay Tree: u Penguin: u s u u u K π 0 s π d u K s d u u u π 0 π Tree decays b u vs. b c suppressed by V ub 2 / V cb 2 ~ 0.01 Additional V us 2 / V ud 2 ~ 0.04 for K Expect tree dominantly b uud. Decays b s,d GIM-suppressed Loop diagram (m t /m W ) 2. V td 2 / V ts 2 ~ 0.01 Expect penguins dominantly b uus. SLAC Summer Institute Klaus Honscheid, Ohio State University (p33)

34 B K + π /π + π Topology B fi Kp e + e -- fi qq P daughter ~ GeV/c (higher than for b c decays) Major background from e + e - qq continuum Continuum events are jetty in topology P B ~ 300 MeV/c BB events spherical Continuum suppression from ML fit to several kinematic and topological variables (more efficient). Continuum suppression factor of ~ 10 6, efficiency for Kπ/ππ of ~ 40% SLAC Summer Institute Klaus Honscheid, Ohio State University (p34)

35 K/π Separation Kπ vs. ππ from de/dx in drift chamber Resol. confirmed with D * D 0 π, D 0 K π + Also separation from kinematics: Pions Kaons E ππ = E π + E π - E beam Kπ ππ CLEO data E resolution studied with D 0 K π + (π 0 ) mass resolutions σ E E (de/dx - Expected)/σ de/dx CLEO II 25 MeV 1.7σ 1.7σ E ππ (GeV) CLEO II.V 20 MeV 2.1σ 2.0σ SLAC Summer Institute Klaus Honscheid, Ohio State University (p35)

36 Fit Results for B Kπ, B ππ Fit Results for B Kπ, B ππ SLAC Summer Institute Klaus Honscheid, Ohio State University (p36)

37 B Kπ, B ππ Summary π + π π + π 0 π 0 π 0 K + π K + π 0 K 0 π + K 0 π 0 K + K K + K 0 Signal (events) # σ ε (%) ± ± ± ± BR ( 10-6 ) < 12.7 < < 1.9 < 5.1 SLAC Summer Institute Klaus Honscheid, Ohio State University (p37)

38 Exclusive b u Transitions Many hadronic b u transitions observed New study includes 14 channels (hep-ex/ ) In general - good agreement with theory Full Dalitz analyses could determine α and γ SLAC Summer Institute Klaus Honscheid, Ohio State University (p38)

39 Likelihood Contours B ρ + π/ρκ and B ρ 0 π/ρκ fitted simulataneously BR(B ρ + π)/br(b ρ 0 π) smaller than expected (>4) SLAC Summer Institute Klaus Honscheid, Ohio State University (p39)

40 Modes with η and η SLAC Summer Institute Klaus Honscheid, Ohio State University (p40)

41 Pure Penguins: B φκ SLAC Summer Institute Klaus Honscheid, Ohio State University (p41)

42 arg(v ub ) (= γ ) from Decay Rates Fleischer-Mannel (Phys. Rev. D57, 2752(1998)) Γ(B 0 K π + ) R sin 2 γ CLEO: R = 1.01 ± 0.26 Γ(B + K 0 π + ) Neubert-Rosner (Phys. Lett. B441, 403 (1998)) R * Γ(B + K 0 π + ) 2Γ(B + K + π 0 ) (1-R * )/ε 3/2 δ EW - cosγ 0.58 ± 0.74 (0.64 ± 0.15) - cosγ Also model-dependent fit to many CLEO branching ratios of ππ, Kπ, ρπ, ωπ (Wuerthwein et al. hepex/ ): 84 < γ < 154 (90% C.L.) SLAC Summer Institute Klaus Honscheid, Ohio State University (p42)

43 CP Asymmetries Measure B and B reactions described by two amplitudes: Γ(B f) = a 1 e i(φ 1+δ1) + a 2 e i(φ 2+δ2) 2 Γ(B f) = a 1 e i( φ 1+δ1) + a 2 e i( φ 2+δ2) 2 CP asymmetry from strong and weak phase differences (Γ Γ) / (Γ + Γ) sin(φ 1 φ 2 )sin(δ 1 δ 2 ) Depends upon comparable magnitudes as well CLEO can measure decays that are sensitive to γ = arg(v ub *) B + K + π 0, B + K 0 π +, B + K + η SLAC Summer Institute Klaus Honscheid, Ohio State University (p43)

44 A cp Expectations Factorization model calculations (no FSI interactions) Ali, Kramer, Liu, hep-ph/ K + π » K + π K 0 π » K + η ωπ Final state interactions may boost A CP ~ 20-40%. He et al, Phys. Rev. Lett. 81, 5738 (1998) Neubert, JHEP 9902, 014 (1999) Deshpande et al., Phys. Rev. Lett. 82, 2240 (1999) New physics could boost A CP ~ 40-60%. He et al., hep-ph/ SLAC Summer Institute Klaus Honscheid, Ohio State University (p44)

45 Experimental Bias(es) B flavor tagged by high momentum track Must demonstrate reconstruction not charge dependent. Charge difference in K - N and K + N cross sections Track reconstruction difference confirmed in Monte Carlo ~ SLAC Summer Institute Klaus Honscheid, Ohio State University (p45)

46 CP Asymmetry Results events events events events events K - p + K + p 0 K 0 p + K + h wp + 90% C.L. A CP SLAC Summer Institute Klaus Honscheid, Ohio State University (p46)

47 CP from New Physics? 126 ± 15 events Penguin amplitude V ts Other amplitudes, CP, small in SM Some Higgs models introduce CP, possibly even if b sγ rate unaffected. Wolfenstein & Wu, Phys. Rev. Lett. 73, 2809 (1998) Asatrian & Ioannissian, Phys. Rev. D54, 5642 Kagan & Neubert, Phys. Rev. D58, B Candidate Mass (GeV/c 2 ) SLAC Summer Institute Klaus Honscheid, Ohio State University (p47)

48 b sγ Results Updated branching ratio results: Monte Carlo BR(B 0 K *0 γ) = (4.5±0.7±0.3) 10-5 BR(B + K *+ γ) = (3.8±0.9±0.3) 10-5 BR(B K 2* (1430)γ) = (1.6±0.55±0.13) 10-5 CP asymmetry from special kinematic region for best K/π identificatio A CP = 0.08 ± 0.13 ± 0.03 Asymmetry for inclusive b sγ (based on 9.7M BB pairs only): A CP = ± ± or < A CP < 0.09 (90% C.L.) Upper limit on b d exclusive penguins: BR(B (ρ,ω )γ) < ~10-5 SLAC Summer Institute Klaus Honscheid, Ohio State University (p48)

49 Search for b dγ Expect that B ργ also described by penguin amplitude dominant top? Γ(B ργ) V td 2 Γ(B K * γ) V ts 2 = ξ ξ Updated branching ratio limits: BR(B 0 ρ 0 γ) < BR(B + ρ + γ) < BR(B 0 ωγ) < BR(B ργ)/br(b K*γ )<0.32 (90%CL) K * g rg V td /V ts < 0.72 (90%CL) SLAC Summer Institute Klaus Honscheid, Ohio State University (p49)

50 Searches for D 0 -D 0 Mixing π - K + x= M/Γ y= Γ/2Γ π +,K + π -,K - SLAC Summer Institute Klaus Honscheid, Ohio State University (p50)

51 Right and Wrong-Signed D 0 Decays Use tagged D 0 s from D *+ decays: p + s D *+ D 0 K - p + Sign of slow π tags initial D 0 flavor Sign of K tags final D 0 flavor, unless DCSD p + s D *+ D 0 p s D *+ _ D 0 D 0 SLAC Summer Institute Klaus Honscheid, Ohio State University (p51) K + p - + K + p -

52 D 0 -> K + π - Final State Definitions: Γ R 0 R = Γ ( 0 + D K π ) ( + D K π ) RM + RD + RD y ( 2 2 x ) R M = y Strong phase, δ, between DCSD and CFD y = y cosδ x sinδ x = x cosδ y sinδ R [ 2 2] 2 t x + y t e SLAC Summer Institute Klaus Honscheid, Ohio State University (p52) D + R D y t + 1 4

53 A Charm Event in CLEO II.V SLAC Summer Institute Klaus Honscheid, Ohio State University (p53)

54 Charm Reconstruction and Lifetime Method CESR beamspot is a ribbon σ x ~ 350 µm σ y ~ 10 µm σ z ~ 2 cm Reconstruct 3D beamspot and decay vertices Use only y flight information to calculate proper time t D 0 =(y vtx y beamspot ) m D 0/cp y SLAC Summer Institute Klaus Honscheid, Ohio State University (p54)

55 Right-signed Decays: D 0 -> K - π + D *+ -> D 0 π +, D 0 -> K - π + σ M = 6.4 MeV/c 2 σ Q ~ 190 KeV σ τ = 0.35 τ D 0 SLAC Summer Institute Klaus Honscheid, Ohio State University (p55)

56 Wrong-signed Decays: D 0 -> K + π - D *+ ->D 0 π + flavor tagging Reject CFD and SCSD candidates with D 0 ->π + K -, π + π -, K + K - mass hypotheses within 4σ of D 0 mass 2D Binned ML Fit in Q vs M Kπ Signal Shapes WS signal shape taken from RS signal Background shapes from MC Phys. Rev. Lett. 84, 22 (2000) SLAC Summer Institute Klaus Honscheid, Ohio State University (p56)

57 D 0 -> K + π - Decay Time Dependence WS signal fit to function t [ ] R D + RD y t + x + y t e 4 combined with resolution function Parameter Best Fit 95% C.L. R D (0.48 +/ /- 0.04)% 0.24% < R D < 0.71% y ( /- 0.3)% -5.8% < y < 1.0% x (0 +/ /- 0.2)% x < 2.9% (1/2)x 2 < 0.041% SLAC Summer Institute Klaus Honscheid, Ohio State University (p57)

58 Results R R δ M D δ RM ( 1 ± AM ) (analogous to ε) RD ( 1 ± AD ) (analogous to ε ) ( 1 ± φ) (analogous to sin 2β) Parameter Best Fit A A M D ± 0.01 ± 0.01 sin φ 0.00 ± 0.60 ± 0.01 Limit -36% < A D < 30% (95% C.L.) SLAC Summer Institute Klaus Honscheid, Ohio State University (p58)

59 First Observation of D 0 ->K + π - π 0 N N WS RS = = (from fit) ± 7 (sys) SLAC Summer Institute Klaus Honscheid, Ohio State University (p59)

60 D Mixing Prospects CP Eigenstates (e.g D 0 -> KK, ππ) lifetime analysis probes y= Γ/2Γ directly. p + p - Expect σ y ~ 1.8% (stat. + sys.) Semileptonic Decays D 0 -> K *+ lν No DCSD, so R D = 0 and R = R M Estimate sensitivity R M < 0.15% SLAC Summer Institute Klaus Honscheid, Ohio State University (p60)

61 Search for CP Violation Using D 0 -> KK, ππ A CP 0 0 N ( D f ) N ( D ( f ) = 0 0 N ( D f ) + N ( D f f ) ) A CP ( KK ) = (0.04 ± 2.18( stat) ± 0.84( sys))% A CP ( ππ ) = (1.94 ± 3.22( stat) ± 0.84( sys))% SLAC Summer Institute Klaus Honscheid, Ohio State University (p61)

62 CLEO III 1999 Solenoid coil Barrel calorimeter RICH Drift chamber Silicon Vertex Endcap calorimeter SC quad pylon SC quads Rare earth quad 2000 Magnet iron SLAC Summer Institute Klaus Honscheid, Ohio State University (p62)

63 Hadronic Event SLAC Summer Institute Klaus Honscheid, Ohio State University (p63)

64 CLEO III Performance Design Value 150um Mean 102um SLAC Summer Institute Klaus Honscheid, Ohio State University (p64)

65 RICH Principle Methane-TEA MWPC LiF radiator K/p g CaF2 windows g N2 expansion gap SLAC Summer Institute Klaus Honscheid, Ohio State University (p65)

66 We are no longer alone... PEP II CESR 15 fb -1 2 fb -1 Int. L 2.3x10 33 cm -2 s x cm -2 s -1 Inst. L (1.7x cm -2 s -1 ) BABAR CLEO III 20 mm? Si res. 125 mm 100 mm aver. DR res. 100 mm 75 mm best DR res. 7.5 % 5.0% de/dx, Bhabha 7.2 MeV 5.4 MeV p 0 res. works works PID 70 Hz 70 Hz Events to tape 1% 1% DAQ deadtime SLAC Summer Institute Klaus Honscheid, Ohio State University (p66)

67 CESR III Superconducting RF More Power 1 A beam current Less Impedance 4 RF cells vs. 20 Reduced Instabilities Higher Gradient Shorter Bunches Superconducting Quads Better focus b* from 18 to 13 mm Spring 2001 SLAC Summer Institute Klaus Honscheid, Ohio State University (p67)

68 Conclusions Hadronic B Decays still interesting Extended Factorization tests New Charmonium decay modes Intriguing interference pattern in charged B decay Large V cb from exclusive decays New results on rare B First observation of B->φπ, many new modes New limit on B->π 0 π 0 Limits on CP asymmetries Limits on D 0 -D 0 mixing and CP violation CLEO III up and running SLAC Summer Institute Klaus Honscheid, Ohio State University (p68)