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Recent Results from BABAR Selected Contributions to LP and EPS

α. V td V tb *. V ud V ub *. β. γ. V cd V cb *. Recent Results from BABAR Selected Contributions to LP and EPS. SLAC Experimental Seminar September 6, 2005 Helmut Marsiske , SLAC. Outline. Apologies: 75 BABAR abstracts@LP05 ~2/3 rd of them not covered here.

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Recent Results from BABAR Selected Contributions to LP and EPS

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  1. α VtdVtb* VudVub* β γ VcdVcb* Recent Results from BABARSelected Contributions to LP and EPS SLAC Experimental Seminar September 6, 2005 Helmut Marsiske, SLAC

  2. Outline Apologies: 75 BABAR abstracts@LP05 ~2/3rd of them not covered here Noticeabsence of Pentaquark bullet • New States • Y(4260), X(3872) • Searches for New Physics (NP) • Radiative penguins • bs/d, bsl+l- • Input for CKM matrix elements • Unitarity Triangle (UT) sides and angles • |Vub|, |Vtd/Vts| • β from trees and penguins • α, γ • Rare B and decays • B and e/μ Helmut Marsiske, SLAC Recent BABAR Results

  3. X(3872)J/+- JPC= 1  y(2S),y(3770), … • Belle: discovery • Unexpected discovery mode for charmonium state above open-charm threshold • BABAR: search for X(3872)J/+- in Initial State Radiation (ISR) Events • ISR  e+e- collisions with a continuum of center-of-mass (CM) energies below the (4S) • Search final state PRL 91, 262001 (2003) Helmut Marsiske, SLAC Recent BABAR Results

  4. No sign of X(3872) in ISR but observation of Y(4260)J/+- (2S) • 123±23 events; >8σ statistical significance • Mass (4258±8)MeV; just above DSDS threshold • Total width (88±23)MeV hep-ex/0506081 232fb-1 Peak cross section ~50pb Helmut Marsiske, SLAC Recent BABAR Results

  5. No evidence for Y(4260) in R-scan Y(4260) R √s (GeV) • Dip in R at √s=4.26GeV R≈3 and σ=(14.2±0.6)nb Y(4260) decay mode  conventional charmonium interpretation does not fit well Factors >10 and >20 larger than J/+- partial width of (2S) and (3770), resp. Helmut Marsiske, SLAC Recent BABAR Results

  6. Indication of Y(4260) J/+-in B decay • Search for • 3.1σ significance, assuming mass and width from ISR analysis; needs confirmation hep-ex/0507090 232M BB Helmut Marsiske, SLAC Recent BABAR Results

  7. (New) Physics in loop diagrams • Radiative penguins • bs/d: flavor-changing neutral current absent at tree-level in Standard Model (SM) • Sensitivity to new particles in the loop, e.g., SUSY Higgs • NP can affect bs/d branching fractions (BFs), direct CP asymmetry, isospin asymmetry, … Helmut Marsiske, SLAC Recent BABAR Results

  8. Solid SM predictions… …for inclusive bs/dquantities in the framework of Operator Product Expansion (OPE) and quark-hadron duality • Inclusive BF (E≥1.6GeV) • B(BXs)TH = (3.57 ± 0.30) x 10-4 (SM NLO, Buras et al.) • B(BXs)TH = (3.79 ) x 10-4 (SM NLO, Hurth et al.) • Direct CP asymmetry • ACP(BXs+d)TH≈ 0 + 0.39  0.53 Helmut Marsiske, SLAC Recent BABAR Results

  9. Backgrounds and model dependence MC • Experimental challenge: eliminate very large continuum and BB backgrounds (BGs) without cutting on  orXs • Any such cuts introduce model dependence Correct for missing part of E or Xs spectrum Helmut Marsiske, SLAC Recent BABAR Results

  10. Fully-inclusive bs/d hep-ex/0507001 • No requirements on Xs/d system • Suppress continuum BG by topology cuts and requiring “lepton tag” from recoiling B • Subtract remaining continuum with off-resonance data • Suppress BB BG by vetoing photons from 0s and s • Subtract remaining BB BG using MC validated with control samples MC after cuts Lepton tag reduces signal by x20 and continuum BG by x1200 Helmut Marsiske, SLAC Recent BABAR Results

  11. Semi-inclusive bs qq ( fixed from MC) Non-peaking BB peaking BB (fixed from MC) hep-ex/0508004 • Reconstruct as many of the Xs final states as possible: Xs  K + n+ m0, K=K±, K0S , n,m4 89M BB 55% of final states reconstructed 45% missing; mostly K0L (assumed  K0S) and K + ≥5(0) Signal Helmut Marsiske, SLAC Recent BABAR Results

  12. Fully-inclusive Measures E in CM frame w/ resolution of ~40MeV Semi-inclusive Measures m(Xs) in B frame w/ resolution of ~5MeV  K* peak visible Photon energy spectrum from 89M BB fits Helmut Marsiske, SLAC Recent BABAR Results

  13. BF and CP asymmetry Note width of SM prediction In good agreement with SM predictions • Total BF from semi-inclusive partial branching fraction by extrapolating to E=1.6GeV • CP asymmetry using fully-inclusive lepton tag Helmut Marsiske, SLAC Recent BABAR Results

  14. bs input for |Vub| B g g Confinement b b 2-body decay s Xs • Moments/shape of E spectrum  determination of OPE parameters mb and µ2 • Same parameters needed to convert PBF for into |Vub| • 1st moment 2nd moment Also from lepton-energy and hadronic-mass moments in BXCl b-quark mass (b-quark kinetic energy)2 Helmut Marsiske, SLAC Recent BABAR Results

  15. bs 1st and 2nd momentsvs minimum photon energy Theory is Bigi, Benson and Uraltsev (BBU) (NP B 710, 371 (2005)) using BABAR measured B->Xcln moments(PRL 93, 011803 (2004)) Good agreement with theory (BBU) and previous measurements Helmut Marsiske, SLAC Recent BABAR Results

  16. Fits to Emoments and Espectrum in “kinetic scheme” by Bigi, Benson, Uraltsev (BBU) and “Shape Function (SF) scheme” by Bosch, Lange, Neubert, Paz (BLNP) OPE parameter fits in different theoretical schemes Fits and plot thanks to O. Buchmueller and H. Flaecher Fits to E spectrum (semi-inclusive only) Extraction of OPE param- eters and application to |Vub| ongoing; more later Fits to E + BXclmoments (fully- and semi-inclusive) Helmut Marsiske, SLAC Recent BABAR Results

  17. Exclusive bs/d • Exclusive decays like BK* , Bexperimentally easier • Theoretical predictions for BFs less firm • Need formfactors for B  K*/ transition • Different approaches: Light Cone Sum Rules (LCSRs), lattice QCD (LQCD), … • Reasonably precise predictions for • Ratios of BFs • CP and isospin asymmetries • Forward-backward (FB) asymmetry in Helmut Marsiske, SLAC Recent BABAR Results

  18. Search for B/ in 211M BB • No significant signals observed; upper limit (UL) • Recent claim by Belle for B0 observation PRL 92, 111801 (2004) BABAR low compared to theory 2.7σ below Belle in B0 Helmut Marsiske, SLAC Recent BABAR Results

  19. bs input for |Vtd/Vts| Ali and Parkhomenko, Eur.Phys.JC 23,89 (2002) Ali et al, PLB 595,323 (2004) difference in dynamics (such as W-annihilation) DR  0.10.1 form factor ratio z2  0.850.1 (largest uncertainty) • SM prediction for ratio of BFs • Use BABAR B0 UL together with earlier measurement • Radiative penguins starting to provide meaningful constraints on one side of the UT; more later… B(B+→K*+) = (39.2  2.0  2.4) x 10-6 B(B0→K*0) = (38.7  2.8  2.6) x 10-6 PRD 70, 112006 (2004) 88M BB Helmut Marsiske, SLAC Recent BABAR Results

  20. Exclusive bs l+l- SM diagrams W+ W– box EW penguin SUSY diagram • Exclusive decays like BK(*)l+l- • SM predictions for BFs, CP asymmetries, forward-backward (FB) asymmetries • NP can affect any of these quantities Helmut Marsiske, SLAC Recent BABAR Results

  21. BK(*)l+l- results from 229M BB Smallest B-meson BFs measured hep-ex/0507005 • BFs • CP asymmetries • FB asymmetries: coming soon Helmut Marsiske, SLAC Recent BABAR Results

  22. (New) Physics around the UT Apex at in (extended) Wolfenstein parameterization α VtdVtb* VudVub* β γ VcdVcb* • UT consistency • “global”: sides vs. angles • “local”: angles from trees vs. penguins • Need good metric to compare to when looking for NP • Two sides (|Vcb|, |Vub|) and one angle (γ) determined from tree-level processes  free of NP • Third side: |Vtd| from mixing box-diagram, i.e., Δmd ; phase β of Vtd from mixing-induced CP- violating asymmetry in B0J/K0 tree decay Helmut Marsiske, SLAC Recent BABAR Results

  23. NP in mixing-related quantities? 2sCL 1s CL http://utfit.roma1.infn.it NP SM=(1,0) • Check for NP in terms of parameters Cd and d No sign of NP in Bd mixing, but limits are still weak Helmut Marsiske, SLAC Recent BABAR Results

  24. Status of UT constraints α VtdVtb* VudVub* γ β VcdVcb* • Constraints from UT sides and sin2β from charmonium tree decays free of NP  excellent yardstick • Good overall agreement • Slightly worse since LP05 due to lower sin2β: • Indirect determination http://ckmfitter.in2p3.fr sin2β not used in fit (HFAG) (CKMfitter) Belle: sin2β=0.728±0.0610.652±0.044 Helmut Marsiske, SLAC Recent BABAR Results

  25. UT sides: |Vub| α VtdVtb* VudVub* γ β VcdVcb* • Crucial to fix UT parameters valid in “any” NP extension of SM • Complementary to sin2β – the side opposite the angle • Best measured in (charmless) semileptonic decays • From inclusive (partial) BFs using OPE • From exclusive (partial) BFs using form factors (FFs) • LCSRs, LQCD, quark models, … Helmut Marsiske, SLAC Recent BABAR Results

  26. |Vub| from inclusive BFs • OPE reliably predicts total decay rate • Experiments measure PBFs in restricted phase space region  severe cuts against overwhelming background • Extrapolate from PBF to total decay rate and |Vub| need OPE parameters describing non-perturbative effects • Measure OPE parameters from moments and spectra of and distributions • Two theoretical approaches • “kinetic scheme” by BBU • “Shape Function (SF) scheme” by BLNP et al. • Three approaches within SF scheme (“DFN”, “BLL”, “BLNP”) Helmut Marsiske, SLAC Recent BABAR Results

  27. Inclusive |Vub| measurements 10% variation in |Vub| for the same PBF due to different theoretical approaches and/or OPE parameter inputs signal region sideband region signal +0.46 –0.38SF |Vub|=(4.65±0.34exp ±0.23theo)´10-3 +0.58 –0.42HQ +0.42 –0.38SF |Vub|=(4.44±0.25exp ±0.22theo)´10-3 |Vub|=(3.95±0.26exp ±0.25theo)´10-3 • Electron endpoint spectrum • Electron and neutrino momentum • Lepton and hadronic system recoiling against fully-reconstructed B mesons 88M BB hep-ex/0408075 89M BB hep-ex/0506036 232M BB hep-ex/0507017 Helmut Marsiske, SLAC Recent BABAR Results

  28. |Vub| from exclusive BFs 1: 2: 1: • Need FFs to describe transition of B meson to light meson • Not all theoretical approaches work for all light mesons or all q2 regions • LCSR:  and  and q2<14GeV2 • LQCD: only  and q2>15GeV2 • FF uncertainties affect measurement twice • FF shape  acceptance • Measure with data to reduce dependence on theoretical predictions • FF normalization  extraction of |Vub| from PBF • 10-13% error for LCSR and LQCD in their respective validity ranges; 15-17% error for full q2 range Helmut Marsiske, SLAC Recent BABAR Results

  29. Exclusive |Vub| measurements: untagged pln rln 7% exp. 4% 6% |Vub| = (3.82 ± 0.14 stat ± 0.22 syst ± 0.11 FF– 0.52 LQCD ) + 0.88 83M BB Bl hep-ex/0507003 • mES distributions • q2 distribution -0.15<ΔE<0.25 GeV LQCD and LCSR agree well with data; ISGW-II marginal LQCD2: FNAL 2004 Fit to Data using Becirevic- Kaidalov (BK) parameterization Helmut Marsiske, SLAC Recent BABAR Results

  30. Exclusive vs. inclusive |Vub| measurements +0.87 –0.51LQCD |Vub|=(3.76±0.16exp )´10-3 Indirect |Vub| determination • Exclusive • Much improved expt. error: 4% • Theory error still dominant: ≥15% • Experimental input, i.e., FF shape, will reduce theory error in the future • Inclusive • Much improved expt. error: 4% • Very much improved theory error ( OPE parameters): 6% (HFAG) |Vub|=(4.38±0.19exp±0.27mb,theory)´10-3 (HFAG) Helmut Marsiske, SLAC Recent BABAR Results

  31. UT sides: |Vtd/Vts| α VtdVtb* VudVub* γ β VcdVcb* 2sCL 1sCL • Constraint used to come entirely from • Ratio better than Δmd alone since smaller theoretical uncertainty on • Now radiative penguins sufficiently precise to start providing meaningful UT constraints • Low B/ BF favors small |Vtd| Helmut Marsiske, SLAC Recent BABAR Results

  32. UT angles: β • Mixing-induced CP violation (CPV): Interference of decay amplitudes w/o and w/ mixing • Time-dependent (TD) B0-B0 CP asymmetry Mixing: t: time difference between B0 and B0 decays For charmonium tree decays Helmut Marsiske, SLAC Recent BABAR Results

  33. sin2β: bc trees vs. bs penguins SM tree and SM t-penguin: /K0 NP in penguin: K0/η’ • SM tree decay: SM penguin decay: bccs bsss/sdd • Penguin sensitive to new particles in the loop SM caveat: t/u-penguin ≠ Helmut Marsiske, SLAC Recent BABAR Results

  34. NP in sin2β ???bc trees vs. bs penguins bc WA: S=0.687±0.032 • All but one measurement below bccs average • Naïve bs average 2.7σ below bc average • SM caveat: buus ampli-tude, color-suppressed tree, w/ phase γ can affect sin2β extraction in all channels w/ neutral, non-strange mesons • Pure bsss channels unaffected by CS tree -η S naïve bs average: S=0.440.09 No evidence of direct CPV Helmut Marsiske, SLAC Recent BABAR Results

  35. Estimates of deviationsin2β(bs) - sin2β(bc) QCD factorization • Expected deviation in QCDF • Always positive – opposite to experiment • Generally small – in some cases extremely small • Consistent w/ estimates from SU(3)-flavor – those are unsigned and assume worst case for the strong phase • Need better experimental precision, in particular in clean bs modes [Beneke, hep-ph/0505075] [Cheng,Chua,Soni, hep-ph/0506268] sin2β(bs) - sin2β(bc) Helmut Marsiske, SLAC Recent BABAR Results

  36. η’K0 channel h’KL h’KS • Combined h’KS+ h’KL BABARh’K0 QCDF SU(3) bound h’KL sample after L(Sg)/[L(Sg)+L(Bg)] cut hep-ex/0507087 • η’K0S channel smallest error on sin2β based on 804±40 events • Add 50% more events in η’K0L channel 232M BB Helmut Marsiske, SLAC Recent BABAR Results

  37. CPV in bs penguins 2.7s? This could be one of the greatest discoveries of the century, depending, of course, on how far down it goes… • Intriguing difference from bc remains Helmut Marsiske, SLAC Recent BABAR Results

  38. UT angles: α Vtd Vtd * Vub 0 0 d d α=180°-β-γ • Interference between mixing amplitude (Vtd) and bu decay amplitude (Vub), e.g., • TD CP asymmetry • Single decay diagram Additional decay diagram i.e., single weak phase with different weak phase   Use isospin-SU(2) symmetry to estimate deviation α-αeff Helmut Marsiske, SLAC Recent BABAR Results

  39. Measuring  in B decays α = 100º  13º 79º< α <123º @ 90% C.L • BFsix times larger than B • Small penguin contribution: |-eff |<11o @ 68% CL • ’s nearly fully longitudinally polarized  almost pure CP-even state •  TD CP asymmetry yields strongest single constraint on  • Note mirror solution around 170o hep-ex/0503049 232M BB Helmut Marsiske, SLAC Recent BABAR Results

  40.  from B// decays http://ckmfitter.in2p3.fr • All three modes give con-sistent and complemen-tary measurements of  •  is not a CP eigen-state, but allows TD analysis of 3 Dalitz plot • Weak constraint at 90% CL, but disfavors  mirror solution near 170o •  constraint very weak at 90% CL due to large penguin contamination Helmut Marsiske, SLAC Recent BABAR Results

  41. UT angles: γ • From direct CPV in the decay of charged B mesons • Interfering tree amplitudes w/ CP-violating relative weak phase γ and CP-conserving relative strong phase δ • Interference if D0/D0 decay into identical final state • CP-eigenstate decay: Gronau-London-Wyler (GLW) • Doubly-Cabibbo-suppressed (DCS) decay: Atwood-Dunietz-Soni (ADS) • Dalitz plot analysis of 3-body decay, e.g., : Giri-Grossman-Soffer-Zupan (GGSZ) bucs bcus Helmut Marsiske, SLAC Recent BABAR Results

  42. bu/bc amplitude ratio rB • Sizable interference only if large enough amplitude ratio • CKM factors x color suppression (CS)  rB≈0.1-0.2 • BABAR has found rB to be around 0.1 • Error on γ strong function of rB • rB≈0.12  30o error on γ w/ current BABAR data  need to add more channels/data Helmut Marsiske, SLAC Recent BABAR Results

  43. New GLW and ADS signalsin Right Sign Wrong Sign 232×106BB ~90 events ~4 events D0 →flavour non-CP B+ D0 CP+→K+K-, p+p- B- WSB+ WSB- B+ B- D0 CP-→K0Sp0, K0Sw, K0Sf NCP+=37.6±7.4 andNCP-=14.8±5.9 mES (GeV/c²) hep-ex/0507002 hep-ex/0508001 CP-eigenstate decay DCS decay 232×106BB Helmut Marsiske, SLAC Recent BABAR Results

  44. GGSZ Dalitz plot (DP) analysis of D0 m2- m2+ D0 +rBei(-g+dB) A(B-) = |A(D0K-)| × m2- m²+ • Sketch of interfering bc and bu amplitudes • CP-conjugate B- and B+ decay amplitudes Assumes CP-conser- vation in D decay Helmut Marsiske, SLAC Recent BABAR Results

  45. DP analysis of D0/D0 decays • Extract D0/D0decay amplitudes from DP analysis of independent cc sample with flavor-tagged decays from • New K-matrix model: 9 BW resonances + K-matrix formalism for  s-wave • Deals with broad, overlapping, multi-channel scalar resonances • Fit fraction 116% 228fb-1 250k D0s hep-ex/0507101 Helmut Marsiske, SLAC Recent BABAR Results

  46. GGSZ Dalitz plot (DP) analysis of • Analyze B-decay DPs using D-decay amplitudes • Fit at each point in B-decay DP • Extract angle γ, amplitude ratios r(*)B and strong phases δ(*)B • Different modes  same γbut different r()B and δ()B γ from bu/bc Interference term Helmut Marsiske, SLAC Recent BABAR Results

  47. Signals in all modes 227×106 BB ~ ~ ~ ~ ~ Mode Signal events D0K- D*0[D00]K- D*0[D0]K- ~ B-D0K− 282 ± 20 ~ ~ B-D*0[D00]K− 90 ± 11 ~ ~ B-D*0[D0]K− 44 ± 8 ~ B-D0K*−[K0Sp-] 42±8 ~ B-D0K*−[K0Sp-] NEW (mES>5.27 GeV/c²) hep-ex/0507039 hep-ex/0507101 Helmut Marsiske, SLAC Recent BABAR Results

  48. GGSZ DP analysis results: γ vs. r(*)B ~ ~ ~ D0K- D*0K- D0K*- 2sCL g(deg) 1s CL (stat.+syst. uncertainties) 2 fold (±p) ambiguities for bothganddB rB k.rsB (<0.75 @ 2s CL) r*B hep-ex/0507101 all D()K() modes combined: γ=(67±28(stat)±13(syst)±11(DP))o Will be 3o with K-matrix model Helmut Marsiske, SLAC Recent BABAR Results

  49. γ from BD()K()with GLW, ADS, and GGSZ methods + GLW/ADS (WA) • Three theoretically clean methods in place to measure γ • Small r()B values very hard meas-urement, but no longer “mission impossible” • To improve precision, need (much) more data/ channels Helmut Marsiske, SLAC Recent BABAR Results

  50. Rare decays: B hep-ex/0507069 • W-annihilation in SM • CKM and helicity suppressed • Measurement of fB with |Vub| from semileptonic decays • Test of LQCD fB calculations • Test of NP • e.g., charged Higgs can significantly enhance BF Helmut Marsiske, SLAC Recent BABAR Results

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