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Hadronic B and D decays studies at B A B AR

Hadronic B and D decays studies at B A B AR. F. Couderc (LAPP, Annecy) @ Moriond QCD05 On behalf of the B A B AR collaboration. Introduction CP related analysis B +  ( +  -  0 ) D K + decay and asymmetry B  D s + X - light analysis B +  D s +  -

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Hadronic B and D decays studies at B A B AR

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  1. Hadronic B and D decays studies at BABAR F. Couderc (LAPP, Annecy) @ Moriond QCD05 On behalf of the BABAR collaboration • Introduction • CP related analysis • B+ (+-0)D K+decay and asymmetry • B  Ds+ X-light analysis • B+ Ds+ - • B0 Ds+ a0(2)- • B+ K*+0 (K+ 0)0 decay • B+  + & ’+ and others… • Conclusion • Non CP related analysis • B0 Ds*+ D*-decays and Ds BR • Search for B+ D(*)+Ks0decay • B  J/ D decay • c0 production New result Updated result

  2. Introduction (1) Run 1-4 : 244 fb-1 on peak data Run 5 : COMING SOON All results shown here are preliminary

  3. Key variables – Introduction (2) (4S) e-(9 GeV) e+(3.1 GeV) Sig Box (mES)  3 MeV • B energy in the (4S) frame: • Reco’d Energy : EB* = E*Breco • Beam energy : EB* = E*beam  = (10-30) MeV mES :B mass using beam energy E : difference between beam and reco’d energy reco

  4. CP related analysis

  5. B+(+-0)D K+ decay and asymmetry L = 229  106 BB pairs = 0.020.160.03 Two diagrams to reach the same final state  CP Advantage : A(D03)  A(D03) B- B-  3D (E, 2 NN to discriminate background) MLL fit : Nsig = 133  23 events continuum bkg continuum+bb bkg all Signal enriched B = (5.51.00.7)10-6 Possible gmeasurement with a Dalitz analysis technique Fit projection on

  6. sin(2) fromCP violation in : B 0 D+ X-lightdecays with X-light  - , a0- , a2-but this needsr B  Ds+ Xlight– Motivations A(B0 D+ X-light) B 0 B0 2 r= A(B0 D+X-light)  CKM allowed CKM suppressed B0 ( ) A(B0D+X-) B0 Acp~ rsin(2b+g)sin(DmDt) B 0 D+X- A(B0D+X-)

  7. sin(2) fromCP violation in : B 0 D+ X-lightdecays with X-light  - , a0- , a2-but this needsr B  Ds+ Xlight– Motivations A(B Ds+ Xlight) r A(B0 D+X-light) ( ) Trick: Use SU(3) flavor symmetry B 0 B0 CKM allowed less suppressed no CKM allowed background B0 s s s

  8. Xlight  0: B+ Ds+0 decay L = 124  106 BB pairs r= 0.02 r Prediction: B(B0 Ds+ -)=(1.60.3 0.2)10-5 B(B+ Ds+ 0)  0.9 10-5 B(B+ Ds+ 0) < 2 10-4 @ 90% CL (CLEO) Nsig = 12.8 Npeak = 5.4 ± 2.6 Hint of signal but not significant Upper Limit @ 90% CL: B(B+ Ds+ 0) < 2.8 10-5

  9. Xlight  a-0(2) : B0Ds+a-0(2)decay L = 230  106 BB pairs a0(2)- r 1 Due to fa0(2) CKM allowed and CKM suppressedmediated process have same order of magnitude assuming factorization CKM suppressed × fa0(2) a0(2)-  CKM allowed But D+[heavy meson] emitted by the W*. Does factorization still hold ? Test CKM suppressedpredictionsB0 Ds+ a0(2)- fa0 , fa2 small Btheo(B0 Ds+ a0(2)-) 7.3 (1.5)  10-5 B(a-0(2)  -)  100 (15) % Data inconsistent with factorization prediction B(B0 Ds+ a0-) < 4.0 10-5 PRELIMINARY B(B0 Ds+ a2-) < 25 10-5

  10. B+ K*+0 (K+ 0)0 decay L = 232  106 BB pairs State of the art: (10-6) Motivations: • CLEO : B < 31 • factorization: B = 3.3 • SU(3): B = (15-22) • Charming penguins : B = 8.4 • not yet observed • possible large CP asym. • compare with B0 K+-B+K+0 Signal enriched Direct CP violation Unbinned maximum likelihood fit including mES, E, mK* and a Neural Network (for bkg discrimination) : Nsig = 88.5  25.7 PRELIMINARY fit projection on continuum + BB background B= (6.92.01.3)10-6 continuum S= 4.1 Signal enriched = 0.040.290.05 fit projection on

  11. B+  + & ’+ and others… L = 232  106 BB pairs Signal enriched Fit projection onmES Branching ratios in good agreement with theory (Nucl.Phys. B675, 333; Nucl.Phys. B609, 469; PRD69, 074002; PRD68 074012; PRD69, 034001; PRD70, 034020) No CP asymmetry observed • process via bu tree (CKM-suppressed) and bs penguins • B0K0; B0; B++ and B+’+previously unobserved • some of them could have large CP asymmetry (measure of ) • test of QCD factorization or SU(3) flavor symmetry PRELIMINARY

  12. non CP related analysis

  13. B0 Ds*+ D*-decays and B (Ds) L = 123  106 BB pairs Ds reconstructed in - B(B0 Ds*+ D*-)  B(Ds- -) = (8.81  0.86stat)  10-4 % Nsig = 212  19 Npeak = 35  6 Mmiss    hep-ex/0502041 Missing mass for Ds NDs= 7488  342 B(B0 Ds*+ D*-) = (1.880.090.17) % B(Ds- -) = (4.81  0.52  0.38) % PRELIMINARY PDG04 : 3.6  0.9 %

  14. Search for B+ D(*)+K0decay (1) • Motivations: pure annihilation diagram never measured in B+ decays. • Bsuppressed by (fB/mB)2 0.002 compared to tree spectator diagram : in this case BtheoO(10-8) • could be enhanced by rescattering Btheo  O(10-5) • experimental limit: B(B+ D*+ K0) < 9.5 10-5 (CLEO)

  15. Search for B+ D(*)+K0decay (2) L = 226  106 BB pairs Evaluated with MC From a fit to data Results consistent with background fluctuation Upper Limit @ 90% CL: PRELIMINARY B(B+ D+ K0) < 0.5 10-5 B(B+ D*+ K0) < 0.9 10-5

  16. B J/ D decay – intrinsic charm (1) J/D(*) ? J/K(*) (BABAR PRD67, 032002) points : data histogram : prediction from simulation (dotted line) and NRQCD (dashed line) J/ Effect also reported by CLEO Hypothesis : intrinsic charm in B mesons,excess BJ/ D()? Btheo 10-4against 10-8 – 10-7 in perturbative QCDforJ/ D B  J/ D  < 5.2 10-5 @ 90 % CL(BABARhep-ex/0406022)

  17. B J/ D decay – intrinsic charm (2) L = 124  106 BB pairs hep-ex/0503021 By product of J/ K* (K) analysis : D reconstructed in K J/ K With cut on the K mass PRELIMINARY No significant signal coming from resonant K Upper Limit @ 90% CL: B+ B0 K mass B(B0J/ D 0)< 0.64 10-5 B(B+J/ D+)< 6.2 10-5

  18. c0production p*(c0) < 1.2 GeVimplies production with a high mass particle (mass > 2.0 GeV/c2) which could be in part due to b  ccsdecays. (see also BABARPRD70, 091106(RC), indirect observation) c0 produced in both e+e- bb(B mesons) and e+e- cc Study of efficiency-correctedp*(c0) in the e+e- c.m. frame L = 116 fb-1 B(B  c0X)  B(c0  -+) =(2.110.190.25)10-4 BB cc PRELIMINARY (e+e-  cc  c0X) B(c0  -+) = 388  39  41 fb

  19. Lot of new or updated results from BABAR: prepare the future ofCP violation analysis by measuring branching ratios (B+(+-0)DK+, B+K*+0, B0Ds+a-0(2), BX) and/or requested quantities (robtained with B  Ds+ Xlightdecays). Factorization: OK in B   X decays (+SU(3) flavor symmetry) OK in B0 Ds+ a-0 where a heavy particle (Ds) is emitted. New measurement of the Ds branching ratio, improve the relative error by a factor of 2 compared to the present value. Rules out the hypothesis of intrinsic charm in B mesons with upper limits on B  J/ D and B  J/ D. Study of the c0production in B decay : could be due to b ccs transition. Conclusion

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