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B decays to open charm and charmonium from BaBar

B decays to open charm and charmonium from BaBar. Stefania Ricciardi Royal Holloway, University of London On behalf of the BaBar Collaboration 32 nd International Conference on High Energy Physics Beijing, August 16-22 nd ,2004. Outline. Testing models of hadronic B decays

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B decays to open charm and charmonium from BaBar

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  1. B decays to open charm and charmonium from BaBar Stefania Ricciardi Royal Holloway, University of London On behalf of the BaBar Collaboration 32nd International Conference on High Energy Physics Beijing, August 16-22nd,2004

  2. Outline • Testing models of hadronic B decays • Inclusive charm production in B decays • B0 Ds*+ D*- [and Ds  f p+] • B0  D(*)-pp+, B0  D(*)0pp • Exclusive B (cc) K(*), where cc = J/y,y(2S),cc • Charm and Charmonium Spectroscopy: • B decays to DsJ (2317) andDsJ (2460) • X(3872) For new results on B D(*)K(*) and B Ds+r - see L.Cavoto’s talk in the CP violation session All results are PRELIMINARY Stefania Ricciardi, BaBar

  3. s’ c W - c b B- u u Inclusive charm Hadronization models (Heavy Quark Expansion) predict average charm multiplicity in B decays, nc  1.2-1.3 [Bagan et al. PLB351(1995) Buchalla and Dunietz, PLB364(1995) Neubert and Sachrajda, Nucl.Phys.B483(1997)] • We define: • Flavor correlated charm • production from dominant • bc transition • Flavoranti-correlated charm • production from W- cs’ decay [charge-conjugation implied everywhere] Stefania Ricciardi, BaBar

  4. Inclusive charm: a new experimental method • Full reconstruction of one B = Breco • Charm hadron searched for in rest of event, fully reconstructed and correlated with charge of parent B = Brecoil • We correct for: mixing in the B0 sample and background from B0 (B+) in the B+ (B0) sample Breco D0 K Y(4S) B B : p B+ (#) p, r,a1 Y(4S) e- e+ D+, D0, Ds,Lc B-   X Brecoil (# at the time of Breco decay only, for neutral B) Stefania Ricciardi, BaBar

  5. BaBar Preliminary D0 D0 Inclusive charm Signal 127342 Signal 16016 Data sample: 89 million B pairs D+ Blue-shaded areas: true charm particles from background of misreconstructed B Signal 9820 Signal 26229 D- B-anti-correlated D-S D+S Signal 8211 Signal 115 B-correlated • Significant production of • correlated D0 and D+ • Ds correlated • production small. • Anti-correlated dominant. L-c L+c Signal 339 Signal 419 Stefania Ricciardi, BaBar

  6. Inclusive charm: branching fraction B- recoil N(B+RECO) = 85840 ± 1910 B0 recoil N(B0RECO) = 48322 ± 590 • First measurement of • D+s correlated • Sizeable Lc • production Stefania Ricciardi, BaBar

  7. Inclusive charm: nc0, nc- • We findno evidence of • B-Lc+Lc-K looking at the missing mass distribution (obtained from the B 4-momentum, a K and a reconstructed Lc or Lc) • We estimate • B(B-c X) = B(B-Lc- X) - B(B-Lc+ Lc-K)  B(B-Lc- X) • B(B-c X) neglected • Using B(B-(cc) X) = (2.3 ± 0.3) %, we determine separately for the first time: B0 B- Previous results (hep-ex/0112028) 1.175 ± 0.042 (CLEO) 1.230 ± 0.042 (LEP+SLD) 1.206 ± 0.033 (Average) Stefania Ricciardi, BaBar

  8. B0 Ds*+ D*- • New measurement of B(B0 Ds*+ D*-) • Experimental test of factorization at high q2 values:q2~m2(Ds*+) • New measurement of B(Ds+ f p+) used to normalize other Ds+ branching fractions • The present ~25% uncertainty B(Ds+f p+ )= (3.6 ± 0.9)%(CLEO) propagates to all analyses where a Ds(*) is reconstructed Stefania Ricciardi, BaBar

  9. B0 Ds*+ D*-: method • With a partial reconstruction technique, determine B1 = B(B0 Ds*+ D*-) • Fully reconstruct final state with Ds+f p+ and measure B2 = B (B0 Ds*+ D*-) x B (Ds+ f p+) • B (Ds+ f p+)= B2/B1. Many systematics cancel in the ratio. Stefania Ricciardi, BaBar

  10. B0 Ds*+ D*- : partial reconstruction hep-ex/0408040 124 million B pairs • Ds+fromDs*+  Ds+is not reconstructed • Pair D*- ( D0p-) and  , assuming they come from B0 Ds*+D*- • This BaBar Result independent ofB(Ds+ fp+) : Signal: 7414 ± 345 B(B0 Ds*+D*-)=(1.85± 0.09(stat) ± 0.16(syst) )% • in agreement with previous: • and theory (Luo and Rosner,2001):    B(B0 Ds*+D*-)=(1.9± 0.5)% (PDG2004) B(B0 Ds*+D*-)theor=(2.4± 0.7)% Stefania Ricciardi, BaBar

  11. Ds+ f p+:Results • D*andgselectionanalogous to inclusive analysis • Ds+ f(K+K-)p+fully reconstructed • measure branching fraction product: B(B0 Ds*+ D*-) x B (Ds+ f p+) = (8.71  0.78(stat)) x10-4 Dividing by our measurement of B(B0 Ds*+D*-), we obtain B(Ds+ f p+) = (4.71 ± 0.47(stat) ±0.35(syst))% to be compared with Signal 212 ±19 B(Ds+ f p+)= (3.6 ± 0.9)% (CLEO) Readjustment of many results needed! Not used yet for other results in this talk Stefania Ricciardi, BaBar

  12. hep-ex/0408035 124 millions B pairs B0D(*)-pp+ and B0 D(*)0pp • Full reconstruction • Explore dynamics of decays • involving baryons • Multi-body decays to baryons • sizeable, as found by CLEO • & predicted B0D*-pp+ 130 ± 14 B0D-pp+ 238 ± 22 I.Dunitez, PRD (1998) Hou and Soni, PRL (2001) Chua, Hou and Tsai, PRD (2002) B0D*0pp 13 ± 4 B0D0pp 96 ± 11 No evidence of q0c+ @ 3.1 GeV B0D*-pp+ Stefania Ricciardi, BaBar

  13. B (cc) K(*) • Exploring heavy quark dynamics by measurements of exclusive B decay rates to modes allowed in the factorization scheme (charmoniumJPC=1-- or 1++) [12 decay modes]: • B  J/y K(*) • B  y(2S) K(*) • B  cc1 K(*) and suppressed ( measure size of non-factorizable contributions) (JPC=0++ or 2++) [8 decay modes]: • B  cc0 K(*) • B  cc2 K(*) • Measurement of CP asymmetries in the charged modes to search for effects due to “New Physics” [Diehl and Hiller, JHEP 0106 (2001)] • Charmonium reconstructed in • J/y(y(2S))  l+l- • cc J/y Stefania Ricciardi, BaBar

  14. B (B (cc) K(*)) Results hep-ex/0408036 124 million B pairs Channel BR (10-4) PDG2004 B+ J/y K+ 10.55  0.15  0.48 10.0  0.4 B+ cc1 K*+ B0 J/y K0 8.73  0.23  0.30 8.5  0.5 B+ J/y K*+ 14.34  0.36  0.94 13.5  1.0 B0 J/ y K*0 12.92  0.25  0.75 13.1  0.7 B+ y (2S) K+ 6.31  0.33  0.44 6.8  0.4 B0 y(2S) K0 6.60  0.60  0.46 6.2  0.7 B0 cc1 K*0 B+ y (2S) K*+ 6.03  0.85  0.91 9.2  2.2 B0 y (2S) K*0 6.65  0.57  1.00 8.0  1.3 B+ cc1 K+ 5.72  0.24  0.64 6.8  1.2 B0 cc1 K0 4.56  0.39  0.51 4.0 +1.2-1.0 B+ cc1 K*+ 2.89  0.69  0.93 new B0 cc1 K*0 3.19  0.37  0.64 4.1  1.5 Stefania Ricciardi, BaBar

  15. B (cc) K(*):Other Results • Charged/Neutral Ratio assuming equal production of charged and neutral at Y(4S) (i.e., R+/0 =1) • Charge CP Asymmetries • R+/0 (assuming isospin invariance and tB+/ tB0=1.086 ± 0.017 from PDG2004) All measurements compatible with no direct CP asymmetry. Stefania Ricciardi, BaBar

  16. Factorization suppressed decays hep-ex/0408033 124 million B pairs • B+cc0 ( pp,KK) K+observed by Belle and BaBar with B.F. >10-4, i.e., comparable to factorization allowed decays • Radiative BF relatively large for cc2: • B (cc0 J/y g) = (1.18 ± 0.14)% • B (cc1 J/y g) = (31.6 ± 3.3)% • B (cc2 J/y g) =(20.2 ± 1.7)% m(llg) – m(ll) cc1 cc1 cc2 cc2 Upper limits for B cc2K(*) an order of magnitude smaller than B.F. for factorization allowed modesand B cc0K(*) cc0 cc0 No statistical significant signal Stefania Ricciardi, BaBar

  17. Spectroscopy B Mesons Heavenly Gateways to Forbidden States…

  18. Study of B  DsJ(*)+D(*) DsJ*(2317)+, DsJ (2460)+ • Observed by BaBar, Belle and CLEO • Unexpectedly below threshold for DK and D*K, respectively • Consistent with P-wave cs states but other interpretations not ruled out • If cs, observed decays • DsJ*(2317)+ Ds+p0 • DsJ (2460)+ Ds*+p0 are isospin violating  narrow • DsJ (2460)+ Ds+g also observed (and used here to determine J) DsJ(2573)+ Ds1(2536)+ Ds1(2460) Ds0(2317) Ds*+ Ds+ Godfrey-Isgur model S-wave P-wave Stefania Ricciardi, BaBar

  19. B  DsJ (*)+D(*) hep-ex/0408041 Data sample: 122 million B pairs m(DsJ) mES Signal: 88 ± 17 events DsJ*(2317)+  Dsp0 Full reconstruction of the exclusive B decay DsJ(2460)+  Ds*p0 Sum over all D(*)(0) modes 112 ± 14 events We measure: DsJ(2460)+ Dsg 139 ± 17events Stefania Ricciardi, BaBar

  20. B  DsJ (*)+D* Results First measurement of all these modes m(Ds*+p0) m(Dsg ) m(Ds+p0) B.F. Products for BDsJ(*)+D* Stefania Ricciardi, BaBar

  21. B  DsJ (*)+D Results m(Ds*+p0) m(Dsg ) m(Ds+p0) B.F. Products for BDsJ(*)+D in good agreement with Belle results Stefania Ricciardi, BaBar

  22. Ds qh DsJ+(2460) g BDsJ(2460)+D: Helicity J=2 J=1 Data points from m(Dsg) fits corrected for detector acceptance and efficiency J=1 (c2=4.0/4) preferred to J=2 (c2=36.4/4) confirms Belle measurement Stefania Ricciardi, BaBar

  23. X(3872)from B-J/y K-p+p- hep-ex/0406022 117 million B pairs • Discovered by Belle(2003) in B decays • Confirmed by CDF,D0 and BaBar • as narrow state decaying to J/yp+ p- • Nature unknown (Charmonium, • DD* molecule, ccg hybrid?) • Most puzzling: mass @ D0D*0 threshold m(J/yp+p-) y(2S) 30.5 ± 5.8 signal events , after bkg (combinatorial and peaking) subtraction, in 20 MeV: 3.862 < mX <3.882 GeV X(3872) X(3872) y(2S) mX(3782)= 3873.4 ±1.4 MeV/c2 B(B-X(3872)K-)xB(X(3872)J/yp+p-) = (1.28 ± 0.41) x10-5 m(p+p-) Accumulation near kinematic limit in m(p+p-) which is ~m(r0) for X(3872). Isospin-breaking ? More data needed! Stefania Ricciardi, BaBar

  24. Search for BX -(3872)K Data sample: 213 million B pairs m(J/yp-p0) • If observed decay is X(3872)J/yr0 •  charged partner may exist X(3872)-J/yr- • Search for B0X-K+, B-X-K0s • (and charged conjugates)withX-J/y p-p0 • If X isovector,decay rate to X should be twice • that observed for neutral X[BaBar:(1.28 ± 0.41) x10-5] B0 X-? Consistent with peaking background (estimated from mX sidebands) B0 A likelihood ratio test excludes isovector hypothesis (Probability <1/600) mES for |m(X)-3872| < 12MeV Stefania Ricciardi, BaBar

  25. Summary New results on B decays to open and hidden charm from BaBar: • Powerful application of recoil method for first separate determination of nc-and nc0 • Most precise measurement of B0 Ds*+ D*- and Ds branching fractions • Improved measurements of B0  D(*)-pp+, B0  D(*)0pp • Improved results of many exclusive B decays to charmonium, including: • measurement of B+ cc1 K*+ • stringent upper limits on B cc2K(*) • First observation of BDsJ(*)+D* • New insights on X(3872): isovector hypothesis excluded B(Ds+ f p+) = (4.71 ± 0.47(stat) ± 0.35(syst))% Stefania Ricciardi, BaBar

  26. Additional Slides

  27. Ds+ f p+ Data sample 124 million B pairs 1 - Partial reconstruction: Signal 7414 ± 345 Partial reconstruction result independent ofB(Ds+ fp+):    B(B0 Ds*+D*-)=(1.85± 0.09(stat) ± 0.16(syst) )% 2 - Full reconstruction: B(B0 Ds* D*-, Ds f p+) = (8.71  0.78(stat)) x10-4 From the ratio BaBar obtains: Signal 212 ±19 B(Ds+ f p+) = (4.71 ± 0.47(stat) ±0.35(syst))% B(Ds+ f p+)= (3.6 ± 0.9)% PDG2004(CLEO) Stefania Ricciardi, BaBar

  28. c Production B(B-c X) = B(B-Lc- X) - B(B-Lc+ Lc-K) CKM allowed processes 1 Anticorrelated Lc production not many different ways 3 2 Stefania Ricciardi, BaBar

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