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Branching Fraction and Properties of B meson Decays to Charmonium

Branching Fraction and Properties of B meson Decays to Charmonium. Y. Watanabe Tokyo Institute of Technology For the Belle Collaboration. Contents. 1. Introduction KEKB and Belle Interest in 2. Search for Missing Charmonium states 3. Search for factorization-forbidden decays

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Branching Fraction and Properties of B meson Decays to Charmonium

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  1. Branching Fraction and Properties of B meson Decays to Charmonium Y.Watanabe Tokyo Institute of Technology For the Belle Collaboration

  2. Contents • 1. Introduction KEKB and Belle Interest in • 2. Search for Missing Charmonium states • 3. Search for factorization-forbidden decays • 4. Additional CP eigenstates (Cabibbo favored):

  3. Contents (2) • 5. Additional CP eigenstates(Cabibbo suppressed): • 6. Branching Fractions of Exclusive Decays • 7. Summary

  4. 1034 1032 Luminosity (cm-2 s-1) 1030 100 1 10 Center of mass energy (GeV) 1 Introduction • Luminosity vs. Energy of e+e- colliders KEKB

  5. 1 Introduction (2) • Accelerator-Detectors at Luminosity Frontier as of summer 2002 Peak lum. Integrated Lum.Start of (1033cm-2s-1) (fb-1d-1) (fb-1) operation KEKB - Belle 7.35 0.41 89.6 1999 May PEP-II - BaBar 4.6 0.31 93.8 1998 Oct. CESR - CLEO 1.25 0.1 ～ 25 1979

  6. 1 Introduction (3) • KEKB Asymmetric Energy e+e-collider (crucial for CP measurement) at Υ(4S) region (10.58GeV) e- : 8.0 GeV, 1.1A e+: 3.5 GeV, 2.6A finite angle crossing ±11mr World Highest Luminosity Design = 1034 cm-2s-1 Belle

  7. 1 Introduction (4) • Luminosity at KEKB-Belle 0.4 Luminosity/day (fb-1/day) Improved drastically 0.2 89.6 fb-1 90 Integrated Luminosity (fb-1) 45 2001.1 2002.7 1999.5

  8. 1 Introduction (5) • Belle detector Good Vertex Detection Good Particle ID • Belle collaboration ～300 researchers (55 Institutes) from Australia, Austria, China, Germany, India, Japan, Korea, Philippines, Poland, Russia, Slovenia, Switzerland, Taiwan and USA

  9. 1 Introduction • Belle and Logo Asymmetric e+e- collider producing B

  10. 1 Introduction (6) • Interest in B decays to charmonium 1) Golden channels for CP Measurements: 2) Best place to look for missing charmonium states such as ηC(2S) 3) Clean testing ground of Theoretical Ideas (QCD, NRQCD, HQET) charmonium states = singlet in color, isospin and SU(3) quantities 4) Fundamental Quantities Branching fractions, etc.

  11. 1 Introduction (7) • Fundamentals of Analyses 1) Most of analyses are based on data of(1/3 of data taken) 2) Number of events Reconstructable Final state 3) Signals: look for peaks in:

  12. By Crystal Ball collab.(PRL48, 70, 1982)unconfirmed 2 Search for missing States • Charmonium Levels Missing so far

  13. Found this time hadrons hadrons hadrons hadrons hadrons hadrons hadrons 2 Search for missing States (2) • Transitions among Charmonium Levels

  14. 2 Search for missing States (3) • First Observation of ηC(2S)(PRL to be published) B signals found in

  15. ηC(2S) 2 Search for missing States (4) • ηC(2S) (cont’d) Mass (MeV/c2) (MeV) Belle 3654±6 ± 8 <55 Crystal Ball 3594 ±5 <8 Theory 3635 ±10 8.3±1.3 ( PRD24,132(81), Fermilab-Pub02/104-T) #total=64 #Bgd =21±2 (substantial !)

  16. 3 Factorization-Forbidden Decays Factorization

  17. charmonium ・・・ 3Factorization-Forbidden Decays • QCD expectation Naïve Factorization Hypothesis:

  18. 3 Factorization-Forbidden Decays (2) • Decay B→χC2(3556) X found. (PRL to be published) enhance Events look for

  19. 3 Factorization-Forbidden Decays (3) • B→χC2(3556) X cont’d Momentum spectra: little events at end point for compared to essentially no (in contrast to ) 0 0.6 1.2

  20. 3 Factorization-Forbidden Decays (4) PRL88:031802(2002) • found A shift of the peak → interference?

  21. 4 Additional CP eigenstates • Decay modes so far used for CP fitting

  22. 4 Additional CP eigenstates • Cabbibo favored Decays: My favorite Nicola Cabibbo ferminews-99-10-15

  23. 4 Additional CP eigenstates: PRL:87, 161601(2001)

  24. 4 Additional CP eigenstates: (2) (Preliminary) Angular analysis reveals (Significant longitudinal polarization)

  25. 4 Additional CP eigenstates: (3) Clear B signals

  26. 4 Additional CP eigenstates: (4)

  27. 5 Additional CP eigenstates • Cabibbo suppressed decays: suppressed

  28. 5 Additional CP eigenstates: Preliminary 79fb-1 (85M ) #total=64 #bgd =11.7

  29. 5 Additional CP eigenstates: (2) Preliminary 60fb-1 (65M )

  30. 6 Branching Fractions of Exclusive decays • B+B0 modePDG(2000)* Belle PDG(2000)* Belle * : before Belle and BaBar #: preliminary

  31. 7 Summary (1) • 1)KEKB-Belle operating well (90fb-1 up to now) opening a new frontier • 2)Missing charmonium state: (Consistent with theoretical expectations) • 3) Factorization-forbidden processes found

  32. 7 Summary (2) • 4) Additional CP eigenstates: • 5) Additional CP eigenstates: • 6) Branching Fractions of Exculsive decays • 7) Much more will come soon

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