at Belle

1
at Belle
Exclusive and Inclusive Analysis Results

• Katsumi Senyo
• Nagoya University
• May 1618, 2002
• Flavor Physics and CP Violation

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Introduction
Flavor Changing Neutral Current (FCNC) process is
sensitive to new physics (SUSY, charged
Higgs). Very rare decays(BF10-6(exclusive),10-5(
inclusive)). Exclusive mode experimentally easy
to analyze. Inclusive mode theoretically easy
to extract parameters.
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Effective Hamiltonian Approach

• Standard Model are calculated
  to NNLO
• 
  Ali-Lunghi-Greub-Hiller,
  hep-ph/0112300

Beyond SM is expressed as corrections to
SM

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Exclusive mode analysis results
29fb-1 data
PRL88 021801(2002)
A.Ishikawa, Ph.D Thesis, Nagoya Univ. (2002)
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Inclusive Analysis in General
Two kinematical variables to identify B mesons
Signals are identified by fitting Beam energy
constraint mass (Mbc) through this talk.
Beam constraint mass
Energy difference
qq continuum/charmonium background suppression
Thrust angle, B flight direction, Energy
difference (DE), veto mass region
Double b-gtclv-gtslv, c-gtslv decay background
suppression
Lepton ID, Fisher Discriminant (Missing Mass,
Total Energy )
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Reconstruction efficiency
Inclusive 4 Exclusive 10
43fb-1 data used in this inclusive analysis.
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Based on the NNLO calculation. Ali-Lunghi-Greub-H
iller, hep-ph/0112300
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J/y Suppression
For inclusive modes
For exclusive modes
Rejected
Charmonium contaminations after veto
Tight charmonia veto
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Muon ID fake rate 12 with 8085 efficiency
Background Estimation x
mis-ID(fake) rate measured w/ data
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Inclusive mode analysis results
Preliminary
First Evidence!
First Evidence!
Preliminary
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M(Xs) slices of Mbc Distribution
XSee-
XSmm-
K mass region
K mass region
M(Xs)gt1.0GeV/c2 region
Inclusive mode analysis is consistent with the
exclusive mode analysis in M(K), M(K), and the
higher mass region.
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K
K
J/psi and psi vetoes
With higher statistics, more information will be
obtained from M(Xs) and M(ll) distributions.
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Systematic uncertainties
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Exclusive Inclusive Summary
Exclusive mode
Inclusive mode
Preliminary
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Review of Measurements
Experimental results agree with SM theoretical
predictions. In several years experimental
results will significantly improve the constraint
on theoretical prediction well.
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Conclusion

• Establish the existence of the decay
• First evidence on inclusive
• Both consistent with SM predictions
• Promising probe for Beyond SM physics at
  B-factories in next several years

stay tuned and we will be back soon.
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Belle/KEKB Data Accumulation
http//belle.kek.jp/
This talk presents
TODAY(May 18)
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M(Xs) Distribution
With the higher statistics, more information will
be obtained from M(Xs) distribution.
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M(ll) Distribution
With the higher statistics, more information will
be obtained from M(Xs) distribution.
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DE distribution and fit results
DE distribution fit for cross check.
Signal yields are consistent with the Mbc fit
results.