A big success with more than 200 participants

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A big success with more than 200 participants
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AIM OF THE WORKSHOP
Make an overall status of our knowledge of the
CKM parameters at the end of the era of
CLEO, LEP, SLD, TeVatron I (reach consensus
to start from common base)
Try to define priorities for theoretical
developments and future measurements - in a
short timescale (B-Factories/TeVatron II) - in
a longer timescale (bridging today
LHC)
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Structure of the Workshop
Working Group I Vub, Vcb and Lifetimes
Working Group II Vtd, Vts
Working Group III CKM Fits
Lattice Data Group (LDG)
Forum on Averaging (for PDG users)
Talks on Charm and Kaon Physics
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In the Wolfenstein parameterization 4
parameters l ,A, r, h
The CKM Matrix
d
s
b
u
b
1-l2/2
l
A l3(r-ih)
c,u
Vub,Vcb
c
-l
1-l2/2
Al2
B decays
t
A l3(1-r-ih)
-Al2
1
Vtb
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Measurements
Theory
Measurements
UT parameters

• Analysis Methods
• Analysis Systematic

To be continued at B-Factories and TeVatron

• Theoretical assumptions
• Theoretical uncertainties

Possible measurements
Error Meaning (discussion) Statistical Methods
to extract UT parameters
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WORKING GROUP
I
c,u
b
Vub,Vcb
B decays
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Inclusive Determination of Vcb
Vcb
BR sl t b
Average by LEP Working Groups
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Determination of Vcb limited by theoretical
uncertainties ..
The expression of Vcb in the low scale running HQ
masses formalism (as an example)
Vcb 0.0415 ? ( 1 - 0.012 m2p - 0.010 mb
0.006 as 0.007 r
Can these parameters be determined experimentally
?
In Upsilon expansion formalism
Vcb 0.0419 ? ( 1 0.017 l1 - 0.012 mb ? 0.019
pert)
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From CLEO measurements
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Other experiments should perform this analysis .
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Part of theoretical error on Vcb becomes
experimental from the determination of m2p and mb
Value agreed at the end of the Workshop
Vcb(inclusive) ( 40.7 0.7 0.8 ) 10-3
It was 2.0 and of theo. origin !
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Exclusive Determination of Vcb
G(w) contains kinematics factors and is known
(also r1 and r2)
F(w) is the form factor describing the B? D
transition
At zero recoil (w1), as MQ ? F(1) ? 1
Strategy Measure dG/dw and extrapolate to w1
to extract F(1) Vcb
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F(1) Vcb2
Syst. dominated by the knowledge of the D
(for LEP)
r2
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F(1)
3 determinations
At the Workshop agreement on F(1)
0.910.04 (Gauss.)
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Whats next to improve Vcb
Experimental side
More and new moment analyses
B-factories can perform both exclusive and
inclusive analyses
Form factors measurements in B?Dln
Theory side
More work on the theory for the m2p ,mb extraction
Unquenched F(1) calculations
Studies of eventual correlation between inclusive
and excluive determinations
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Combing the inclusive and the exclusive
measurements
Vcb (41.8 1.0 ) 10-3
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Inclusive determination of Vub
Vub
Challenge measurement from LEP
Using several discriminant variables to
distinguish between
the transitions
b ? c b ? u
B ? Xu l n
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Results from all the LEP experiments
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New determination
At the Workshop we agreed on
Vub(inclusive) (4.09 0.46 0.36) 10-3
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Exclusive determination of Vub
B p(r) l n
Babar
Vub (3.68 0.14 0.21 (syst.)
0.55(theo.))10-3
CLEO
- 0.29
Important theoretical uncertainties from
different models
NOW, Lattice QCD calculations start to be precise
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Whats next to improve Vub
Experimental side
B-factories can perform inclusive/end-point/exclus
ive analyses
Correspondence between D?pln and B ? pln
Theory side
More work on the theory for the extraction of
inclusive/end-point analyses
Lattice QCD calculations for exclusive form
factors
Correlations between the different Vub
determinations
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Lifetimes
All lifetimes of weakly decaying B hadrons
have been precisely measured
Very important test of the B decay
dynamics
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Averages from LEP/SLD/Tevatron ( B-Factories)
t(B0d) 1.543 0.015 ps ( 1.0) t(B)
1.658 0.014 ps ( 0.9) t(B0s) 1.464
0.057 ps ( 3.9) t(LB) 1.208 0.051 ps (
4.2)
The hierarchy was correctly predicted !
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Theory News..
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Next improvements
Experiment side
t(B)/ t(B0) from B factories
But more important t(B0s) and t( LB )
from TeVatron . and ?B Bc, ?c
Theory side
Improvements of the Lattice QCD calculations
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WORKING GROUP II
Dmd
Dms
Radiative and Leptonic B decays
Rare K decays
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Present
Future
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Study of the time dependent behaviour
of the Oscillation B0 -B0
TextBook Plot
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Dmd

• LEP/SLD/CDF precisely measured the Dmd frequency
• Dmd 0.498 0.013 ps-1
  LEP/SLD/CDF (2.6 )
• B-factories confirmed the value improving the
  precision by a factor 2
• Dmd 0.496 0.007 ps-1
  LEP/SLD/CDF/B-factories (1.4)

Before B-Factories
The final B-factories precision will be
about 1 ( 0.004 ps-1 )
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Dms
Combination of different limits using the
amplitude methods
Measurement of A at each Dms
Combination using A and sA
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Hint of signal at Dms17.5 ps-1 but
with significance at 1.7s
Expectation in The Standard Model
Dms gt 14.9 ps-1 at 95 CL
Sensitivity at 19.3 ps-1
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Very important achievement. The Dms
information has to be included in the CKM
Fits using the Likelihood Method. ( in the past
this was a source of differences between the
groups performing CKM fits)
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WORKING GROUP
III
CKM Fits
Strategies
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In the Wolfenstein parameterization 4
parameters l ,A, r, h
The CKM Matrix
d
s
b
u
b
1-l2/2
l
A l3(r-ih)
c,u
Vub,Vcb
c
-l
1-l2/2
Al2
B decays
t
A l3(1-r-ih)
-Al2
1
Vtb
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b?u / b?c Vub \ Vub 2 r2 h2
Dmd Vtd2fBd2 BBd f(mt) (1-r)2 h2
Dmd \ Dmd Vtd \ Vtd 2 fBd2 BBd \ fBs2 BBs (1-r)2 h2
eK f(A,h,r,BK..) h(1-r)
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Treatment of the inputs
Ex BK 0.87 0.06 (gaus) 0.13 (theo.)
Rfit
Bayesian
p.d.f. from convolution (sum in
quadrature)
Likelihood obtained summing linearly the two
errors
Likelihood
Delta Likelihood
Delta Likelihood
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Where the difference is coming from ?
eK ( Vcb4 BK)
Results of the Workshop theoretical error
reduced and
origin of the error better defined
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Differences are small and physics conclusions
quantitatively the same
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The difference ( which is by the way small ) on
the CKM quantities coming from the different
methods, is essentially due to the different
treatment of the theoretical errors
Using Likelihoods as obtained from linear sum
of Exp.Theo. errors
Both methods use the same likelihood
Using Likelihoods as obtained from convolution
of Exp. Theo. errors
Differences almost disappears
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Another example with sin2b
(without eK )
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r 0.220 0.040
at 68CL
h 0.315 0.038
r 0.14-0.30
at 95CL
h 0.24-0.39
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Which are the predictions sin2b, g, Dms
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1988
1995
Mainly thanks to measurements done at LEP
after the end of data taking
Winter 2002
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B Physics has been intensively studied during
last 10 years at LEP/SLD/TeVatron and CLEO and
spectacular improvements have been obtained in
the last years
What will happen next ?
Proceedings by Summer Yellow Book
simultaneous publication in other laboratories
(Slac/Tevatron/Cornell..)
Next Workshop, late Spring 2003 in UK ( Lake
District )
We hope with significant improvement from
B-factories
Aim is to have a LHC preparation workshop in year
B LHC -2 But may well be need for a further a
Workshop before.