Diapositive 1

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Introduction to Heavy Flavour Physics (..more on
CKM and CP violation)
Achille Stocchi (LAL Orsay/IN2P3-CNRS Université
Paris-Sud)
in 25 minutes
Short introduction. Main motivations
Selection of new measurements
The present situation.
How and why.. to go on
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Short Introduction. Main Motivations
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Flavour Physics in the Standard Model (SM) in the
quark sector
10 free parameters
half of the Standard Model
6 quarks masses
4 CKM parameters
Wolfenstein parametrization l ,A, r, h h
responsible of CP violation in SM
In the Standard Model, charged weak interactions
among quarks are codified in a 3 X 3 unitarity
matrix the CKM Matrix.
The existence of this matrix conveys the fact
that the quarks which participate to weak
processes are a linear combination of mass
eigenstates
The fermion sector is poorly constrained by SM
Higgs Mechanism
mass hierarchy and CKM parameters
4
The Unitarity Triangle
radiative decays Xsg,Xdg, Xsll
B? pp, rp, rr...
theo. clean
B? DK
?
other charmonium
Charm Physics (Dalitz)
from Penguins
5
How measurements constraint UT parameters
g
a
the angles..
sin(2b)
Dms
Dmd
Vub/Vcb
the sides...
CP asymmetries in charmless
B?tn
B?K(r)g

Rare decays... sensitive to NP
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From Childhood
In 2000 the first fundamental test of agreement
between direct and indirect sin2b
To precision era
WE HAVE TO GO ON
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Before starting
We observe hadrons and not
quarks ! theory gives us the link
from quarks to hadrons OPE /HQET/Lattice QCD
. Need to be tested !
To access the parameters of the Standard
Model we need to control the effects induced by
strong interactions
Many measurements ( with different weights ) are
essential
Decay properties and production characteristics
Lifetimes
beauty and charm physics are equally important
Branching ratios
Form factors
Masses (spectroscopy)
Kinematic distributions
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Selection of new measurements()
() some (partial) selection of important
measurements which will be discussed at
this conference. Touch and go. A sort of fil
rouge There are many others, apologies for
not treating them.
I put some results on the backup material
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Angles are accessible through CP violating
measurements
g
a,b
Analogy Double-Slit Experiments with Matter
and Antimatter
source
In the B experiment, we must choose final states
that both a B0 and a B0 can decay into. We
perform the B experiment twice (starting from B0
and from B0). We then compare the results.
In the double-slit experiment, there are two
paths to the same point on the screen.
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The precision on sin2b is still improving..
direct
indirect
b
c
only one amplitude
J/y
c
B0d
s
K0
d
d
theoretically clean at 0.01 To improved with
data!
Dt(ps)
Dt(ps)
sin2b gives the best constraint on r-h plane
sin(2b)
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sin2b from s Penguinsa lot of progress..

g


s
b
s
b
New Physics contribution (2-3 families)
Disagreement between sin2b from b?ccs and
b?qqs still there and intriguing..
CP violation observed in hKs
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Some discrepencies observed between Vub and sin2b
sin2b0.6750.026 From direct measurement
We should keep an eyes on these kinds of
disagreements. Could be NP
sin2b 0.764 0.039 from indirect
determination (all included by sin2b)
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B? p l n
Progress on Vub..
B? Xu l n
Exclusive we start to have quite
precise analysis of Br vs q2
Inclusive improving analyses and improving the
control of the theory vs cuts
Br Vub2 in a limited space phase region
untagged analysis is the most precise
Using Babar El, (Xsg)
Important that we measure at high q2 where
Lattice QCD calculates better.
El
Confirming disagreement
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2
Dms
Dmd
B
f
D
A Milestone the meaurement of the Bs
oscillations after a long saga..
m
B
B
2
2
2
d
h
r
l

-
µ
)
)
1
((
d
d
D
2
m
B
f
s
B
B
s
s
1/x2
CDF only signal at 5s
-0.21
Strong impact on NP on Bs sector. See
later Limiting factor precision on the hadronic
parameter x
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A second milestone the measurement of the
leptonic decay B?tn First leptonic decay seen on
B meson
SM expectation
BR(B ? t ?) (0.85 0.13)10-4
Exp. likelkihood BABARBELLE BR(B ? t ?) (1.31
0.48)10-4
fB 237 37 GeV from expUTfitfB 189 27
GeV Lattice QCD
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Use D0 from D to tag the flavour of D0
D ? D0 p
Mixing in D0 -D0 system Observed !!
BaBar
Submitted to PRL (hep-ex/0703020)
DCS decays
Interference
Oscillations
(1 cosDm t) x2/2 idem for DG y2/2
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Belle
CP eingenstate lifetimes
Method using Dalitz ex D0? K0S p - p
RS and WS occupy the same Dalitz plot
Measurement of strong phase d
Constraint on x,y2 ( also sensitive
to sign of x)
K-K (or p -p ) pure CP D10 K - p
50 D10 D20
Constraint on y
Compare assuming d0 (x'x, y'y)
Best fit
Belle life. (1s)
2.4s
Belle Dalitz
ALL is very exciting. D mixing is Now observed,
we need more Measurements with different
techniques to get x and y parameters.
Within 2s, less if ??0
Two talks tomorrow theory talk.
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Testing lattice QCD on charm sector form factors

Semileptonic D decays. example D?K l n
D
fDs, FD from CLEO-C
Precise measurement, test of the QCD calculation
on charm sector ? Could
be used on B sector x, Vub..
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The present situation
How and Why.. to go on
Ill discuss the present knowledge of the CKM
matrix and CP violation in the SM and beyond and
at the same time try to see what do we need (
theory and next facilities) to effectively look
for NP
Ill use some simulation done for a possible
SuperB facility with 75ab-1
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SM Fit
Global Fit
Dmd,Dms,Vub,Vcb,ek cos2b b a g 2bg
h 0.344 0.016
r 0.163 0.028
We are beyond the era of  alternatives to the
CKM picture. NP should appear as
corrections to the CKM picture
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The problem of particle physics today is where
is the NP scale L 0.5, 11016 TeV
The quantum stabilization of the Electroweak
Scale suggest that L 1 TeV
LHC will search on this range
What happens if the NP scale is at 2-3..10
TeV naturalness is not at loss yet
Flavour Physics explore also this range
We want to perform flavour measurements such that
- if NP particles are discovered at LHC we
able study the flavour structure of the NP -
we can explore NP scale beyond the LHC reach
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Fit in a NP model independent approach
DF2
Parametrizing NP physics in DF2 processes
No new physics C1 j0
Tree processes
5 new free parameters Cs,js Bs mixing
Cd,jd Bd mixing CeK K mixing
1?3 family
Constraints
2?3 family
Today fit possible with 10
contraints and 7 free parameters (r, h,
Cd,jd ,Cs,js, CeK)
1?2 familiy
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NP700 GeV
Precision will be enough to have 5s discrepancy
with today central values
Similar plots in Bs sector where the impact of
LHCb is crucial
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Example on how precise measurements could allow
to explore NP scale beyond the TeV scale

g
MSSM


New Physics contribution (2-3 families)
s
b
s
b
1 10-1 10-2
In the red regions the d are measured with a
significance gt3s away from zero
1 10
With the today precision we do not have 3s
exclusion for any set of parameters
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Some final considerations
Flavour Physics is now in mature age. Many
measurements have been performed and many new we
will discuss at this conference. Some stringent
test of SM has been done (sin2b, Dms)
It is a very active an lively field with many new
results highlight D0
mixing !!
Our goal is to find NP or to measure the
parameters of NP. Quite a lot
of work has been done
More we need to to.. For it we need
Precise measurements (at 1) Precise theory
(Lattice calcs at 1)
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We need to go on in measuring precisely many
different quantites
ACP(B?Xg) AFB(B?Xll) CPV in CF and DCS D
decays Br(t?mg)
CKM angles a,b,g Br(B?tn) and B?
Dln Vub,Vcb radiative decays Br(B?rg,
Kg) many other measurements
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BACKUP MATERIAL
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An example on how to fit the UT parameters and
fit new physics
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B0 ? D0 h0
Together with J/y Kp , DDK
Help in distinguishing between the two b solution
from sin2b measurement
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Many novelties on the measurement of the angle a
Not only Tree diagrams contribute to final
states but also Penguins. Isospin analysis
necessary to extract a
pp modes
rr modes
Important measurement because it gives the
contributions of Penguins diagram
consistent with no CP violation aeff90o (0/180)o
New results also on rp (time dep. Dalitz analysis)
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The angle g still quite a lot of work to do
Most precise measurement come from Dalitz
analysis with D0?Kspp
critical the value of rb
Babar more precise than Belle on x,y but found a
smaller rB larger error on g
New D0 decay explored
BaBar
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Precision measurements of Vcb
Essential point is to control /measure the
effects of strong interaction
Inclusive Vcb still progress
Same for exclusive..
B?Dln
(Babar)
Events/0.5
here we extract
limiting factor F(1)
BaBar/CLEO/CDF/DELPHI Kinetic scheme
Study on charm sector help in the understanding
of strong dynamics
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Radiative B decays moving beyond B?Kg
- many measurement on B?sg - measurements of Br
on B?dg - measurement of ACP on exclusive and
inclusive modes
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SM Fit
No disagreement for g et Dms
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t o d a y L H C b
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NP scale at 350 GeV
Due to the actual disagreement betweenVub and
sin2b we see a slight hint of new physics
Re (dd13)LL vs Im (dd13)LL superB if disagreement
disapper.
SM
Re (dd13)LL vs Im (dd13)LL with
present disagreement
NP at high significance !
Constraint from Dmd Constraint
from sin2b cos2b Constraint from sin2b
All constraints
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MSSM

g
With the today precision we do not have 3s
exclusion
New Physics contribution (2-3 families)


s
b
b
s
1 10-1 10-2
1 10-1
In the red regions the d are measured with a
significance gt3s away from zero
1 10
1 10
In this case the main constraints are b?sg
ACP(b?sg)
Today we would have magenta contour
covering all the space