incontri di fisica del b, parma, 19 th january 2006 on behalf of the collaboration m. bona, m....
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Incontri di fisica del b, Parma, 19th January 2006
stransition 2F in search Physics New
and fitsTriangleUnitarity of Status
on behalf of the Collaborationhttp://www.utfit.org
M. Bona, M. Ciuchini, E. Franco, V. Lubicz,G. Martinelli, F. Parodi, M. Pierini, P. Roudeau,
C. Schiavi, L. Silvestrini, A. Stocchi, V. V.
BolognaBolognaVincenzo VagnoniVincenzo Vagnoni
Vincenzo Vagnoni 2Incontri di fisica del b, Parma, 19th January 2006
CKM Physics: not just a triangle...CKM Physics: not just a triangle...
Incontri di fisica del b, Parma, 19th January 2006
1-2/2
1-2/2
u
c
d s b
A 3(1--i) -A2t
d, sbd, s b
Vtd ,Vts
B Oscillations
A 3(i)
A2
1Vtb
c,u
B decays
b
Vub,Vcb
Wolfenstein parametrization
4 parameters: ,A,
b-Physics plays a crucial role in the determination of those parameters
The CKM matrix The CKM matrix
Vincenzo Vagnoni 4Incontri di fisica del b, Parma, 19th January 2006
† † 1V V V V The CKM is unitary
* * * 0ub ud cb cd tb tdV V V V V V
*22
*
1 1(1 ) ~td tb td td
cd cb cb ts
V V V VAB
V V V V
* 22 2
*
11
2ud ub ub
cd cb cb
V V VAC
V V V
*
*atan
(1 )arg td tb
cd cb
V V
V V
*
*atanarg ud ub
cd cb
V V
V V
1
The Unitarity Triangle The Unitarity Triangle
The non-diagonal elements of the matrix products correspond to 6 triangle equations
Incontri di fisica del b, Parma, 19th January 2006
Bayes Theorem
Standard Model +OPE/HQET/Lattice QCD
to gofrom quarks
to hadrons} , mt}M. Bona et al. (UTfit Collaboration)
JHEP07 (2005) hep-ph/0501199
M. Bona et al. (UTfit Collaboration)hep-ph/0509219
M. Bona et al. (UTfit Collaboration)JHEP07 (2005) hep-ph/0501199
M. Bona et al. (UTfit Collaboration)hep-ph/0509219
The UTThe UTfitfit method and the inputs method and the inputs
Vincenzo Vagnoni 6Incontri di fisica del b, Parma, 19th January 2006
StandardStandard UT UTfitfit: inputs: inputs
Vincenzo Vagnoni 7Incontri di fisica del b, Parma, 19th January 2006
Standard constraints in the plane
Vub/Vcb
K sin()
levels @95% CL
md
md/ms
= 0.343 ± 0.028 [0.289, 0.396] @ 95% Prob.
= 0.343 ± 0.028 [0.289, 0.396] @ 95% Prob.
= 0.214 ± 0.047 [0.112, 0.307] @ 95% Prob.
= 0.214 ± 0.047 [0.112, 0.307] @ 95% Prob.
Incontri di fisica del b, Parma, 19th January 2006
First crucial test of the Standard Model
Determination of CP-violating parameters measuring CP-conserving observables: results fitting with sides only vs CP-violating observables
sin 2 = 0.687 ± 0.032 experimental value from charmonium
sin 2 = 0.793 ± 0.033 expectation from side-only results
Vincenzo Vagnoni 9Incontri di fisica del b, Parma, 19th January 2006
Slight inconsistence in the fit due to an increase of VSlight inconsistence in the fit due to an increase of Vubub
Vincenzo Vagnoni 10Incontri di fisica del b, Parma, 19th January 2006
Tree Processes could be used to « discover » NP comparing «direct» (which are NP free) and «indirect» (where NP contributions could show up) measurements of the same quantity.
Predictions
γ = (57.9 ± 7.4)° γ = 65.0 ± 18.0γ = -115.0 ± 18.0
NEW crucial TEST« Partially » DONE
Vincenzo Vagnoni 11Incontri di fisica del b, Parma, 19th January 2006
Including all the constraints…
= 0.343 ± 0.022 [0.300, 0.385] @ 95% Prob.
= 0.343 ± 0.022 [0.300, 0.385] @ 95% Prob.
= 0.215 ± 0.037 [0.141, 0.286] @ 95% Prob.
= 0.215 ± 0.037 [0.141, 0.286] @ 95% Prob.
Vincenzo Vagnoni 12Incontri di fisica del b, Parma, 19th January 2006
pre-B-factoriesanalysis
UT fit with angles onlyUT fit with angles only
Vincenzo Vagnoni 13Incontri di fisica del b, Parma, 19th January 2006
ms > 14.5 ps-1 at 95% CLSensitivity at 18.5 ps-1
SM prediction on SM prediction on mms s from UT fitsfrom UT fits
Despite the “heroic” efforts at LEP, SLD
and CDF Run-I(now also CDF/D0 Run-II), ms is still
unmeasured
p.d.f. for ms in SM UT fitswithout using its current
experimental limit
ms = 22.2 ± 3.1 ps-1
“Compatibility plot” for an
hypotetical future measurement
> 31 ps-1 @ 3 σ > 38 ps-1 @ 5 σ
Vincenzo Vagnoni 14Incontri di fisica del b, Parma, 19th January 2006
Relevance of LQCD for exploiting Relevance of LQCD for exploiting precise precise mmd,sd,s measurements in measurements in
Unitarity Triangle fitsUnitarity Triangle fits
2
22
2
2
)1(
21
s
d
B
B
s
d
m
m
m
m
2
222622
2
02
2
2 1ˆ)1(6
ssd BB
W
tBWB
Fd BfA
m
mSmm
Gm
mmd,sd,s enter the UT fits through the constraints enter the UT fits through the constraints
where the long distance hadronic quantities are calculated in the where the long distance hadronic quantities are calculated in the framework of LQCD:framework of LQCD:
06.004.024.1ˆ
ˆ
dd
ss
BB
BB
Bf
Bf MeVBf
ss BB 38276ˆ
Vincenzo Vagnoni 15Incontri di fisica del b, Parma, 19th January 2006
Fit with NP-independent constraints
using Tree-level processesassumed to be NP free*the effect of the D0-D0 mixingis negligible wrt the actual error
= ± 0.18 ± 0.11
= ± 0.41 ± 0.05
very important to improve: Vub/Vcb from semileptonic decays
from tree level processes
referencestarting point for NP modelbuilding
Vincenzo Vagnoni 16Incontri di fisica del b, Parma, 19th January 2006
New Physics model independent New Physics model independent parametrization in |parametrization in |F|=2 transitionsF|=2 transitions
sdqBHB
BHBeC
qSMeffq
qfull
effqi
BqB
q,
00
002
The mixing processes being characterized by a single The mixing processes being characterized by a single amplitude, they can be parametrized in a general way by amplitude, they can be parametrized in a general way by means of two parametersmeans of two parameters
HSMeff includes only SM box diagrams while Hfull
eff includes New Physics contributions as well
00
00
Im
Im
KHK
KHKC
SMeff
fulleff
K
For the neutral kaon mixing case, it is convenient to For the neutral kaon mixing case, it is convenient to introduce only one parameterintroduce only one parameter
mK is not considered since the long distance effects are not well controlled
Four “independent” observables (C=1, Four “independent” observables (C=1, =0 in SM)=0 in SM) CBd, Bd, CBs, Bs
5 additional parameters 5 additional parameters
Incontri di fisica del b, Parma, 19th January 2006
not yet available
6 available constraints
Allowing for NP in |Allowing for NP in |F|=2 transitions the F|=2 transitions the additional parameters are left free in the fitadditional parameters are left free in the fit
SMKK
BSM
BSM
BSM
SMsBs
SMdBd
K
s
d
d
s
d
C
mCm
mCm
exp
exp
exp
exp
exp
exp
Vincenzo Vagnoni 18Incontri di fisica del b, Parma, 19th January 2006
|Vub/Vcb| md
K
ACP(J/K0) (DK)
|Vub/Vcb| md
K
ACP(J/K0) (DK)
+ cos2 ASL
cos2 ASL
Using the NP model independentapproach in the fit
SM-like solution
The inclusion of ASL has an impact for suppressing the satellite NP
solution
(very suppressed) « NP » solution
Vincenzo Vagnoni 19Incontri di fisica del b, Parma, 19th January 2006
CBd = 1.27 ± 0.44
Bd = -4.7 ± 2.3
CK = 0.95 ± 0.18
Still 50% room for New Physics in md amplitude
But the New Physics mixing phase is already
very constrained,must be close to zero!
Using the NP model independentapproach in the fit (II)
Vincenzo Vagnoni 20Incontri di fisica del b, Parma, 19th January 2006
New Physics in the bd sector starts to be quite constrained andmost probably will not come as an alternative to
the CKM picture, but rather as a «correction»
What to say/hope then?What to say/hope then?
Basically two scenarios
Minimal Flavour Violation:the only source of flavour
violation is in the SM Yukawa couplings (implies =0)
New Physics couplings between third and second families
(bs sector) are stronger with respect to the bd ones
Flavour physics needs to improve existing measurements in the Bd sector and perform precise measurement in the Bs sector:
Physics case for SuperB and LHCbPhysics case for SuperB and LHCb
Vincenzo Vagnoni 21Incontri di fisica del b, Parma, 19th January 2006
Universal Unitarity Triangle:generalized SM analysis and MFV
MFV = no additional flavour mixingonly mixing processes are sensitive to NP
For UUT we do not use K and md in the fit
= 0.258 ± 0.066 from UUT fit = 0.258 ± 0.066 from UUT fit
= 0.319 ± 0.039 from UUT fit= 0.319 ± 0.039 from UUT fit
Buras et al. hep-ph/0007085
Vincenzo Vagnoni 22Incontri di fisica del b, Parma, 19th January 2006
NP bounds in MFV scenario with small tan
NP enters as additional contributionto the top box diagram(D'Ambrosio et al. hep-ph/0207036)
0 = 2.4 TeV0 is the equivalent SM scale
> 3.6 TeV @ 95% for S0(xt) > 0 > 5.1 TeV @ 95% for S0(xt) < 0
S0 = -0.03 ± 0.54 [-0.90, 1.79] @95% Prob.
S0 = -0.03 ± 0.54 [-0.90, 1.79] @95% Prob.
a = 1 (as a reference)
Vincenzo Vagnoni 23Incontri di fisica del b, Parma, 19th January 2006
S0B ≠ S0
K S0B ≠ S0
K
> 2.6 TeV @ 95% for S0(xt) > 0 > 4.9 TeV @ 95% for S0(xt) < 0
> 3.2 TeV @ 95% for S0(xt) > 0 > 4.9 TeV @ 95% for S0(xt) < 0
S0B S0
K
NP bounds in MFV scenario with large tan
Vincenzo Vagnoni 24Incontri di fisica del b, Parma, 19th January 2006
2010: where will we stand?2010: where will we stand?
ObservableObservable Sensitivity in 2010Sensitivity in 2010
sin2sin2 0.0100.010
55oo
55oo
|V|Vcbcb|| 1%1%
|V|Vubub|| 4%4%
BBKK5%5%
5%5%
3%3%
mmss0.3 ps0.3 ps-1-1 (syst.) (syst.)
sin2sin2 0.0450.045
ss BB B̂f
Assumptions B Factories will collect L=2 ab-1
two good years of data taking at LHCb (L=4 fb-1) improvements in LQCD quantities
Vincenzo Vagnoni 25Incontri di fisica del b, Parma, 19th January 2006
2010 sensitivity to New Physics observables 2010 sensitivity to New Physics observables in |in |F|=2 transitions from UT fitsF|=2 transitions from UT fits
(assuming Standard Model validity)(assuming Standard Model validity)
0.1(now ~0.2)
K0 sector
1.3°
(now ~3°)
Bd sector
0.14(now ~0.5)
1.3o
Bs sector
0.12
Only using the measurements from a few key LHCb BOnly using the measurements from a few key LHCb Bss
channels channels (in particular (in particular mmss and sin2 and sin2)), the precision on NP , the precision on NP
observables for bobservables for bs FCNC transitions in 2010 will be at the s FCNC transitions in 2010 will be at the same level as the bsame level as the bd transitions!d transitions!
Vincenzo Vagnoni 26Incontri di fisica del b, Parma, 19th January 2006
Concluding remarksConcluding remarks A large set of new bounds from B-factories allows over-constraining the
Unitarity Triangle Standard Model is “sadly” showing an impressive consistency in the CKM sector If NP will show up, it will appear as a correction to the SM rather than as a revolution The only tension in the fit comes from a slight disagreement between sin2 and Vub
By using only the constraints from |Vub|/|Vcb| and , we have a (“NP free”) tree level determination of and
This is a starting reference point for NP model building, since all the NP models have to agree with it
Adopting a NP model independent parametrization, we fit SM ( and ) and NP (corrections to SM in mixing amplitudes and phases) together
Constributions of NP to the Bd mixing phase are already very constrained same phase of SM MFV scenarios seem preferred by data
UUT fits are then the starting point of a MFV analysis We can translate the measurement of MFV NP sensitive quantities (mixing) into
bounds on the tested scale
More data are needed for NP hunting at low energies!More data are needed for NP hunting at low energies!