The results of the global CKM analysis include: Wolfenstein parameters, UT angles,
(combinations of) CKM elements, theory parameters and rare
branching fractions.
Detailed background information on the methodology and
the treatment of experimental and theoretical uncertainties
is provided in hep-ph/0406184.
The current combined α constraint shows a peculiar feature
which has an impact on the global CKM fit, the New Physics fit
and predictions of observables like βs:
The global CKM fit shows two preferred solutions (in (ρ-bar,η-bar))
which is caused by the current combined constraint on α
from B→ππ, B→ρρ, and from B→ρπ.
Constraints from "Tree" quantities in the (ρ-bar,η-bar) plane
(γ(DK) and α from the isospin analysis with the help of sin2β (charmonium),
which gives another tree only γ measurement (the only assumption is that the
ΔI=3/2 b-->d EW penguin amplitude is negligible)).
Constraint on α/Φ2 from B→ρπ (U and I only).
The global constraint on α from B→ρπ is a combination
of the most recent BABAR and Belle data. This combination is not
just a naive average in α but a combination in the 26
experimentally measured U and I coefficients which are correlated
among each others. The correlation matrices are provided by both
experiments, BABAR and Belle. The combined constraint has a preferred
region around 120 degrees, and two suppressed regions around
30 and 85 degrees.
Constraints on α/Φ2 from B→ππ (WA), ρπ(WA, Dalitz), ρρ(WA),
compared to the prediction from the CKM fit (not including these measurements).
The combined constraint on α from B→ρπ does not
perfectly fit with the constraints on α from B→ππ
and B→ρρ obtained from the isospin analysis.
The 120 degree solution does not fit perfectly well with B→ρρ
and falls in between two B→ππ solutions.
On the other hand, the 85 degree solution is in good agreement with
both, B→ππ and B→ρρ. As a consequence, one
obtains two preferred regions for α:
around 88 degrees and around 115 degrees.
Constraints on γ/Φ3 from world average D(*)K decays
(GLW+ADS) and Dalitz analyses compared to the prediction from the global
CKM fit (not including these measurements).
New physics (NP) in B0q-B0qbar Mixing
(q = d, s) can be described model-independently by introducing two new parameters
measuring the relative strength (rq2) and the relative phase
(2*Θq) between the B0- B0bar mixing
matrix element containing contributions from the Standard Model (SM) as well as
from NP contributions (full) compared to SM contributions only:
Constraints from |Vud|, |Vus|, |Vcb|,
|Vub|,
Δmd=ΔmdSM * rd2
and sin(2β+2Θd) in the
(rd2,2*Θd) plane.
The inputs have been taken from CKM2006. The corresponding constraint in
the (ρ-bar,η-bar) is just given by the circle obtained from the
inputs |Vud|, |Vus|, |Vcb|, |Vub|
alone since there are four free parameters in the fit
(ρ-bar,η-bar,rd2,2*Θd) but
only three constraints (|Vub|, sin(2β+2Θd),
Δmd=ΔmdSM * rd2)
depend on those. As a consequence, the allowed region in the
(rd2,2*Θd) plane is rather large.
When using in addition the following inputs:
cos(2β) > 0 (suggested by data), α (ππ, 3π, ρρ),
and γ, the allowed regions are substantially reduced in the
(rd2,2*Θd) plane.
There are two allowed regions left. One region is close to the SM
expectation (rd2=1,2*Θd=0) and
another one clearly differing from the SM solution.
Both regions show a doublepeak substructure. This structure is caused
by the current α input which has two preferred regions in alpha.
The non-SM-like region can be suppressed by ASLd,
the dilepton CP asymmetry, in the Bd sector. The inclusive
dilepton asymmetry ASL measured by D0 which is a mixture
of ASLd and ASLs can be
used as well. When combining both inputs one has to allow also for NP
in the Bs sector. Hence, a combined analysis for the
Bd and Bs sector is performed.
The additional inputs used are then ASLd,
ASL, ASLs measured by D0 (which has
currently a quite large uncertainty),
Δms=ΔmsSM*rs2,
and ΔΓsCP' = ΔΓsSM*cos2(2*Θs)
(measured by D0).
The result in the (rd2,2*Θd)
plane shows that the non-SM solution is significantly suppressed.
Also the relative Confidence Level between the two peaks inside the
SM-like region changes as the dilepton asymmetries prefer a negative
sign.
The constraint in the
(rs2,2*Θs) plane shows a strong
constraint on rs2 due to the Δms
measurement from CDF.
Since the central value of ΔΓsCP'
is larger than the ΔΓsSM prediction
regions around 2*Θs=+-π/2 are currently disfavoured.
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