28,552 research outputs found
Implications from recent measurements on sin 2\beta and muon g-2
The recent data on CP asymmetry in and muon g-2 are discussed
in the framework of standard model and beyond. Possible new phase effects
besides the CKM phase are discussed in the processes concerning CP violation in
B decays and muon anomalous magnetic moment (muon g-2). It is found that the
new phases will result in difference between angles measured from
and the one from global fit. The ration between them serves as
a probe of not only new physics but also new phase besides the CKM phase In the
case of muon g-2, the new phase may change the interferences between various
contributions. By including the new phases, some cancelations in the real
coupling cases can be avoided and the large value of muon g-2 observed in the
recent measurements can be understood.Comment: 7 pages, no figure. Talk delivered by Y.F.Zhou at International
Conference on Flavor Physics (ICFP2001), May 31-June.6, at Zhang-Jia-Jie,
Chin
Isospin relation and SU(3) breaking effects of strong phases in Charmless B decays
Isospin and flavor SU(3) relations in charmless hadronic B decays are investigated in detail with paying attention to the SU(3)
symmetry breaking effects in both amplitudes and strong phases. In general, the
isospin and the flavor SU(3) structure of the effective Hamiltonian provide
several relations among the amplitudes and strong phases. Whereas a global fit
to the latest data shows that some relation seems not to be favorable for a
consistent explanation to the current data within the standard model (SM). By
considering several patterns of SU(3) breaking, the amplitudes and the
corresponding strong phases are extracted and compared with the theoretical
estimations. It is found that in the case of SU(3) limits and also the case
with SU(3) breaking only in amplitudes, the fitting results lead to an
unexpected large ratio between two isospin amplitudes
, which is about an order of magnitude larger than the
SM prediction. The results are found to be insensitive to the weak phase
. By including SU(3) breaking effects on the strong phases, one is able
to obtain a consistent fit to the current data within the SM, which implies
that the SU(3) breaking effect on strong phases may play an important role in
understanding the observed charmless hadronic B decay modes and
. It is possible to test those breaking effects in the near future from
more precise measurements of direct CP violation in B factories.Comment: 14 pages, revtex4, no figure, references added. Updated to the latest
data. To appear in Euro. Phys. Journ.
Implications of Charmless B Decays with Large Direct CP Violation
Based on the most recent data in charmless B decays including the very
recently reported large direct CP violations, it is shown that the weak phase
gamma can well be extracted without two-fold ambiguity even only from two decay
modes pi^+pi^- and pi^+K^-, and its value is remarkably consistent with the
global standard model fit at a compatible accuracy. A fit to all the pi pi, pi
K data favor both large electroweak penguin and color-suppressed tree amplitude
with large strong phases. It is demonstrated that the inclusion of small
SU(3)symmetry breaking effects of strong phases and the inelastic rescattering
effects can well improve the consistency of the data, while both effects may
not be sufficient to arrive at a small electroweak penguin amplitude in the
standard model. It is of interest to notice that large or small electroweak
penguin amplitude becomes a testable prediction as they lead to significantly
different predictions for the direct CP violations for pi^0 pi^0, pi^0 K^0
modes. Clearly, precise measurements on charmless B decays will provide a
window for probing new physics.Comment: 4 pages, 1 figure, 1 table, results updated with the latest data.
conclusions unchanged. Refence added. published versio
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