DOI 10.1007/s100520000409
Constraints on the CKM angle
and strong phases from
decays
1 Technische Universität München,
Physik Department, 85748 Garching, Germany
2 Deutsches Elektronen-Synchrotron DESY,
Notkestr. 85, 22607 Hamburg, Germany
Received: 31 March 2000 / Published online: 18 May 2000 - © Springer-Verlag 2000
Abstract
As we pointed out recently, the neutral decays
and
may provide non-trivial bounds on the CKM angle
.
In this paper, we reconsider this approach in the light of recent CLEO data,
which look very interesting. In particular, the results for the corresponding
CP-averaged branching ratios are in favour of strong constraints on
,
where the second quadrant is preferred. Such a situation would be in conflict
with the standard analysis of the unitarity triangle. Moreover, constraints
on a CP-conserving strong phase
are in favour of a negative
value of
,
which would be in conflict with the
factorization expectation. In addition, there seems to be an interesting
discrepancy with the bounds that are implied by the charged
system: whereas these decays favour a range for
that is similar
to that of the neutral modes, they point towards a positive value of
,
which would be in conflict with the expectation of
equal signs for
and
.
If future
data should confirm this ``puzzle'', it may be an indication for new-physics
contributions to the electroweak penguin sector, or a manifestation of
large non-factorizable SU(3)-breaking effects.
Copyright Società Italiana di Fisica, Springer-Verlag 2000