DOI 10.1007/s100529901111
A theoretical reappraisal of branching ratios and CP
asymmetries in the decays
and determination of the CKM parameters
1 Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
2 INFN, Laboratori Nazionali di Frascati, I-00044 Frascati, Italy
Received: 30 December 1998 / Published online: 27 April 1999
Abstract
We present a theoretical reappraisal of the branching ratios
and CP asymmetries for the decays , with
q=d,s, taking into account current theoretical uncertainties in the
description of the inclusive
decay amplitudes from the long-distance contributions, an improved
treatment of the renormalization scale dependence, and other parametric
dependencies. Concentrating on the
partial branching ratios
, integrated over the invariant dilepton mass region
, we
calculate theoretical precision on the charge-conjugate
averaged partial branching ratios
,CP asymmetries in partial decay rates
, and the ratio of the branching ratios
. For the central values of the CKM parameters,
we find
,
,
,
, and
.The dependence of
and
on the CKM parameters is worked out and the resulting
constraints on the unitarity triangle from an eventual measurement of
are illustrated.
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