\$BK\eta,K\eta^\prime\$ Decays
(01.10.2008)Zusammenfassung
The nonet symmetry scheme seems to describe rather well the masses and
\$\eta-\eta^\prime\$ mixing angle of the ground state pseudo-scalar mesons and
is thus expected to be also a good approximation for the matrix elements of the
pseudo-scalar density operators which play an important role in charmless
two-body B decays with \$\eta\$ or \$\eta^\prime\$ in the final state. In this
talk, I would like to report on a recent work on the \$B^-K^-\eta,
K^-\eta^\prime\$ decay using nonet symmetry for the matrix elements of
pseudo-scalar density operators. We find that the branching ratio \$BPP\$,
with an \$\eta\$ meson in the final state agrees well with data, while those with
an \$\eta^\prime\$ meson are underestimated by \$20-30\%\$. This could be
considered as a more or less successful prediction for QCDF, considering the
theoretical uncertainties involved. This could also indicate that an additional
power-suppressed terms could bring the branching ratio close to experiment, as
with the \$BK^*\pi\$ and \$BK^*\eta\$ decay for which the measured
branching ratios are much bigger than the QCDF predictions.