Study of Charmless Hadronic<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="italic">B</mml:mi></mml:math>Meson Decays to Pseudoscalar-Vector Final States

Abstract

We report results of searches for charmless hadronic $B$ meson decays to pseudoscalar( ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${\ensuremath{\pi}}^{0}$, or ${K}_{S}^{0}$)-vector( $\ensuremath{\rho}$, ${K}^{*}$, or $\ensuremath{\omega}$) final states. By using $9.7\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected with the CLEO detector, we report the first observation of ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\rho}}^{0}$, ${\overline{B}}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\rho}}^{\ensuremath{\mp}}$, and ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\omega}$, which are expected to be dominated by hadronic $b\ensuremath{\rightarrow}u$ transitions. The measured branching fractions are $({10.4}_{\ensuremath{-}3.4}^{+3.3}\ifmmode\pm\else\textpm\fi{}2.1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $({27.6}_{\ensuremath{-}7.4}^{+8.4}\ifmmode\pm\else\textpm\fi{}4.2)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, and $({11.3}_{\ensuremath{-}2.9}^{+3.3}\ifmmode\pm\else\textpm\fi{}1.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, respectively. Branching fraction upper limits are set for all of the other decay modes investigated.