Observation of ${\mathit{B}}^{+}\to {\mathit{\omega }\mathit{K}}^{+}$ and Search for Related $\mathit{B}$ Decays Modes

We have searched for two-body charmless decays of $B$ mesons to purely hadronic exclusive final states including $\omega$ or $\phi$ mesons using data collected with the CLEO II detector. With this sample of $6.6\times {10}^{6}B$ mesons we observe a signal for the $\omega K^{+}$ final state, and measure a branching fraction of $B(B^{+}\to \omega K^{+})=({1.5}_{-0.6\mathrm{}}^{+0.7\mathrm{}}\pm 0.2)\times {10}^{-5\mathrm{}}$. We also observe some evidence for the $\phi K^{*}$ final state, and upper limits are given for 22 other decay modes. These results provide the opportunity for studies of theoretical models and physical parameters.