Observation of the Exclusive Reaction e+e- -> phi eta at sqrt{s}=10.58 GeV

Abstract

We report the observation of $\e^+e^-\to ϕη$ near $\sqrt{s}$ = 10.58 GeV with 6.5 $\sigma$ significance in the $K^{+}{K}^{-}\gamma \gamma$ final state in a data sample of 224 $f{b}^{-1}$ collected by the BaBar experiment at the PEP-II $e^{+}{e}^{-}$ storage rings. We measure the restricted radiation-corrected cross section to be $σ(\e^+e^- \to ϕη) =$$2.1\pm 0.4(\mathrm{stat})\pm 0.1(\mathrm{syst})\mathrm{fb}$ within the range $|\cos {\theta }^{\ast }|<0.8$, where ${\theta }^{\ast }$ is the center-of-mass polar angle of the $\varphi$ meson. The $\varphi$ meson is required to be in the invariant mass range of 1.008 $<m_{\varphi }<$ 1.035 \gevcc. The radiation-corrected cross section in the full $\cos {\theta }^{\ast }$ range is extrapolated to be $2.9\pm 0.5(\mathrm{stat})\pm 0.1(\mathrm{syst})\mathrm{fb}$.

7 pages, 4 postscript figues, submitted to PRD-RC