First Observation and Dalitz Analysis of the ${D}^{0}\ensuremath{\rightarrow}{K}_{S}^{0}\ensuremath{\eta}{\ensuremath{\pi}}^{0}$ Decay

First Observation and Dalitz Analysis of the $D^{0} \to K_{S}^{0} η π^{0}$ Decay

P. Rubin et al. (CLEO Collaboration)

Phys. Rev. Lett. 93, 111801 – Published 9 September 2004

Abstract

Using $9.0 {f b}^{- 1}$ of integrated luminosity in $e^{+} e^{-}$ collisions near the $Υ (4 S)$ mass collected with the CLEO II.V detector we report the first observation of the decay $D^{0} \to K_{S}^{0} η π^{0}$ . We measure the ratio of branching fractions, $\frac{B R (D^{0} \to K_{S}^{0} η π^{0})}{B R (D^{0} \to K_{S}^{0} π^{0})} = 0.46 \pm 0.07 \pm 0.06$ . We perform a Dalitz analysis of 155 selected $D^{0} \to K_{S}^{0} η π^{0}$ candidates and find leading contributions from $a_{0} (980) K_{S}^{0}$ and $K^{*} (892) η$ intermediate states.