Search for B --> K* nu anti-nu decays

Abstract

We present a search for the decays $B\to K^{\ast }\nu \bar{\nu }$ using 454$\times 10^6$ $B\bar{B}$ pairs collected at the ${\rm Y}(4S)$ resonance with the $mbox{\slshape B\kern-0.1em{\smaller A}\kern-0.1em B\kern-0.1em{\smaller A\kern-0.2em R}}$ detector at the SLAC PEP-II $B$-Factory. We first select an event sample where one $B$ is reconstructed in a semileptonic or hadronic mode with one charmed meson. The remaining particles in the event are then examined to search for a $B\to K^{\ast }\nu \bar{\nu }$ decay. The charged $K^{\ast }$ is reconstructed as $K^{\ast +}\to K_S^0{\pi }^{+}$ or $K^{\ast +}\to K^{+}{\pi }^0$; the neutral $K^{\ast }$ is identified in the $K^{\ast 0}\to K^{+}{\pi }^{-}$ mode. We establish upper limits at 90% confidence level of $\matchal{B}(B^{+} \to K^{*+} ν\barν) < 8 \times 10^{-5}$, $\matchal{B}(B^{0} \to K^{*0} ν\barν) < 12 \times 10^{-5}$, and $\matchal{B}(B \to K^{*} ν\barν) < 8 \times 10^{-5}$.

10 pages, 10 postscript figures