A search for the decay $B^+ \to K^+ ν\barν$

Aubert, B.; Collaboration, BABAR

A search for the decay $B^+ \to K^+ ν\barν$

Authors

Description

We search for the rare flavor-changing neutral-current decay $B^+ \to K^+ ν\barν$ in a data sample of 82 fb$^{-1}$ collected with the {\sl BABAR} detector at the PEP-II B-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-B decay. Using these two independent samples we obtain a combined limit of ${\mathcal B}(B^+ \to K^+ ν\barν)<5.2 \times 10^{-5}$ at the 90% confidence level. In addition, by selecting for pions rather than kaons, we obtain a limit of ${\mathcal B}(B^+ \to π^+ ν\barν)<1.0 \times 10^{-4}$ using only the hadronic B reconstruction method.
7 pages, 8 postscript figures, submitted to Phys. Rev. Lett